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<!--Created on: 8/12/2026 11:58:08 PM-->
<!--Modified on: 8/12/2026 11:58:08 PM-->
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    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract" xlink:label="us-gaap_AssetsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsAbstract" xlink:to="us-gaap_AssetsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US">Assets [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsAbstract_lbl" xml:lang="en-US">ASSETS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="us-gaap_AssetsCurrentAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrentAbstract" xlink:to="us-gaap_AssetsCurrentAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US">Assets, Current [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US">CURRENT ASSETS:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US">Prepaid Expense and Other Assets, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_lbl" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrent" xlink:to="us-gaap_AssetsCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US">Assets, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US">Total current assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentNet" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_lbl" xml:lang="en-US">Property, plant &amp; equipment, net</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseRightOfUseAsset" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xml:lang="en-US">Operating Lease, Right-of-Use Asset</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_lbl" xml:lang="en-US">Operating lease right-of-use asset</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAssetsNoncurrent" xlink:to="us-gaap_OtherAssetsNoncurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xml:lang="en-US">Other Assets, Noncurrent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xml:lang="en-US">Other long-term assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US">Assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US">TOTAL ASSETS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US">LIABILITIES AND STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="us-gaap_LiabilitiesCurrentAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_LiabilitiesCurrentAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US">Liabilities, Current [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US">CURRENT LIABILITIES:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xml:lang="en-US">Accounts Payable and Accrued Liabilities, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_lbl" xml:lang="en-US">Accounts payable and accrued liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilitiesCurrent" xlink:label="us-gaap_DerivativeLiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DerivativeLiabilitiesCurrent" xlink:to="us-gaap_DerivativeLiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DerivativeLiabilitiesCurrent_lbl" xml:lang="en-US">Derivative Liability, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DerivativeLiabilitiesCurrent_lbl" xml:lang="en-US">Warrant liability</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseLiabilityCurrent" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xml:lang="en-US">Operating Lease, Liability, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_lbl" xml:lang="en-US">Lease liability, current</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US">Liabilities, Current</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US">Total current liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xml:lang="en-US">Operating Lease, Liability, Noncurrent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_lbl" xml:lang="en-US">Lease liability, net of current portion</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Liabilities" xlink:to="us-gaap_Liabilities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US">Liabilities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Liabilities_lbl" xml:lang="en-US">TOTAL LIABILITIES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="us-gaap_CommitmentsAndContingencies" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommitmentsAndContingencies" xlink:to="us-gaap_CommitmentsAndContingencies_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xml:lang="en-US">Commitments and Contingencies.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES (Note 7)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquityAbstract" xlink:label="us-gaap_TemporaryEquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityAbstract" xlink:to="us-gaap_TemporaryEquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityAbstract_lbl" xml:lang="en-US">Temporary Equity [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityAbstract_lbl" xml:lang="en-US">MEZZANINE EQUITY:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:to="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US">Temporary Equity, Carrying Amount, Attributable to Parent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US">Balance ending Series D preferred stock</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US">Balance beginning Series D preferred stock</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquityCarryingAmountAttributableToParent_lbl" xml:lang="en-US">Series D preferred stock, 111.11 shares authorized, 0.00 and 111.11 issued and outstanding as of June 30, 2026 and December 31, 2025, respectively</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="us-gaap_StockholdersEquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityAbstract" xlink:to="us-gaap_StockholdersEquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockholdersEquityAbstract_lbl" xml:lang="en-US">STOCKHOLDERS' EQUITY:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockValue" xlink:label="us-gaap_PreferredStockValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockValue" xlink:to="us-gaap_PreferredStockValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockValue_lbl" xml:lang="en-US">Preferred Stock, Value, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PreferredStockValue_lbl" xml:lang="en-US">Series E-2 preferred stock, 1,225 shares authorized; 0.00 and 35.60 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockValue" xlink:to="us-gaap_CommonStockValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockValue_lbl" xml:lang="en-US">Common Stock, Value, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CommonStockValue_lbl" xml:lang="en-US">Common stock, $0.00001 par value; 170,000,000 shares authorized; 8,252,108 and 4,240,129 shares issued and outstanding as of June 30, 2026 and December 31, 2025, respectively</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="us-gaap_AdditionalPaidInCapital" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdditionalPaidInCapital" xlink:to="us-gaap_AdditionalPaidInCapital_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xml:lang="en-US">Additional Paid in Capital</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdditionalPaidInCapital_lbl" xml:lang="en-US">Additional paid-in capital</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Accumulated deficit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Accumulated deficit</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquity" xlink:to="us-gaap_StockholdersEquity_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US">Stockholders' Equity Attributable to Parent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US">Balance ending</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US">Balance beginning</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_StockholdersEquity_lbl" xml:lang="en-US">Total stockholders' equity</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US">Liabilities and Equity</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US">TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SeriesE2PreferredStockMember" xlink:label="clrb_SeriesE2PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SeriesE2PreferredStockMember" xlink:to="clrb_SeriesE2PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SeriesE2PreferredStockMember_lbl" xml:lang="en-US">Represents the information pertaining to Series E-2 preferred stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SeriesE2PreferredStockMember_lbl" xml:lang="en-US">Series E-2 Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SeriesE2PreferredStockMember_lbl" xml:lang="en-US">Series E-2 Preferred Stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquitySharesAuthorized" xlink:label="us-gaap_TemporaryEquitySharesAuthorized" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesAuthorized" xlink:to="us-gaap_TemporaryEquitySharesAuthorized_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xml:lang="en-US">Temporary Equity, Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesAuthorized_lbl" xml:lang="en-US">Temporary equity, preferred stock, shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquitySharesIssued" xlink:label="us-gaap_TemporaryEquitySharesIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesIssued" xlink:to="us-gaap_TemporaryEquitySharesIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xml:lang="en-US">Temporary Equity, Shares Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesIssued_lbl" xml:lang="en-US">Temporary equity, preferred stock, shares issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TemporaryEquitySharesOutstanding" xlink:label="us-gaap_TemporaryEquitySharesOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TemporaryEquitySharesOutstanding" xlink:to="us-gaap_TemporaryEquitySharesOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US">Temporary Equity, Shares Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US">Balance ending Series D preferred stock (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US">Balance beginning Series D preferred stock (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_TemporaryEquitySharesOutstanding_lbl" xml:lang="en-US">Temporary equity, preferred stock, shares outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockParOrStatedValuePerShare" xlink:to="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Preferred stock, par value (in dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesAuthorized" xlink:to="us-gaap_PreferredStockSharesAuthorized_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US">Preferred stock, shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="us-gaap_PreferredStockSharesIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesIssued" xlink:to="us-gaap_PreferredStockSharesIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US">Preferred Stock, Shares Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesIssued_lbl" xml:lang="en-US">Preferred stock, share issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="us-gaap_PreferredStockSharesOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesOutstanding" xlink:to="us-gaap_PreferredStockSharesOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US">Preferred Stock, Shares Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US">Preferred stock, share outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockParOrStatedValuePerShare" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Common Stock, Par or Stated Value Per Share</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Common stock, par value (in dollars per share)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare_lbl" xml:lang="en-US">Common stock par value</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesAuthorized" xlink:to="us-gaap_CommonStockSharesAuthorized_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US">Common stock, shares authorized</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued" xlink:label="us-gaap_CommonStockSharesIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesIssued" xlink:to="us-gaap_CommonStockSharesIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US">Common Stock, Shares, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesIssued_lbl" xml:lang="en-US">Common stock, shares issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesOutstanding" xlink:to="us-gaap_CommonStockSharesOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xml:lang="en-US">Common Stock, Shares, Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xml:lang="en-US">Common stock, shares outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementAbstract" xlink:label="us-gaap_IncomeStatementAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeStatementAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeStatementAbstract_lbl" xml:lang="en-US">CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingCostsAndExpensesAbstract" xlink:label="us-gaap_OperatingCostsAndExpensesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingCostsAndExpensesAbstract" xlink:to="us-gaap_OperatingCostsAndExpensesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingCostsAndExpensesAbstract_lbl" xml:lang="en-US">Operating Costs and Expenses [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingCostsAndExpensesAbstract_lbl" xml:lang="en-US">OPERATING EXPENSES:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ResearchAndDevelopmentExpense" xlink:to="us-gaap_ResearchAndDevelopmentExpense_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xml:lang="en-US">Research and Development Expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpense_lbl" xml:lang="en-US">Research and development</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="us-gaap_GeneralAndAdministrativeExpense" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GeneralAndAdministrativeExpense" xlink:to="us-gaap_GeneralAndAdministrativeExpense_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xml:lang="en-US">General and Administrative Expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GeneralAndAdministrativeExpense_lbl" xml:lang="en-US">General and administrative</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses" xlink:label="us-gaap_CostsAndExpenses" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CostsAndExpenses" xlink:to="us-gaap_CostsAndExpenses_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CostsAndExpenses_lbl" xml:lang="en-US">Costs and Expenses</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CostsAndExpenses_lbl" xml:lang="en-US">Total operating expenses</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingIncomeLoss" xlink:to="us-gaap_OperatingIncomeLoss_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xml:lang="en-US">Operating Income (Loss)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_OperatingIncomeLoss_lbl" xml:lang="en-US">LOSS FROM