<?xml version="1.0" encoding="utf-8"?>
<!--XBRL document created with Toppan Merrill Bridge  11.5.1.0 -->
<!--Based on XBRL 2.1-->
<!--Created on: 10/29/2026 1:24:41 PM-->
<!--Modified on: 10/29/2026 1:24:41 PM-->
<link:linkbase xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink">
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#StatementConsolidatedBalanceSheets" roleURI="http://www.ptcbio.com/role/StatementConsolidatedBalanceSheets" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#StatementConsolidatedStatementsOfOperations" roleURI="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfOperations" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#StatementConsolidatedStatementsOfComprehensiveLossIncome" roleURI="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfComprehensiveLossIncome" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#StatementConsolidatedStatementsOfCashFlows" roleURI="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfCashFlows" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureSummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" roleURI="http://www.ptcbio.com/role/DisclosureSummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureInventoryDetails" roleURI="http://www.ptcbio.com/role/DisclosureInventoryDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesUnrealizedGainsLossesDetails" roleURI="http://www.ptcbio.com/role/DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesUnrealizedGainsLossesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleSecuritiesDetails" roleURI="http://www.ptcbio.com/role/DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleSecuritiesDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureAccountsPayableAndAccruedExpensesComponentsDetails" roleURI="http://www.ptcbio.com/role/DisclosureAccountsPayableAndAccruedExpensesComponentsDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureNetLossIncomePerShareNumeratorAndDenominatorDetails" roleURI="http://www.ptcbio.com/role/DisclosureNetLossIncomePerShareNumeratorAndDenominatorDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureDebtConvertibleNotesInterestExpenseDetails" roleURI="http://www.ptcbio.com/role/DisclosureDebtConvertibleNotesInterestExpenseDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureIntangibleAssetsAndGoodwillFutureAmortizationDetails" roleURI="http://www.ptcbio.com/role/DisclosureIntangibleAssetsAndGoodwillFutureAmortizationDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <roleRef xlink:type="simple" xlink:href="tmb-20260930.xsd#DisclosureSegmentInformationSignificantExpensesBySegmentDetails" roleURI="http://www.ptcbio.com/role/DisclosureSegmentInformationSignificantExpensesBySegmentDetails" xmlns="http://www.xbrl.org/2003/linkbase" />
  <link:arcroleRef arcroleURI="https://xbrl.org/2023/arcrole/summation-item" xlink:type="simple" xlink:href="https://www.xbrl.org/2023/calculation-1.1.xsd#summation-item" />
  <calculationLink xlink:role="http://www.ptcbio.com/role/StatementConsolidatedBalanceSheets" xlink:type="extended" xlink:title="995200100 - Statement - Consolidated Balance Sheets" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets" xlink:label="Assets" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="us-gaap_AssetsCurrent_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639288770775374228" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketableSecuritiesCurrent" xlink:label="us-gaap_MarketableSecuritiesCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639288770775374228" xlink:to="us-gaap_MarketableSecuritiesCurrent_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="us-gaap_ReceivablesNetCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639288770775374228" xlink:to="us-gaap_ReceivablesNetCurrent_639288770775374228" order="3" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639288770775374228" xlink:to="us-gaap_InventoryNet_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_AssetsCurrent_639288770775374228" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent_639288770775374228" order="5" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="us-gaap_PropertyPlantAndEquipmentNet_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="us-gaap_PropertyPlantAndEquipmentNet_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="us-gaap_IntangibleAssetsNetExcludingGoodwill_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="us-gaap_IntangibleAssetsNetExcludingGoodwill_639288770775374228" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill" xlink:label="us-gaap_Goodwill_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="us-gaap_Goodwill_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset_639288770775374228" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_DepositsAndOtherAssetsNoncurrent" xlink:label="ptct_DepositsAndOtherAssetsNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="Assets" xlink:to="ptct_DepositsAndOtherAssetsNoncurrent_639288770775374228" order="6" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="LiabilitiesAndStockholdersEquity" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities" xlink:label="us-gaap_Liabilities_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_Liabilities_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="us-gaap_LiabilitiesCurrent_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtCurrent" xlink:label="us-gaap_LongTermDebtCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