OPERATIONS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NonoperatingIncomeExpenseAbstract" xlink:to="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xml:lang="en-US">Nonoperating Income (Expense) [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NonoperatingIncomeExpenseAbstract_lbl" xml:lang="en-US">OTHER INCOME (EXPENSE):</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:label="us-gaap_FairValueAdjustmentOfWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAdjustmentOfWarrants" xlink:to="us-gaap_FairValueAdjustmentOfWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US">Fair Value Adjustment of Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US">Gain (loss) on valuation of warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueAdjustmentOfWarrants_lbl" xml:lang="en-US">Change in fair value of warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:to="us-gaap_InterestIncomeExpenseNonoperatingNet_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet_lbl" xml:lang="en-US">Interest Income (Expense), Nonoperating, Net</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet_lbl" xml:lang="en-US">Interest income</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="us-gaap_NonoperatingIncomeExpense" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NonoperatingIncomeExpense" xlink:to="us-gaap_NonoperatingIncomeExpense_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xml:lang="en-US">Nonoperating Income (Expense)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NonoperatingIncomeExpense_lbl" xml:lang="en-US">Total other income (expense)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_lbl" xml:lang="en-US">LOSS BEFORE INCOME TAXES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_NetIncomeLoss_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US">Net loss</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US">Segment and consolidated net loss</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US">NET LOSS</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NetIncomeLoss_lbl" xml:lang="en-US">Net loss</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic" xlink:label="us-gaap_EarningsPerShareBasic" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareBasic" xlink:to="us-gaap_EarningsPerShareBasic_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xml:lang="en-US">Earnings Per Share, Basic</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareBasic_lbl" xml:lang="en-US">NET LOSS PER SHARE - BASIC (In dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="us-gaap_EarningsPerShareDiluted" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareDiluted" xlink:to="us-gaap_EarningsPerShareDiluted_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xml:lang="en-US">Earnings Per Share, Diluted</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareDiluted_lbl" xml:lang="en-US">NET LOSS PER SHARE - DILUTED (In dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_lbl" xml:lang="en-US">WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING - BASIC (In shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_lbl" xml:lang="en-US">WEIGHTED-AVERAGE COMMON SHARES OUTSTANDING - DILUTED (In shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="us-gaap_StatementOfStockholdersEquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfStockholdersEquityAbstract_lbl" xml:lang="en-US">CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightAxis_lbl" xml:lang="en-US">Class of Warrant or Right [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_lbl" xml:lang="en-US">Class of Warrant or Right [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_PreFundedWarrantsMember" xlink:label="clrb_PreFundedWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_PreFundedWarrantsMember" xlink:to="clrb_PreFundedWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_PreFundedWarrantsMember_lbl" xml:lang="en-US">Represents the information pertaining to pre-funded warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_PreFundedWarrantsMember_lbl" xml:lang="en-US">Pre-funded warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_StatementEquityComponentsAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xml:lang="en-US">Equity Components [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="us-gaap_EquityComponentDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_EquityComponentDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquityComponentDomain_lbl" xml:lang="en-US">Equity Component [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockMember" xlink:label="us-gaap_PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockMember" xlink:to="us-gaap_PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US">Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockMember_lbl" xml:lang="en-US">Preferred Stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockMember" xlink:to="us-gaap_CommonStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockMember_lbl" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonStockMember_lbl" xml:lang="en-US">Common Stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="us-gaap_AdditionalPaidInCapitalMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdditionalPaidInCapitalMember" xlink:to="us-gaap_AdditionalPaidInCapitalMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xml:lang="en-US">Additional Paid-In Capital [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AdditionalPaidInCapitalMember_lbl" xml:lang="en-US">Additional Paid-In Capital</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember" xlink:label="us-gaap_RetainedEarningsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetainedEarningsMember" xlink:to="us-gaap_RetainedEarningsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US">Retained Earnings [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US">Accumulated Deficit</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeriesDPreferredStockMember" xlink:label="us-gaap_SeriesDPreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SeriesDPreferredStockMember" xlink:to="us-gaap_SeriesDPreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SeriesDPreferredStockMember_lbl" xml:lang="en-US">Series D Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SeriesDPreferredStockMember_lbl" xml:lang="en-US">Series D preferred stock</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SeriesE4PreferredStockMember" xlink:label="clrb_SeriesE4PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SeriesE4PreferredStockMember" xlink:to="clrb_SeriesE4PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SeriesE4PreferredStockMember_lbl" xml:lang="en-US">Represents the information pertaining to Series E-4 preferred stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SeriesE4PreferredStockMember_lbl" xml:lang="en-US">Series E-4 Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SeriesE4PreferredStockMember_lbl" xml:lang="en-US">Series E-4 preferred stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssued" xlink:label="us-gaap_SharesIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharesIssued" xlink:to="us-gaap_SharesIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharesIssued_lbl" xml:lang="en-US">Shares, Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_SharesIssued_lbl" xml:lang="en-US">Balance ending (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_SharesIssued_lbl" xml:lang="en-US">Balance beginning (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:to="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xml:lang="en-US">Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_lbl" xml:lang="en-US">Stock-based compensation</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockIssuedDuringPeriodValueStockAndWarrants" xlink:label="clrb_StockIssuedDuringPeriodValueStockAndWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockIssuedDuringPeriodValueStockAndWarrants" xlink:to="clrb_StockIssuedDuringPeriodValueStockAndWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockIssuedDuringPeriodValueStockAndWarrants_lbl" xml:lang="en-US">Value of new stock and warrants issued during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockIssuedDuringPeriodValueStockAndWarrants_lbl" xml:lang="en-US">Stock Issued During Period, Value, Stock And Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockIssuedDuringPeriodValueStockAndWarrants_lbl" xml:lang="en-US">Issuance of common stock and pre-funded warrants, net of issuance costs</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockIssuedDuringPeriodSharesStockAndWarrants" xlink:label="clrb_StockIssuedDuringPeriodSharesStockAndWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockIssuedDuringPeriodSharesStockAndWarrants" xlink:to="clrb_StockIssuedDuringPeriodSharesStockAndWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockIssuedDuringPeriodSharesStockAndWarrants_lbl" xml:lang="en-US">Number of new stock and warrants issued during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockIssuedDuringPeriodSharesStockAndWarrants_lbl" xml:lang="en-US">Stock Issued During Period, Shares, Stock And Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockIssuedDuringPeriodSharesStockAndWarrants_lbl" xml:lang="en-US">Issuance of common stock and pre-funded warrants, net of issuance costs (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:to="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Stock Issued During Period, Value, Conversion of Convertible Securities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Conversion of preferred stock into common stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:to="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Conversion of preferred shares into common shares (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Conversion of preferred stock into common stock (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ExerciseOfWarrantsIntoPreferredSharesValue" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ExerciseOfWarrantsIntoPreferredSharesValue" xlink:to="clrb_ExerciseOfWarrantsIntoPreferredSharesValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesValue_lbl" xml:lang="en-US">Amount of exercise of warrants into preferred shares.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesValue_lbl" xml:lang="en-US">Exercise of Warrants Into Preferred Shares, Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesValue_lbl" xml:lang="en-US">Exercise of warrants for preferred stock, net of issuance costs (Note 2)</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ExerciseOfWarrantsIntoPreferredSharesShares" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesShares" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ExerciseOfWarrantsIntoPreferredSharesShares" xlink:to="clrb_ExerciseOfWarrantsIntoPreferredSharesShares_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesShares_lbl" xml:lang="en-US">Number of shares issued at exercise of warrants into preferred shares.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesShares_lbl" xml:lang="en-US">Exercise of Warrants Into Preferred Shares, Shares</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesShares_lbl" xml:lang="en-US">Exercise of warrants for preferred stock, net of issuance costs (Note 2) (in shares)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_ExerciseOfWarrantsIntoPreferredSharesShares_lbl" xml:lang="en-US">Exercise of warrants into preferred shares (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="us-gaap_StatementOfCashFlowsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_StatementOfCashFlowsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xml:lang="en-US">CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">CASH FLOWS FROM OPERATING ACTIVITIES:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Adjustments to reconcile net loss to cash used in operating activities:</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_DepreciationAndAmortizationOfAssets" xlink:label="clrb_DepreciationAndAmortizationOfAssets" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_DepreciationAndAmortizationOfAssets" xlink:to="clrb_DepreciationAndAmortizationOfAssets_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_DepreciationAndAmortizationOfAssets_lbl" xml:lang="en-US">Amount expended on depreciation and amortization of assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_DepreciationAndAmortizationOfAssets_lbl" xml:lang="en-US">Depreciation and Amortization of Assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_DepreciationAndAmortizationOfAssets_lbl" xml:lang="en-US">Depreciation and amortization</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensation" xlink:to="us-gaap_ShareBasedCompensation_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Share-based Compensation</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Stock-based compensation expense</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Total stock-based compensation</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset" xlink:label="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset" xlink:to="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset_lbl" xml:lang="en-US">Amount of periodic reduction over lease term of carrying amount of right-of-use asset from operating lease.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset_lbl" xml:lang="en-US">Increase Decrease In Operating Lease Right Of Use Asset</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_IncreaseDecreaseInOperatingLeaseRightOfUseAsset_lbl" xml:lang="en-US">Change in operating lease right-of-use asset</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US">Changes in:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xml:lang="en-US">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_lbl" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOperatingLeaseLiability" xlink:to="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xml:lang="en-US">Increase (Decrease) in Operating Lease Liability</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability_lbl" xml:lang="en-US">Lease liability</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_lbl" xml:lang="en-US">Increase (Decrease) in Accounts Payable and Accrued Liabilities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_lbl" xml:lang="en-US">Accounts payable and accrued liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xml:lang="en-US">Cash flows from operations</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_lbl" xml:lang="en-US">Cash used in operating activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_lbl" xml:lang="en-US">CASH FLOWS FROM INVESTING ACTIVITIES:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_lbl" xml:lang="en-US">Purchases of property, plant &amp; equipment</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_lbl" xml:lang="en-US">Cash used in investing activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_lbl" xml:lang="en-US">CASH FLOWS FROM FINANCING ACTIVITIES:</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ProceedsFromWarrantExercisesNetOfCosts" xlink:label="clrb_ProceedsFromWarrantExercisesNetOfCosts" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ProceedsFromWarrantExercisesNetOfCosts" xlink:to="clrb_ProceedsFromWarrantExercisesNetOfCosts_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ProceedsFromWarrantExercisesNetOfCosts_lbl" xml:lang="en-US">The cash inflow associated with the amount received from holders exercising their stock warrants, net of cost paid.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ProceedsFromWarrantExercisesNetOfCosts_lbl" xml:lang="en-US">Proceeds From Warrant Exercises, Net Of Costs</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ProceedsFromWarrantExercisesNetOfCosts_lbl" xml:lang="en-US">Net proceeds from warrant exercises</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_ProceedsFromWarrantExercisesNetOfCosts_lbl" xml:lang="en-US">Proceeds from exercise of warrants, net of issuance costs (Note 2)</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet" xlink:label="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet" xlink:to="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet_lbl" xml:lang="en-US">The net cash inflow from the additional capital contribution to the entity and rights to purchase common shares at predetermined price after the issuance costs.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet_lbl" xml:lang="en-US">Proceeds From Issuance Of Common Stock And Warrants, Net</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ProceedsFromIssuanceOfCommonStockAndWarrantsNet_lbl" xml:lang="en-US">Proceeds from issuance of common stock and pre-funded warrants, net of issuance costs (Note 2)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_lbl" xml:lang="en-US">Cash provided by financing activities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_lbl" xml:lang="en-US">NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">CASH AND CASH EQUIVALENTS AT END OF PERIOD</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_lbl" xml:lang="en-US">CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SupplementalCashFlowInformationAbstract" xlink:to="us-gaap_SupplementalCashFlowInformationAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xml:lang="en-US">Supplemental Cash Flow Information [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xml:lang="en-US">SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SettlementOfWarrantsToEquity" xlink:label="clrb_SettlementOfWarrantsToEquity" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SettlementOfWarrantsToEquity" xlink:to="clrb_SettlementOfWarrantsToEquity_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SettlementOfWarrantsToEquity_lbl" xml:lang="en-US">Represents the settlement of warrants to equity in non cash disclosure of cash flow information.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SettlementOfWarrantsToEquity_lbl" xml:lang="en-US">Settlement of Warrants to Equity</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SettlementOfWarrantsToEquity_lbl" xml:lang="en-US">Settlement of warrants to equity</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConversionOfStockAmountConverted1" xlink:label="us-gaap_ConversionOfStockAmountConverted1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConversionOfStockAmountConverted1" xlink:to="us-gaap_ConversionOfStockAmountConverted1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConversionOfStockAmountConverted1_lbl" xml:lang="en-US">Conversion of Stock, Amount Converted</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConversionOfStockAmountConverted1_lbl" xml:lang="en-US">Conversion of preferred stock to common stock</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ValueOfWarrantsIssuedToPlacementAgent" xlink:label="clrb_ValueOfWarrantsIssuedToPlacementAgent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ValueOfWarrantsIssuedToPlacementAgent" xlink:to="clrb_ValueOfWarrantsIssuedToPlacementAgent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ValueOfWarrantsIssuedToPlacementAgent_lbl" xml:lang="en-US">Represents the value of warrants issued to placement agent in non cash disclosure of cash flow information.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ValueOfWarrantsIssuedToPlacementAgent_lbl" xml:lang="en-US">Value of warrants issued to placement agent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ValueOfWarrantsIssuedToPlacementAgent_lbl" xml:lang="en-US">Value of warrants issued to placement agent</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability" xlink:to="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xml:lang="en-US">Right-of-Use Asset Obtained in Exchange for Operating Lease Liability</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability_lbl" xml:lang="en-US">Right of use asset obtained in exchange for operating lease liability</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_lbl" xml:lang="en-US">NATURE OF BUSINESS AND ORGANIZATION</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock_lbl" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock_lbl" xml:lang="en-US">NATURE OF BUSINESS AND ORGANIZATION</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityAbstract" xlink:label="us-gaap_EquityAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquityAbstract" xlink:to="us-gaap_EquityAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquityAbstract_lbl" xml:lang="en-US">STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:to="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xml:lang="en-US">Stockholders' Equity Note Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock_lbl" xml:lang="en-US">STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="us-gaap_FairValueDisclosuresAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_FairValueDisclosuresAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueDisclosuresAbstract_lbl" xml:lang="en-US">FAIR VALUE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosuresTextBlock" xlink:label="us-gaap_FairValueDisclosuresTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueDisclosuresTextBlock" xlink:to="us-gaap_FairValueDisclosuresTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xml:lang="en-US">Fair Value Disclosures [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueDisclosuresTextBlock_lbl" xml:lang="en-US">FAIR VALUE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_lbl" xml:lang="en-US">STOCK-BASED COMPENSATION</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:to="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xml:lang="en-US">Disclosure of Compensation Related Costs, Share-based Payments [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_lbl" xml:lang="en-US">STOCK-BASED COMPENSATION</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="us-gaap_IncomeTaxDisclosureAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxDisclosureAbstract" xlink:to="us-gaap_IncomeTaxDisclosureAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxDisclosureAbstract_lbl" xml:lang="en-US">INCOME TAXES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxDisclosureTextBlock" xlink:to="us-gaap_IncomeTaxDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xml:lang="en-US">Income Tax Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock_lbl" xml:lang="en-US">INCOME TAXES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="us-gaap_EarningsPerShareAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareAbstract" xlink:to="us-gaap_EarningsPerShareAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareAbstract_lbl" xml:lang="en-US">NET LOSS PER SHARE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="us-gaap_EarningsPerShareTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareTextBlock" xlink:to="us-gaap_EarningsPerShareTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xml:lang="en-US">Earnings Per Share [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_EarningsPerShareTextBlock_lbl" xml:lang="en-US">NET LOSS PER SHARE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:to="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_lbl" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeasesAbstract" xlink:label="us-gaap_LeasesAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LeasesAbstract" xlink:to="us-gaap_LeasesAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LeasesAbstract_lbl" xml:lang="en-US">LEASES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeasesTextBlock" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeasesTextBlock" xlink:to="us-gaap_LesseeOperatingLeasesTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xml:lang="en-US">Lessee, Operating Leases [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeOperatingLeasesTextBlock_lbl" xml:lang="en-US">LEASES</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingAbstract" xlink:label="us-gaap_SegmentReportingAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingAbstract" xlink:to="us-gaap_SegmentReportingAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentReportingAbstract_lbl" xml:lang="en-US">OPERATING SEGMENT</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingDisclosureTextBlock" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingDisclosureTextBlock" xlink:to="us-gaap_SegmentReportingDisclosureTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xml:lang="en-US">Segment Reporting Disclosure [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock_lbl" xml:lang="en-US">OPERATING SEGMENT</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="us-gaap_SubsequentEventsAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventsAbstract" xlink:to="us-gaap_SubsequentEventsAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventsAbstract_lbl" xml:lang="en-US">SUBSEQUENT EVENTS</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="us-gaap_SubsequentEventsTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsequentEventsTextBlock" xlink:to="us-gaap_SubsequentEventsTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SubsequentEventsTextBlock_lbl" xml:lang="en-US">SUBSEQUENT EVENTS</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_GoingConcernPolicyTextBlock" xlink:label="clrb_GoingConcernPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_GoingConcernPolicyTextBlock" xlink:to="clrb_GoingConcernPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_GoingConcernPolicyTextBlock_lbl" xml:lang="en-US">Disclosure of accounting policy for going concern.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_GoingConcernPolicyTextBlock_lbl" xml:lang="en-US">Going Concern [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_GoingConcernPolicyTextBlock_lbl" xml:lang="en-US">Going Concern</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationPolicyTextBlock" xlink:label="us-gaap_ConsolidationPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConsolidationPolicyTextBlock" xlink:to="us-gaap_ConsolidationPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xml:lang="en-US">Consolidation, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ConsolidationPolicyTextBlock_lbl" xml:lang="en-US">Principles of Consolidation</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UseOfEstimates" xlink:label="us-gaap_UseOfEstimates" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UseOfEstimates" xlink:to="us-gaap_UseOfEstimates_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UseOfEstimates_lbl" xml:lang="en-US">Use of Estimates, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_UseOfEstimates_lbl" xml:lang="en-US">Use of Estimates</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xml:lang="en-US">Cash and Cash Equivalents</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:to="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xml:lang="en-US">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_lbl" xml:lang="en-US">Property, Plant &amp; Equipment</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock" xlink:label="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock" xlink:to="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock_lbl" xml:lang="en-US">Disclosure of accounting policy for right of use assets and lease liability.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock_lbl" xml:lang="en-US">Right Of Use Assets And Lease Liability Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_RightOfUseAssetsAndLeaseLiabilityPolicyPolicyTextBlock_lbl" xml:lang="en-US">Right-of-Use Asset and Lease Liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:to="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xml:lang="en-US">Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy_lbl" xml:lang="en-US">Stock-Based Compensation</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpensePolicy" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ResearchAndDevelopmentExpensePolicy" xlink:to="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xml:lang="en-US">Research and Development Expense, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpensePolicy_lbl" xml:lang="en-US">Research and Development</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="us-gaap_IncomeTaxPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxPolicyTextBlock" xlink:to="us-gaap_IncomeTaxPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xml:lang="en-US">Income Tax, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xml:lang="en-US">Income Taxes</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:to="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xml:lang="en-US">Fair Value of Financial Instruments, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueOfFinancialInstrumentsPolicy_lbl" xml:lang="en-US">Fair Value of Financial Instruments</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativesPolicyTextBlock" xlink:label="us-gaap_DerivativesPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DerivativesPolicyTextBlock" xlink:to="us-gaap_DerivativesPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DerivativesPolicyTextBlock_lbl" xml:lang="en-US">Derivatives, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_DerivativesPolicyTextBlock_lbl" xml:lang="en-US">Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityPolicyTextBlock" xlink:label="us-gaap_StockholdersEquityPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityPolicyTextBlock" xlink:to="us-gaap_StockholdersEquityPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityPolicyTextBlock_lbl" xml:lang="en-US">Stockholders' Equity, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockholdersEquityPolicyTextBlock_lbl" xml:lang="en-US">Preferred Stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskCreditRisk" xlink:label="us-gaap_ConcentrationRiskCreditRisk" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConcentrationRiskCreditRisk" xlink:to="us-gaap_ConcentrationRiskCreditRisk_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xml:lang="en-US">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ConcentrationRiskCreditRisk_lbl" xml:lang="en-US">Concentration of Credit Risk</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistancePolicyTextBlock" xlink:label="us-gaap_GovernmentAssistancePolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistancePolicyTextBlock" xlink:to="us-gaap_GovernmentAssistancePolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistancePolicyTextBlock_lbl" xml:lang="en-US">Government Assistance [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GovernmentAssistancePolicyTextBlock_lbl" xml:lang="en-US">Government Assistance</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US">Recently Issued Accounting Pronouncements Not Yet Adopted</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" xlink:label="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" xlink:to="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_lbl" xml:lang="en-US">Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock_lbl" xml:lang="en-US">Summary of outstanding warrants to purchase common stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_lbl" xml:lang="en-US">Fair Value Measurements, Recurring and Nonrecurring [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_July2024WarrantsMember" xlink:label="clrb_July2024WarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_July2024WarrantsMember" xlink:to="clrb_July2024WarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_July2024WarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to July 2024 warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_July2024WarrantsMember_lbl" xml:lang="en-US">July 2024 Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_July2024WarrantsMember_lbl" xml:lang="en-US">July 2024 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_September2023WarrantsMember" xlink:label="clrb_September2023WarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_September2023WarrantsMember" xlink:to="clrb_September2023WarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_September2023WarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to September 2023 warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_September2023WarrantsMember_lbl" xml:lang="en-US">September 2023 Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_September2023WarrantsMember_lbl" xml:lang="en-US">September 2023 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyTwoCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentyTwoCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyTwoCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentyTwoCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyTwoCommonWarrantsMember_lbl" xml:lang="en-US">This member stands for 2022 common warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyTwoCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Two Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyTwoCommonWarrantsMember_lbl" xml:lang="en-US">2022 Common Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_TwoThousandTwentyTwoCommonWarrantsMember_lbl" xml:lang="en-US">October 2022 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xml:lang="en-US">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_lbl" xml:lang="en-US">FAIR VALUE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock_lbl" xml:lang="en-US">Fair Value, Assets Measured on Recurring Basis [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisTextBlock_lbl" xml:lang="en-US">Schedule of financial instruments measured at fair value on a recurring basis</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xml:lang="en-US">Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock_lbl" xml:lang="en-US">Schedule of modified option pricing assumptions and assumptions used upon issuance</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xml:lang="en-US">Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock_lbl" xml:lang="en-US">Schedule of changes in the fair market value of the warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock" xlink:label="us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock_lbl" xml:lang="en-US">Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTableTextBlock_lbl" xml:lang="en-US">Summary of the expense for stock-based compensation related to stock option grants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_lbl" xml:lang="en-US">Schedule of dilutive securities have been excluded from the computation of diluted net loss per share</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Maturity [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock_lbl" xml:lang="en-US">Schedule of the Company's undiscounted payments for its short-term leases and operating lease liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xlink:to="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xml:lang="en-US">Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock_lbl" xml:lang="en-US">Schedule of financial data for the one reportable segment</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NatureOfBusinessAndOrganizationTable" xlink:label="clrb_NatureOfBusinessAndOrganizationTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NatureOfBusinessAndOrganizationTable" xlink:to="clrb_NatureOfBusinessAndOrganizationTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NatureOfBusinessAndOrganizationTable_lbl" xml:lang="en-US">Disclosure information about Nature of Business and Organization.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NatureOfBusinessAndOrganizationTable_lbl" xml:lang="en-US">Nature of Business and Organization [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="srt_RangeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_RangeAxis" xlink:to="srt_RangeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_RangeAxis_lbl" xml:lang="en-US">Range [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="srt_RangeMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_RangeMember" xlink:to="srt_RangeMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_RangeMember_lbl" xml:lang="en-US">Range [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="srt_MinimumMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_MinimumMember" xlink:to="srt_MinimumMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_MinimumMember_lbl" xml:lang="en-US">Minimum [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="srt_MinimumMember_lbl" xml:lang="en-US">Minimum</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="srt_MaximumMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="srt_MaximumMember" xlink:to="srt_MaximumMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="srt_MaximumMember_lbl" xml:lang="en-US">Maximum [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="srt_MaximumMember_lbl" xml:lang="en-US">Maximum</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:to="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentByTypeAxis_lbl" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:to="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentTypeDomain_lbl" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="us-gaap_LeaseholdImprovementsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LeaseholdImprovementsMember" xlink:to="us-gaap_LeaseholdImprovementsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xml:lang="en-US">Leasehold Improvements [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LeaseholdImprovementsMember_lbl" xml:lang="en-US">Leasehold improvements</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistanceTypeAxis" xlink:label="us-gaap_GovernmentAssistanceTypeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistanceTypeAxis" xlink:to="us-gaap_GovernmentAssistanceTypeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistanceTypeAxis_lbl" xml:lang="en-US">Government Assistance, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistanceTypeDomain" xlink:label="us-gaap_GovernmentAssistanceTypeDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistanceTypeDomain" xlink:to="us-gaap_GovernmentAssistanceTypeDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistanceTypeDomain_lbl" xml:lang="en-US">Government Assistance, Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember" xlink:label="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember" xlink:to="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember_lbl" xml:lang="en-US">Represents the information pertaining to cancer treatment research award through the National Cancer Institute (NCI).</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember_lbl" xml:lang="en-US">Cancer Treatment Research Award Through National Cancer Institute [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_CancerTreatmentResearchAwardThroughNationalCancerInstituteMember_lbl" xml:lang="en-US">Cancer treatment research award through the National Cancer Institute (NCI)</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NatureOfBusinessAndOrganizationLineItem" xlink:label="clrb_NatureOfBusinessAndOrganizationLineItem" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NatureOfBusinessAndOrganizationLineItem_lbl" xml:lang="en-US">Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NatureOfBusinessAndOrganizationLineItem_lbl" xml:lang="en-US">Nature of Business and Organization [ Line Item]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NatureOfBusinessAndOrganizationLineItem_lbl" xml:lang="en-US">NATURE OF BUSINESS AND ORGANIZATION</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_UnrestrictedCashAndCashEquivalents" xlink:label="clrb_UnrestrictedCashAndCashEquivalents" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_UnrestrictedCashAndCashEquivalents" xlink:to="clrb_UnrestrictedCashAndCashEquivalents_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_UnrestrictedCashAndCashEquivalents_lbl" xml:lang="en-US">Carrying amount as of the balance sheet date of cash and cash equivalents with respect to unrestricted balances.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_UnrestrictedCashAndCashEquivalents_lbl" xml:lang="en-US">Unrestricted Cash and Cash Equivalents</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_UnrestrictedCashAndCashEquivalents_lbl" xml:lang="en-US">Unrestricted cash and cash equivalents</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockCapitalReservedForFutureIssuanceUpfront" xlink:label="clrb_StockCapitalReservedForFutureIssuanceUpfront" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockCapitalReservedForFutureIssuanceUpfront" xlink:to="clrb_StockCapitalReservedForFutureIssuanceUpfront_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockCapitalReservedForFutureIssuanceUpfront_lbl" xml:lang="en-US">Aggregate upfront amount of shares reserved for future issuance.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockCapitalReservedForFutureIssuanceUpfront_lbl" xml:lang="en-US">Stock, Capital Reserved for Future Issuance, Upfront</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockCapitalReservedForFutureIssuanceUpfront_lbl" xml:lang="en-US">Additional securities purchase agreement, upfront</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased" xlink:label="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased" xlink:to="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased_lbl" xml:lang="en-US">Maximum milestone based amount of shares reserved for future issuance.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased_lbl" xml:lang="en-US">Stock, Maximum Capital Reserved for Future Issuance, Milestone Based</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockMaximumCapitalReservedForFutureIssuanceMilestoneBased_lbl" xml:lang="en-US">Additional securities purchase agreement, milestone based</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfReportableSegments" xlink:label="us-gaap_NumberOfReportableSegments" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfReportableSegments" xlink:to="us-gaap_NumberOfReportableSegments_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xml:lang="en-US">Number of Reportable Segments</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xml:lang="en-US">Number of reportable segments</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TangibleAssetImpairmentCharges" xlink:label="us-gaap_TangibleAssetImpairmentCharges" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TangibleAssetImpairmentCharges" xlink:to="us-gaap_TangibleAssetImpairmentCharges_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TangibleAssetImpairmentCharges_lbl" xml:lang="en-US">Tangible Asset Impairment Charges</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_TangibleAssetImpairmentCharges_lbl" xml:lang="en-US">Fixed asset impairment charges</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:label="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease" xlink:to="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnrecognizedTaxBenefitsPeriodIncreaseDecrease_lbl" xml:lang="en-US">Unrecognized Tax Benefits, Period Increase (Decrease)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashUninsuredAmount" xlink:label="us-gaap_CashUninsuredAmount" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashUninsuredAmount" xlink:to="us-gaap_CashUninsuredAmount_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashUninsuredAmount_lbl" xml:lang="en-US">Cash, Uninsured Amount</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CashUninsuredAmount_lbl" xml:lang="en-US">Uninsured cash balances</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:to="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xml:lang="en-US">Property, Plant and Equipment, Useful Life</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xml:lang="en-US">Property and equipment useful lives</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistanceAmount" xlink:label="us-gaap_GovernmentAssistanceAmount" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistanceAmount" xlink:to="us-gaap_GovernmentAssistanceAmount_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistanceAmount_lbl" xml:lang="en-US">Government Assistance, Amount</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GovernmentAssistanceAmount_lbl" xml:lang="en-US">Grant received</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistanceStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration" xlink:label="us-gaap_GovernmentAssistanceStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistanceStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration" xlink:to="us-gaap_GovernmentAssistanceStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistanceStatementOfIncomeOrComprehensiveIncomeExtensibleEnumeration_lbl" xml:lang="en-US">Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GovernmentAssistanceTransactionDuration" xlink:label="us-gaap_GovernmentAssistanceTransactionDuration" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GovernmentAssistanceTransactionDuration" xlink:to="us-gaap_GovernmentAssistanceTransactionDuration_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GovernmentAssistanceTransactionDuration_lbl" xml:lang="en-US">Government Assistance, Transaction Duration</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_GovernmentAssistanceTransactionDuration_lbl" xml:lang="en-US">Period over which cancer treatment research award was received.</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ProceedsFromResearchAndDevelopment" xlink:label="clrb_ProceedsFromResearchAndDevelopment" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ProceedsFromResearchAndDevelopment" xlink:to="clrb_ProceedsFromResearchAndDevelopment_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ProceedsFromResearchAndDevelopment_lbl" xml:lang="en-US">Amount of proceeds from research and development.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ProceedsFromResearchAndDevelopment_lbl" xml:lang="en-US">Proceeds From Research And Development</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ProceedsFromResearchAndDevelopment_lbl" xml:lang="en-US">Reduction in research and development</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_lbl" xml:lang="en-US">Share-based compensation expiration period</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="us-gaap_ClassOfWarrantOrRightTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_ClassOfWarrantOrRightTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightTable_lbl" xml:lang="en-US">Class of Warrant or Right [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_CommonStockWarrantMember" xlink:label="clrb_CommonStockWarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_CommonStockWarrantMember" xlink:to="clrb_CommonStockWarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_CommonStockWarrantMember_lbl" xml:lang="en-US">This member stands for common stock warrant.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_CommonStockWarrantMember_lbl" xml:lang="en-US">Common Stock Warrant [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_CommonStockWarrantMember_lbl" xml:lang="en-US">Common warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_PrefundedWarrantMember" xlink:label="clrb_PrefundedWarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_PrefundedWarrantMember" xlink:to="clrb_PrefundedWarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_PrefundedWarrantMember_lbl" xml:lang="en-US">This member stands for Prefunded Warrant.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_PrefundedWarrantMember_lbl" xml:lang="en-US">Prefunded Warrant [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_PrefundedWarrantMember_lbl" xml:lang="en-US">Prefunded Warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ExistingWarrantsMember" xlink:label="clrb_ExistingWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ExistingWarrantsMember" xlink:to="clrb_ExistingWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ExistingWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to warrants issued by the company on June 5, 2020, October 25, 2022 and July 21, 2024, collectively referred as existing warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ExistingWarrantsMember_lbl" xml:lang="en-US">Existing Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ExistingWarrantsMember_lbl" xml:lang="en-US">Existing Warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFiveOctoberWarrantsMember" xlink:label="clrb_TwoThousandTwentyFiveOctoberWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFiveOctoberWarrantsMember" xlink:to="clrb_TwoThousandTwentyFiveOctoberWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFiveOctoberWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to warrants inducement by the company October 2025.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFiveOctoberWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Five October Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFiveOctoberWarrantsMember_lbl" xml:lang="en-US">October 2025 Warrant Inducement</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TrancheWarrantsMember" xlink:label="clrb_TrancheWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TrancheWarrantsMember" xlink:to="clrb_TrancheWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TrancheWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to Tranche A warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TrancheWarrantsMember_lbl" xml:lang="en-US">Tranche A Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TrancheWarrantsMember_lbl" xml:lang="en-US">Tranche A Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2026 May Tranche C Common Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Six May Tranche C Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentySixMayTrancheCCommonWarrantsMember_lbl" xml:lang="en-US">2026 May Tranche C Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember" xlink:label="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember" xlink:to="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember_lbl" xml:lang="en-US">Represents information Pertaining to 2026 May Placement Agent Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Six May Placement Agent Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentySixMayPlacementAgentWarrantsMember_lbl" xml:lang="en-US">2026 May Placement Agent Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember" xlink:label="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember" xlink:to="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember_lbl" xml:lang="en-US">This member stands for 2023 Tranche A Preferred Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Three Tranche A Preferred Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember_lbl" xml:lang="en-US">2023 Tranche A Preferred Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_TwoThousandTwentyThreeTranchePreferredWarrantsMember_lbl" xml:lang="en-US">2023 Tranche A warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember" xlink:label="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember" xlink:to="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember_lbl" xml:lang="en-US">This member stands for 2023 Tranche B Preferred Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Three Tranche B Preferred Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember_lbl" xml:lang="en-US">2023 Tranche B Preferred Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_TwoThousandTwentyThreeTrancheBPreferredWarrantsMember_lbl" xml:lang="en-US">2023 Tranche B warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFourTrancheaWarrantsMember" xlink:label="clrb_TwoThousandTwentyFourTrancheaWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFourTrancheaWarrantsMember" xlink:to="clrb_TwoThousandTwentyFourTrancheaWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFourTrancheaWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2024 Tranche A warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFourTrancheaWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Four Tranche A Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFourTrancheaWarrantsMember_lbl" xml:lang="en-US">2024 Tranche A Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFourTrancheBWarrantsMember" xlink:label="clrb_TwoThousandTwentyFourTrancheBWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFourTrancheBWarrantsMember" xlink:to="clrb_TwoThousandTwentyFourTrancheBWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFourTrancheBWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2024 Tranche B warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFourTrancheBWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Four Tranche B Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFourTrancheBWarrantsMember_lbl" xml:lang="en-US">2024 Tranche B Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFourTrancheCWarrantsMember" xlink:label="clrb_TwoThousandTwentyFourTrancheCWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFourTrancheCWarrantsMember" xlink:to="clrb_TwoThousandTwentyFourTrancheCWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFourTrancheCWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2024 Tranche C warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFourTrancheCWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Four Tranche C Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFourTrancheCWarrantsMember_lbl" xml:lang="en-US">2024 Tranche C Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember" xlink:label="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember" xlink:to="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2025 representative warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Five Representative Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFiveRepresentativeWarrantsMember_lbl" xml:lang="en-US">2025 Representative Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="us-gaap_CommonClassAMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonClassAMember" xlink:to="us-gaap_CommonClassAMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonClassAMember_lbl" xml:lang="en-US">Common Class A [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonClassAMember_lbl" xml:lang="en-US">Class A Units</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="us-gaap_CommonClassBMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonClassBMember" xlink:to="us-gaap_CommonClassBMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonClassBMember_lbl" xml:lang="en-US">Common Class B [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_CommonClassBMember_lbl" xml:lang="en-US">Class B Unit</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SeriesE1PreferredStockMember" xlink:label="clrb_SeriesE1PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SeriesE1PreferredStockMember" xlink:to="clrb_SeriesE1PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SeriesE1PreferredStockMember_lbl" xml:lang="en-US">Represents the information pertaining to Series E-1 preferred stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SeriesE1PreferredStockMember_lbl" xml:lang="en-US">Series E-1 Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SeriesE1PreferredStockMember_lbl" xml:lang="en-US">Series E-1 preferred stock</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SeriesE3PreferredStockMember" xlink:label="clrb_SeriesE3PreferredStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SeriesE3PreferredStockMember" xlink:to="clrb_SeriesE3PreferredStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SeriesE3PreferredStockMember_lbl" xml:lang="en-US">Represents the information pertaining to Series E-3 preferred stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SeriesE3PreferredStockMember_lbl" xml:lang="en-US">Series E-3 Preferred Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SeriesE3PreferredStockMember_lbl" xml:lang="en-US">Series E-3 preferred stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="us-gaap_SubsidiarySaleOfStockAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SubsidiarySaleOfStockAxis" xlink:to="us-gaap_SubsidiarySaleOfStockAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SubsidiarySaleOfStockAxis_lbl" xml:lang="en-US">Sale of Stock [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SaleOfStockNameOfTransactionDomain_lbl" xml:lang="en-US">Sale of Stock [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_PublicOfferingMember" xlink:label="clrb_PublicOfferingMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_PublicOfferingMember" xlink:to="clrb_PublicOfferingMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_PublicOfferingMember_lbl" xml:lang="en-US">Represents information pertaining to public offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_PublicOfferingMember_lbl" xml:lang="en-US">Public Offering [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_PublicOfferingMember_lbl" xml:lang="en-US">Public offering</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_RegisteredDirectOfferingMember" xlink:label="clrb_RegisteredDirectOfferingMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_RegisteredDirectOfferingMember" xlink:to="clrb_RegisteredDirectOfferingMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_RegisteredDirectOfferingMember_lbl" xml:lang="en-US">Represents the member information pertaining to registered direct offering.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_RegisteredDirectOfferingMember_lbl" xml:lang="en-US">Registered Direct Offering [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_RegisteredDirectOfferingMember_lbl" xml:lang="en-US">Registered direct offering</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverAllotmentOptionMember" xlink:label="us-gaap_OverAllotmentOptionMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OverAllotmentOptionMember" xlink:to="us-gaap_OverAllotmentOptionMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OverAllotmentOptionMember_lbl" xml:lang="en-US">Over-Allotment Option [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OverAllotmentOptionMember_lbl" xml:lang="en-US">Over allotment option</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_September2023PrivatePlacementMember" xlink:label="clrb_September2023PrivatePlacementMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_September2023PrivatePlacementMember" xlink:to="clrb_September2023PrivatePlacementMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_September2023PrivatePlacementMember_lbl" xml:lang="en-US">Represents the information pertaining to September 2023 Private Placement.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_September2023PrivatePlacementMember_lbl" xml:lang="en-US">September 2023 Private Placement [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_September2023PrivatePlacementMember_lbl" xml:lang="en-US">September 2023 Private Placement</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrivatePlacementMember" xlink:label="us-gaap_PrivatePlacementMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrivatePlacementMember" xlink:to="us-gaap_PrivatePlacementMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PrivatePlacementMember_lbl" xml:lang="en-US">Private Placement [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PrivatePlacementMember_lbl" xml:lang="en-US">Private placement</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_October2022PublicOfferingAndPrivatePlacementMember" xlink:label="clrb_October2022PublicOfferingAndPrivatePlacementMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_October2022PublicOfferingAndPrivatePlacementMember" xlink:to="clrb_October2022PublicOfferingAndPrivatePlacementMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_October2022PublicOfferingAndPrivatePlacementMember_lbl" xml:lang="en-US">This member stands for October 2022 Public Offering and Private Placement.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_October2022PublicOfferingAndPrivatePlacementMember_lbl" xml:lang="en-US">October 2022 Public Offering and Private Placement[Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_October2022PublicOfferingAndPrivatePlacementMember_lbl" xml:lang="en-US">October 2022 Public Offering and Private Placement</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US">Class of Warrant or Right [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems_lbl" xml:lang="en-US">STOCKHOLDERS' EQUITY</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockCapitalReservedForFutureIssuanceGrossUpfront" xlink:label="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront" xlink:to="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront_lbl" xml:lang="en-US">Aggregate gross upfront amount of shares reserved for future issuance.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront_lbl" xml:lang="en-US">Stock, Capital Reserved for Future Issuance, Gross Upfront</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockCapitalReservedForFutureIssuanceGrossUpfront_lbl" xml:lang="en-US">Additional securities purchase agreement, gross upfront</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_StockCapitalReservedForFutureIssuanceNetUpfront" xlink:label="clrb_StockCapitalReservedForFutureIssuanceNetUpfront" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_StockCapitalReservedForFutureIssuanceNetUpfront" xlink:to="clrb_StockCapitalReservedForFutureIssuanceNetUpfront_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_StockCapitalReservedForFutureIssuanceNetUpfront_lbl" xml:lang="en-US">Aggregate net upfront amount of shares reserved for future issuance.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_StockCapitalReservedForFutureIssuanceNetUpfront_lbl" xml:lang="en-US">Stock, Capital Reserved for Future Issuance, Net Upfront</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_StockCapitalReservedForFutureIssuanceNetUpfront_lbl" xml:lang="en-US">Additional securities purchase agreement, net upfront</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOrSaleOfEquity" xlink:to="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xml:lang="en-US">Proceeds from Issuance or Sale of Equity</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOrSaleOfEquity_lbl" xml:lang="en-US">Gross proceeds from stockholders' equity</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfUnitsIssued" xlink:label="clrb_NumberOfUnitsIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfUnitsIssued" xlink:to="clrb_NumberOfUnitsIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfUnitsIssued_lbl" xml:lang="en-US">Represents the number of units issued.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfUnitsIssued_lbl" xml:lang="en-US">Number Of Units Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfUnitsIssued_lbl" xml:lang="en-US">Number of units issued</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfSharesInUnit" xlink:label="clrb_NumberOfSharesInUnit" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfSharesInUnit" xlink:to="clrb_NumberOfSharesInUnit_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfSharesInUnit_lbl" xml:lang="en-US">Represents number of shares in each unit.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfSharesInUnit_lbl" xml:lang="en-US">Number Of Shares In Unit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfSharesInUnit_lbl" xml:lang="en-US">Number of shares in a unit</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfWarrantsInUnit" xlink:label="clrb_NumberOfWarrantsInUnit" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfWarrantsInUnit" xlink:to="clrb_NumberOfWarrantsInUnit_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfWarrantsInUnit_lbl" xml:lang="en-US">Represents number of warrant in each unit.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfWarrantsInUnit_lbl" xml:lang="en-US">Number Of Warrants In Unit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfWarrantsInUnit_lbl" xml:lang="en-US">Number of warrants in a unit</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Each Warrant or Right</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight_lbl" xml:lang="en-US">Number of shares of common stock per warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_PricePerUnit" xlink:label="clrb_PricePerUnit" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_PricePerUnit" xlink:to="clrb_PricePerUnit_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_PricePerUnit_lbl" xml:lang="en-US">Represents the per unit price of units issued.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_PricePerUnit_lbl" xml:lang="en-US">Price per Unit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_PricePerUnit_lbl" xml:lang="en-US">Price per unit</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold" xlink:to="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold_lbl" xml:lang="en-US">Represents volume weighted average price threshold of the issuer's common stock required to be met before a class of warrants or rights becomes callable.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold_lbl" xml:lang="en-US">Class of Warrant or Right, Call Trigger, Volume Weighted Average Price Threshold</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerVolumeWeightedAveragePriceThreshold_lbl" xml:lang="en-US">Volume weighted average price</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement" xlink:to="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement_lbl" xml:lang="en-US">The number of consecutive trading days during which the specified market price and/or trading volume conditions must be satisfied before a class of warrants or rights becomes callable.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement_lbl" xml:lang="en-US">Class of Warrant or Right, Call Trigger, Consecutive Trading Days Requirement</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerConsecutiveTradingDaysRequirement_lbl" xml:lang="en-US">Number of consecutive trading days</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold" xlink:to="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold_lbl" xml:lang="en-US">Represents average trading volume, based on the volume weighted average price of the issuer's common stock, required to be achieved over a specified consecutive trading-day period before a class of warrants or rights becomes callable</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold_lbl" xml:lang="en-US">Class of Warrant or Right, Call Trigger, Average Trading Volume Threshold</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ClassOfWarrantOrRightCallTriggerAverageTradingVolumeThreshold_lbl" xml:lang="en-US">Average trading volume</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantsAndRightsOutstandingTerm" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantsAndRightsOutstandingTerm" xlink:to="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xml:lang="en-US">Warrants and Rights Outstanding, Term</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm_lbl" xml:lang="en-US">Warrants term</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:to="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xml:lang="en-US">Stockholders' Equity Note, Stock Split, Conversion Ratio</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_lbl" xml:lang="en-US">Reverse stock split ratio</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US">Warrants issued to purchase shares</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_lbl" xml:lang="en-US">Number of common shares issuable upon exercise of outstanding warrants (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Class of Warrant or Right, Exercise Price of Warrants or Rights</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Exercise price of warrants (in dollars per share)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_lbl" xml:lang="en-US">Exercise Price (in dollars per share)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockConvertibleSharesIssuable" xlink:label="us-gaap_PreferredStockConvertibleSharesIssuable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockConvertibleSharesIssuable" xlink:to="us-gaap_PreferredStockConvertibleSharesIssuable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockConvertibleSharesIssuable_lbl" xml:lang="en-US">Preferred Stock, Convertible, Shares Issuable</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockConvertibleSharesIssuable_lbl" xml:lang="en-US">Number of shares issuable upon conversion of preferred stock</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockConvertibleConversionPrice" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockConvertibleConversionPrice" xlink:to="us-gaap_PreferredStockConvertibleConversionPrice_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xml:lang="en-US">Preferred Stock, Convertible, Conversion Price</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_PreferredStockConvertibleConversionPrice_lbl" xml:lang="en-US">Conversion price per share</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda" xlink:to="clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda_lbl" xml:lang="en-US">Number of days following the announcement of prescription drug use fee act goal date for review by FDA.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfPrescriptionDrugUseFeeActGoalByFda_lbl" xml:lang="en-US">Number of Days following the Announcement of Prescription Drug Use Fee Act Goal By FDA</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication" xlink:to="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication_lbl" xml:lang="en-US">Number of days following the announcement of receipt of written approval from FDA of its new drug application.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication_lbl" xml:lang="en-US">Number of Days following the Announcement of Receipt Of Written Approval, New Drug Application</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfReceiptOfWrittenApprovalNewDrugApplication_lbl" xml:lang="en-US">Number of days following the date of the Company's public announcement of its receipt of written approval from the FDA</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug" xlink:to="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug_lbl" xml:lang="en-US">Number of days following the announcement of quarterly gross revenue from sales of iopofosine I 131.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug_lbl" xml:lang="en-US">Number Of Days Following the Announcement Of Quarterly Gross Revenue From Sales Of Drug</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfDaysFollowingAnnouncementOfQuarterlyGrossRevenueFromSalesOfDrug_lbl" xml:lang="en-US">Number of days following the announcement of quarterly gross revenue from sales of iopofosine I 131.</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate" xlink:label="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate" xlink:to="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate_lbl" xml:lang="en-US">Threshold amount of quarterly gross revenues trigger for expiry of warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate_lbl" xml:lang="en-US">Threshold Quarterly Gross Revenues Trigger, For Warrant Expiry Date</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ThresholdQuarterlyGrossRevenuesTriggerForWarrantExpiryDate_lbl" xml:lang="en-US">Threshold amount of quarterly gross revenues trigger for expiry of warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US">Shares issued</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ClassOfWarrantOrRightOutstanding" xlink:to="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Class of Warrant or Right, Outstanding</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding_lbl" xml:lang="en-US">Warrants outstanding</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromWarrantExercises" xlink:label="us-gaap_ProceedsFromWarrantExercises" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromWarrantExercises" xlink:to="us-gaap_ProceedsFromWarrantExercises_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromWarrantExercises_lbl" xml:lang="en-US">Proceeds from Warrant Exercises</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ProceedsFromWarrantExercises_lbl" xml:lang="en-US">Proceeds from exercise of warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_lbl" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements_lbl" xml:lang="en-US">Settlement of warrants to equity</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_WarrantsIssuedToPurchaseOfCommonStock" xlink:label="clrb_WarrantsIssuedToPurchaseOfCommonStock" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_WarrantsIssuedToPurchaseOfCommonStock" xlink:to="clrb_WarrantsIssuedToPurchaseOfCommonStock_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_WarrantsIssuedToPurchaseOfCommonStock_lbl" xml:lang="en-US">Warrants issued to purchase of common stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_WarrantsIssuedToPurchaseOfCommonStock_lbl" xml:lang="en-US">Warrants Issued to Purchase of Common Stock</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_WarrantsIssuedToPurchaseOfCommonStock_lbl" xml:lang="en-US">Warrants issued</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ExerciseOfWarrantsIntoCommonSharesShares" xlink:label="clrb_ExerciseOfWarrantsIntoCommonSharesShares" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ExerciseOfWarrantsIntoCommonSharesShares" xlink:to="clrb_ExerciseOfWarrantsIntoCommonSharesShares_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ExerciseOfWarrantsIntoCommonSharesShares_lbl" xml:lang="en-US">Number of shares issued at exercise of warrants into common shares.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ExerciseOfWarrantsIntoCommonSharesShares_lbl" xml:lang="en-US">Exercise of Warrants Into Common Shares, Shares</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ExerciseOfWarrantsIntoCommonSharesShares_lbl" xml:lang="en-US">Exercise of warrants into common shares (in shares)</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ClassOfWarrantOrRightPricePerWarrantOrRight" xlink:label="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight" xlink:to="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight_lbl" xml:lang="en-US">Price of each class of warrant or right.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight_lbl" xml:lang="en-US">Class of Warrant or Right, Price Per Warrant or Right</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ClassOfWarrantOrRightPricePerWarrantOrRight_lbl" xml:lang="en-US">Price per warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_NumberOfWarrantsIssued" xlink:label="clrb_NumberOfWarrantsIssued" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_NumberOfWarrantsIssued" xlink:to="clrb_NumberOfWarrantsIssued_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_NumberOfWarrantsIssued_lbl" xml:lang="en-US">Number of new warrants issued in exchange of each warrant exercised.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_NumberOfWarrantsIssued_lbl" xml:lang="en-US">Number Of Warrants Issued</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_NumberOfWarrantsIssued_lbl" xml:lang="en-US">Number of warrants issued</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight" xlink:label="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight" xlink:to="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight_lbl" xml:lang="en-US">Price paid per share or per unit of warrant or right.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight_lbl" xml:lang="en-US">Class of Warrant or Right, Price Paid Per Warrant or Right</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ClassOfWarrantOrRightPricePaidPerWarrantOrRight_lbl" xml:lang="en-US">Price paid per warrant</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ProceedsFromIssuanceAndExerciseOfWarrants" xlink:label="clrb_ProceedsFromIssuanceAndExerciseOfWarrants" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ProceedsFromIssuanceAndExerciseOfWarrants" xlink:to="clrb_ProceedsFromIssuanceAndExerciseOfWarrants_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ProceedsFromIssuanceAndExerciseOfWarrants_lbl" xml:lang="en-US">The cash inflow from issuance and exercise of warrants during the period.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ProceedsFromIssuanceAndExerciseOfWarrants_lbl" xml:lang="en-US">Proceeds From Issuance And Exercise Of Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ProceedsFromIssuanceAndExerciseOfWarrants_lbl" xml:lang="en-US">Proceeds from issuance and exercise of warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentySixMayPreFundedWarrantsMember" xlink:label="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember" xlink:to="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2026 May Pre-Funded Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Six May Pre-Funded Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentySixMayPreFundedWarrantsMember_lbl" xml:lang="en-US">2026 May Pre-Funded Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2026 May Tranche A Common Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Six May Tranche A Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentySixMayTrancheCommonWarrantsMember_lbl" xml:lang="en-US">2026 May Tranche A Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2026 May Tranche B Common Warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Six May Tranche B Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentySixMayTrancheBCommonWarrantsMember_lbl" xml:lang="en-US">2026 May Tranche B Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2025 October series I common warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Five October Series One Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesOneCommonWarrantsMember_lbl" xml:lang="en-US">2025 October Series I Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2025 October series II common warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Five October Series Two Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFiveOctoberSeriesTwoCommonWarrantsMember_lbl" xml:lang="en-US">2025 October Series II Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember" xlink:label="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember" xlink:to="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to 2025 July common warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember_lbl" xml:lang="en-US">Two Thousand Twenty Five July Common Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_TwoThousandTwentyFiveJulyCommonWarrantsMember_lbl" xml:lang="en-US">2025 July Common Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_WarrantsExpirationDate" xlink:label="clrb_WarrantsExpirationDate" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_WarrantsExpirationDate" xlink:to="clrb_WarrantsExpirationDate_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_WarrantsExpirationDate_lbl" xml:lang="en-US">Expiry date of warrants held.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_WarrantsExpirationDate_lbl" xml:lang="en-US">Warrants Expiration Date</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_WarrantsExpirationDate_lbl" xml:lang="en-US">Expiration Date</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeAxis" xlink:label="us-gaap_MeasurementInputTypeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputTypeAxis_lbl" xml:lang="en-US">Measurement Input Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputTypeDomain" xlink:label="us-gaap_MeasurementInputTypeDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputTypeDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputTypeDomain_lbl" xml:lang="en-US">Measurement Input Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputExpectedDividendRateMember" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputExpectedDividendRateMember" xlink:to="us-gaap_MeasurementInputExpectedDividendRateMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember_lbl" xml:lang="en-US">Dividend</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember_lbl" xml:lang="en-US">Dividend</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_October2022WarrantsMember" xlink:label="clrb_October2022WarrantsMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_October2022WarrantsMember" xlink:to="clrb_October2022WarrantsMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_October2022WarrantsMember_lbl" xml:lang="en-US">Represents information pertaining to October 2022 warrants.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_October2022WarrantsMember_lbl" xml:lang="en-US">October 2022 Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_October2022WarrantsMember_lbl" xml:lang="en-US">October 2022 Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantsAndRightsOutstandingMeasurementInput" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantsAndRightsOutstandingMeasurementInput" xlink:to="us-gaap_WarrantsAndRightsOutstandingMeasurementInput_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput_lbl" xml:lang="en-US">Warrants and Rights Outstanding, Measurement Input</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput_lbl" xml:lang="en-US">Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xml:lang="en-US">Fair Value, Hierarchy [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_lbl" xml:lang="en-US">Fair Value Hierarchy [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="us-gaap_FairValueInputsLevel1Member" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel1Member" xlink:to="us-gaap_FairValueInputsLevel1Member_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xml:lang="en-US">Fair Value, Inputs, Level 1 [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xml:lang="en-US">Level 1</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="us-gaap_FairValueInputsLevel3Member" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel3Member" xlink:to="us-gaap_FairValueInputsLevel3Member_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xml:lang="en-US">Fair Value, Inputs, Level 3 [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xml:lang="en-US">Level 3</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis_lbl" xml:lang="en-US">Measurement Frequency [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementFrequencyDomain" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_lbl" xml:lang="en-US">Measurement Frequency [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="us-gaap_FairValueMeasurementsRecurringMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementsRecurringMember" xlink:to="us-gaap_FairValueMeasurementsRecurringMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xml:lang="en-US">Fair Value, Recurring [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueMeasurementsRecurringMember_lbl" xml:lang="en-US">Recurring basis</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputPriceVolatilityMember" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputPriceVolatilityMember" xlink:to="us-gaap_MeasurementInputPriceVolatilityMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember_lbl" xml:lang="en-US">Volatility</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember_lbl" xml:lang="en-US">Volatility</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputRiskFreeInterestRateMember" xlink:to="us-gaap_MeasurementInputRiskFreeInterestRateMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember_lbl" xml:lang="en-US">Risk-free interest rate</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember_lbl" xml:lang="en-US">Risk-free interest rate</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MeasurementInputExpectedTermMember" xlink:label="us-gaap_MeasurementInputExpectedTermMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MeasurementInputExpectedTermMember" xlink:to="us-gaap_MeasurementInputExpectedTermMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xml:lang="en-US">Expected life (years)</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_MeasurementInputExpectedTermMember_lbl" xml:lang="en-US">Expected life (years)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantMember" xlink:label="us-gaap_WarrantMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WarrantMember" xlink:to="us-gaap_WarrantMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WarrantMember_lbl" xml:lang="en-US">Warrants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_WarrantMember_lbl" xml:lang="en-US">Warrants</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_WarrantMember_lbl" xml:lang="en-US">Warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward" xlink:to="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_lbl" xml:lang="en-US">Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_lbl" xml:lang="en-US">Changes in the fair market value of the warrants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US">Ending warrant fair value</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue_lbl" xml:lang="en-US">Beginning warrant fair value</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings" xlink:to="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_lbl" xml:lang="en-US">Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings_lbl" xml:lang="en-US">Change in warrant fair value</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueRecurringBasisUnobservableInputReconciliationLiabilityGainLossStatementOfIncomeExtensibleList" xlink:label="us-gaap_FairValueRecurringBasisUnobservableInputReconciliationLiabilityGainLossStatementOfIncomeExtensibleList" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueRecurringBasisUnobservableInputReconciliationLiabilityGainLossStatementOfIncomeExtensibleList" xlink:to="us-gaap_FairValueRecurringBasisUnobservableInputReconciliationLiabilityGainLossStatementOfIncomeExtensibleList_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueRecurringBasisUnobservableInputReconciliationLiabilityGainLossStatementOfIncomeExtensibleList_lbl" xml:lang="en-US">Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable" xlink:label="clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable" xlink:to="clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable_lbl" xml:lang="en-US">No definition available.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ScheduleOfCompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanTable_lbl" xml:lang="en-US">Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OptionIndexedToIssuersEquityTypeAxis" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OptionIndexedToIssuersEquityTypeAxis" xlink:to="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeAxis_lbl" xml:lang="en-US">Option Indexed to Issuer's Equity, Type [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OptionIndexedToIssuersEquityTypeDomain" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OptionIndexedToIssuersEquityTypeDomain" xlink:to="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OptionIndexedToIssuersEquityTypeDomain_lbl" xml:lang="en-US">Option Indexed to Issuer's Equity, Type [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_EmployeeAndDirectorStockOptionMember" xlink:label="clrb_EmployeeAndDirectorStockOptionMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_EmployeeAndDirectorStockOptionMember" xlink:to="clrb_EmployeeAndDirectorStockOptionMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_EmployeeAndDirectorStockOptionMember_lbl" xml:lang="en-US">This member stands for employee and director stock option.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_EmployeeAndDirectorStockOptionMember_lbl" xml:lang="en-US">Employee And Director Stock Option Grants [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_EmployeeAndDirectorStockOptionMember_lbl" xml:lang="en-US">Employee and director stock option grants</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis" xlink:label="us-gaap_StatementOfIncomeLocationBalanceAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementOfIncomeLocationBalanceAxis" xlink:to="us-gaap_StatementOfIncomeLocationBalanceAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfIncomeLocationBalanceAxis_lbl" xml:lang="en-US">Location, Statement of Income, Balance [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems" xlink:label="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems" xlink:to="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems_lbl" xml:lang="en-US">No definition available.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems_lbl" xml:lang="en-US">Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_CompensationCostForShareBasedPaymentArrangementsAllocationOfShareBasedCompensationCostsByPlanLineItems_lbl" xml:lang="en-US">Employee and director stock option and stock grants:</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:to="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_lbl" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_lbl" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_lbl" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_PreferredSharesAsConvertibleIntoCommonStockMember" xlink:label="clrb_PreferredSharesAsConvertibleIntoCommonStockMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_PreferredSharesAsConvertibleIntoCommonStockMember" xlink:to="clrb_PreferredSharesAsConvertibleIntoCommonStockMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_PreferredSharesAsConvertibleIntoCommonStockMember_lbl" xml:lang="en-US">This member stands for preferred shares as convertible into common stock.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_PreferredSharesAsConvertibleIntoCommonStockMember_lbl" xml:lang="en-US">Preferred Shares As Convertible Into Common Stock [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="clrb_PreferredSharesAsConvertibleIntoCommonStockMember_lbl" xml:lang="en-US">Preferred shares on an as-converted-into-common-stock basis</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockOptionMember" xlink:label="us-gaap_StockOptionMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockOptionMember" xlink:to="us-gaap_StockOptionMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockOptionMember_lbl" xml:lang="en-US">Stock Option Activity [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_StockOptionMember_lbl" xml:lang="en-US">Stock options</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_lbl" xml:lang="en-US">NET LOSS PER SHARE</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_lbl" xml:lang="en-US">Total potentially dilutive shares</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeLeaseDescriptionTable" xlink:label="us-gaap_LesseeLeaseDescriptionTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeLeaseDescriptionTable" xlink:to="us-gaap_LesseeLeaseDescriptionTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeLeaseDescriptionTable_lbl" xml:lang="en-US">Lessee, Lease, Description [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeLeaseDescriptionLineItems" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeLeaseDescriptionLineItems" xlink:to="us-gaap_LesseeLeaseDescriptionLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xml:lang="en-US">Lessee, Lease, Description [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeLeaseDescriptionLineItems_lbl" xml:lang="en-US">Leases</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AreaOfRealEstateProperty" xlink:label="us-gaap_AreaOfRealEstateProperty" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AreaOfRealEstateProperty" xlink:to="us-gaap_AreaOfRealEstateProperty_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AreaOfRealEstateProperty_lbl" xml:lang="en-US">Area of Real Estate Property</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_AreaOfRealEstateProperty_lbl" xml:lang="en-US">Area of leased space</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecurityDeposit" xlink:label="us-gaap_SecurityDeposit" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SecurityDeposit" xlink:to="us-gaap_SecurityDeposit_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SecurityDeposit_lbl" xml:lang="en-US">Security Deposit</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SecurityDeposit_lbl" xml:lang="en-US">Security deposit paid</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue" xlink:to="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue_lbl" xml:lang="en-US">Aggregate amount of operating lease payments due over the term of the lease.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue_lbl" xml:lang="en-US">Lessee, Operating Lease, Aggregate Lease Payments Due</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDue_lbl" xml:lang="en-US">Aggregate rent due over term of amended lease</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements" xlink:to="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements_lbl" xml:lang="en-US">Aggregate amount of operating lease payments due over the term of the lease adjusted for certain rent abatements.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements_lbl" xml:lang="en-US">Lessee, Operating Lease, Aggregate Lease Payments Due, Adjusted For Rent Abatements</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_LesseeOperatingLeaseAggregateLeasePaymentsDueAdjustedForRentAbatements_lbl" xml:lang="en-US">Aggregate rent, adjusted for certain rent abatements, due over term of amended lease</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_OperatingLeaseMonthlyPaymentDue" xlink:label="clrb_OperatingLeaseMonthlyPaymentDue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_OperatingLeaseMonthlyPaymentDue" xlink:to="clrb_OperatingLeaseMonthlyPaymentDue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_OperatingLeaseMonthlyPaymentDue_lbl" xml:lang="en-US">The amount of monthly lease payment due under the terms of the lease agreement.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_OperatingLeaseMonthlyPaymentDue_lbl" xml:lang="en-US">Operating Lease, Monthly Payment Due</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_OperatingLeaseMonthlyPaymentDue_lbl" xml:lang="en-US">Monthly rent payment</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_OperatingLeaseAnnualRentEscalationPercent" xlink:label="clrb_OperatingLeaseAnnualRentEscalationPercent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_OperatingLeaseAnnualRentEscalationPercent" xlink:to="clrb_OperatingLeaseAnnualRentEscalationPercent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_OperatingLeaseAnnualRentEscalationPercent_lbl" xml:lang="en-US">The percentage increase applied to rent payments due on an annual basis per the terms of the lease agreement.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_OperatingLeaseAnnualRentEscalationPercent_lbl" xml:lang="en-US">Operating Lease, Annual Rent Escalation, Percent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_OperatingLeaseAnnualRentEscalationPercent_lbl" xml:lang="en-US">Annual percentage increase in rent due</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:to="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xml:lang="en-US">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent_lbl" xml:lang="en-US">Reasonable incremental borrowing rate (in percentage)</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_lbl" xml:lang="en-US">Remaining period of 2026</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths_lbl" xml:lang="en-US">2027</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Two</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_lbl" xml:lang="en-US">2028</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Three</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_lbl" xml:lang="en-US">2029</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due Year Four</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_lbl" xml:lang="en-US">2030</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" xlink:label="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour" xlink:to="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xml:lang="en-US">Amount of lessee's undiscounted obligation for lease payment for operating lease due after four fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due after Year Four</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFour_lbl" xml:lang="en-US">Thereafter</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Payments, Due</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_lbl" xml:lang="en-US">Total undiscounted lease payments</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:to="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xml:lang="en-US">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_lbl" xml:lang="en-US">Less: Imputed interest</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiability" xlink:label="us-gaap_OperatingLeaseLiability" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeaseLiability" xlink:to="us-gaap_OperatingLeaseLiability_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xml:lang="en-US">Operating Lease, Liability</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_OperatingLeaseLiability_lbl" xml:lang="en-US">Present value of lease liabilities</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:to="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xml:lang="en-US">Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="us-gaap_StatementBusinessSegmentsAxis" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_StatementBusinessSegmentsAxis_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xml:lang="en-US">Segments [Axis]</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain" xlink:label="us-gaap_SegmentDomain" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentDomain" xlink:to="us-gaap_SegmentDomain_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentDomain_lbl" xml:lang="en-US">Segments [Domain]</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_SingleReportableSegmentMember" xlink:label="clrb_SingleReportableSegmentMember" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_SingleReportableSegmentMember" xlink:to="clrb_SingleReportableSegmentMember_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_SingleReportableSegmentMember_lbl" xml:lang="en-US">Represents the information pertaining to single reportable segment.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_SingleReportableSegmentMember_lbl" xml:lang="en-US">Single Reportable Segment [Member]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_SingleReportableSegmentMember_lbl" xml:lang="en-US">Single reportable segment</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="us-gaap_SegmentReportingInformationLineItems" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_SegmentReportingInformationLineItems_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xml:lang="en-US">Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xml:lang="en-US">SEGMENT INFORMATION</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="us-gaap_NumberOfOperatingSegments" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfOperatingSegments" xlink:to="us-gaap_NumberOfOperatingSegments_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US">Number of Operating Segments</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_NumberOfOperatingSegments_lbl" xml:lang="en-US">Number of operating segments</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationProfitLossAbstract" xlink:label="us-gaap_SegmentReportingInformationProfitLossAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingInformationProfitLossAbstract" xlink:to="us-gaap_SegmentReportingInformationProfitLossAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentReportingInformationProfitLossAbstract_lbl" xml:lang="en-US">Segment Reporting Information, Profit (Loss) [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SegmentReportingInformationProfitLossAbstract_lbl" xml:lang="en-US">Financial data for the reportable segment</link:label>
    <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpenseAbstract" xlink:label="us-gaap_ResearchAndDevelopmentExpenseAbstract" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ResearchAndDevelopmentExpenseAbstract" xlink:to="us-gaap_ResearchAndDevelopmentExpenseAbstract_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ResearchAndDevelopmentExpenseAbstract_lbl" xml:lang="en-US">Research and Development Expense [Abstract]</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_ResearchAndDevelopmentExpenseAbstract_lbl" xml:lang="en-US">Research and development:</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam" xlink:to="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam_lbl" xml:lang="en-US">Research and development expense during the period related to the direct costs of Phase 2 study in CLOVER-WaM.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam_lbl" xml:lang="en-US">Research and Development, Direct Expense, Phase 2 Study in CLOVER-WaM</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase2StudyInCloverWam_lbl" xml:lang="en-US">Phase 2 study in WM</link:label>
    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors" />
    <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors" xlink:to="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors_lbl" />
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors_lbl" xml:lang="en-US">Research and development expense during the period related to the direct costs of Phase 1 study in pediatric tumors.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInPediatricTumors_lbl" xml:lang="en-US">Research and Development, Direct Expense, Phase 1 Study in Pediatric Tumors</link:label>
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInTripleNegativeBreastCancer_lbl" xml:lang="en-US">Research and development expense during the period related to the direct costs of Phase 1 study in triple negative breast cancer.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase1StudyInTripleNegativeBreastCancer_lbl" xml:lang="en-US">Research And Development Direct Expense Phase 1 Study In Triple Negative Breast Cancer</link:label>
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    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ResearchAndDevelopmentDirectExpensePhase3StudyInCloverWam" xlink:label="clrb_ResearchAndDevelopmentDirectExpensePhase3StudyInCloverWam" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="clrb_ResearchAndDevelopmentDirectExpenseManufacturingAndRelatedCosts_lbl" xml:lang="en-US">Research and development expense during the period related to the direct costs of manufacturing and related costs.</link:label>
    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="clrb_ResearchAndDevelopmentDirectExpenseManufacturingAndRelatedCosts_lbl" xml:lang="en-US">Research and Development, Direct Expense, Manufacturing and Related Costs</link:label>
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    <link:loc xlink:type="locator" xlink:href="clrb-20260630.xsd#clrb_ResearchAndDevelopmentIndirectExpensePreClinicalProjectsCosts" xlink:label="clrb_ResearchAndDevelopmentIndirectExpensePreClinicalProjectsCosts" />
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    <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_SegmentReportingOtherItemAmount_lbl" xml:lang="en-US">Other segment items</link:label>
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