="us-gaap_LongTermDebtCurrent_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="us-gaap_ContractWithCustomerLiabilityCurrent_639288770775374228" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent_639288770775374228" order="4" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseLiabilityCurrent" xlink:label="us-gaap_FinanceLeaseLiabilityCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="us-gaap_FinanceLeaseLiabilityCurrent_639288770775374228" order="5" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_LiabilitySaleOfFutureRoyaltiesCurrent" xlink:label="ptct_LiabilitySaleOfFutureRoyaltiesCurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_LiabilitiesCurrent_639288770775374228" xlink:to="ptct_LiabilitySaleOfFutureRoyaltiesCurrent_639288770775374228" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="us-gaap_LongTermDebtNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="us-gaap_LongTermDebtNoncurrent_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent_639288770775374228" order="3" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseLiabilityNoncurrent" xlink:label="us-gaap_FinanceLeaseLiabilityNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="us-gaap_FinanceLeaseLiabilityNoncurrent_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_LiabilitySaleOfFutureRoyaltiesNoncurrent" xlink:label="ptct_LiabilitySaleOfFutureRoyaltiesNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="ptct_LiabilitySaleOfFutureRoyaltiesNoncurrent_639288770775374228" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_Liabilities_639288770775374228" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_639288770775374228" order="6" use="optional" weight="1" priority="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity" xlink:label="us-gaap_StockholdersEquity_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_StockholdersEquity_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639288770775374228" xlink:to="us-gaap_CommonStockValue_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="us-gaap_AdditionalPaidInCapital_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639288770775374228" xlink:to="us-gaap_AdditionalPaidInCapital_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639288770775374228" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_639288770775374228" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_StockholdersEquity_639288770775374228" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit_639288770775374228" order="4" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfOperations" xlink:type="extended" xlink:title="995200200 - Statement - Consolidated Statements of Operations" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="NetIncomeLoss" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="NetIncomeLoss" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="us-gaap_OtherNonoperatingIncomeExpense_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" xlink:to="us-gaap_OtherNonoperatingIncomeExpense_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="us-gaap_InterestIncomeExpenseNonoperatingNet_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" xlink:to="us-gaap_InterestIncomeExpenseNonoperatingNet_639288770775374228" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss" xlink:label="us-gaap_OperatingIncomeLoss_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_639288770775374228" xlink:to="us-gaap_OperatingIncomeLoss_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639288770775374228" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses" xlink:label="us-gaap_OperatingExpenses_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingIncomeLoss_639288770775374228" xlink:to="us-gaap_OperatingExpenses_639288770775374228" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_CostOfGoodsAndServiceExcludingAmortizationOfIntangibleAssets" xlink:label="ptct_CostOfGoodsAndServiceExcludingAmortizationOfIntangibleAssets_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="ptct_CostOfGoodsAndServiceExcludingAmortizationOfIntangibleAssets_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="us-gaap_AmortizationOfIntangibleAssets_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="us-gaap_AmortizationOfIntangibleAssets_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="us-gaap_ResearchAndDevelopmentExpense_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="us-gaap_ResearchAndDevelopmentExpense_639288770775374228" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="us-gaap_SellingGeneralAndAdministrativeExpense_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="us-gaap_SellingGeneralAndAdministrativeExpense_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1_639288770775374228" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_GainLossOnDispositionAndImpairmentOfTangibleAssets" xlink:label="ptct_GainLossOnDispositionAndImpairmentOfTangibleAssets_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="ptct_GainLossOnDispositionAndImpairmentOfTangibleAssets_639288770775374228" order="6" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_AcquiredInProcessResearchAndDevelopmentExpense" xlink:label="ptct_AcquiredInProcessResearchAndDevelopmentExpense_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_OperatingExpenses_639288770775374228" xlink:to="ptct_AcquiredInProcessResearchAndDevelopmentExpense_639288770775374228" order="7" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="NetIncomeLoss" xlink:to="us-gaap_IncomeTaxExpenseBenefit_639288770775374228" order="2" use="optional" weight="-1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfComprehensiveLossIncome" xlink:type="extended" xlink:title="995200300 - Statement - Consolidated Statements of Comprehensive (Loss) Income" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="ComprehensiveIncomeNetOfTax" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_NetIncomeLoss_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="ComprehensiveIncomeNetOfTax" xlink:to="us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_639288770775374228" order="3" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/StatementConsolidatedStatementsOfCashFlows" xlink:type="extended" xlink:title="995200500 - Statement - Consolidated Statements of Cash Flows" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_NetIncomeLoss_639288770775374228" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="us-gaap_DepreciationDepletionAndAmortization_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_DepreciationDepletionAndAmortization_639288770775374228" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_GainLossOnDispositionAndImpairmentOfTangibleAssetsExceptGainLossOnSale" xlink:label="ptct_GainLossOnDispositionAndImpairmentOfTangibleAssetsExceptGainLossOnSale_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_GainLossOnDispositionAndImpairmentOfTangibleAssetsExceptGainLossOnSale_639288770775374228" order="3" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense" xlink:label="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense_639288770775374228" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_NoncashRoyaltyRevenueSaleOfFutureRoyalties" xlink:label="ptct_NoncashRoyaltyRevenueSaleOfFutureRoyalties_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_NoncashRoyaltyRevenueSaleOfFutureRoyalties_639288770775374228" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_NoncashInterestExpenseLiabilityRelatedToSaleOfFutureRoyalties" xlink:label="ptct_NoncashInterestExpenseLiabilityRelatedToSaleOfFutureRoyalties_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_NoncashInterestExpenseLiabilityRelatedToSaleOfFutureRoyalties_639288770775374228" order="6" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_639288770775374228" order="7" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_ClearpointEquityInvestmentFvniUnrealizedGainLoss" xlink:label="ptct_ClearpointEquityInvestmentFvniUnrealizedGainLoss_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_ClearpointEquityInvestmentFvniUnrealizedGainLoss_639288770775374228" order="8" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss" xlink:label="us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss_639288770775374228" order="9" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt_639288770775374228" order="10" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfOtherAssets" xlink:label="us-gaap_GainLossOnSaleOfOtherAssets_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_GainLossOnSaleOfOtherAssets_639288770775374228" order="11" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_639288770775374228" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_639288770775374228" order="12" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments" xlink:label="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_639288770775530474" order="13" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_AmortizationOfFinancingCosts_639288770775530474" order="14" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_ShareBasedCompensation_639288770775530474" order="15" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ForeignCurrencyTransactionGainLossUnrealized" xlink:label="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_ForeignCurrencyTransactionGainLossUnrealized_639288770775530474" order="16" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="us-gaap_IncreaseDecreaseInInventories_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInInventories_639288770775530474" order="17" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_639288770775530474" order="18" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInReceivables" xlink:label="us-gaap_IncreaseDecreaseInReceivables_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInReceivables_639288770775530474" order="19" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInDepositOtherAssets" xlink:label="us-gaap_IncreaseDecreaseInDepositOtherAssets_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInDepositOtherAssets_639288770775530474" order="20" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_639288770775530474" order="21" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:label="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_639288770775530474" order="22" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_InducementExpenseOnRepurchaseOfConvertibleSecurities" xlink:label="ptct_InducementExpenseOnRepurchaseOfConvertibleSecurities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_InducementExpenseOnRepurchaseOfConvertibleSecurities_639288770775530474" order="23" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="us-gaap_IncreaseDecreaseInContractWithCustomerLiability_639288770775530474" order="24" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_IncreaseDecreaseInContingentConsideration" xlink:label="ptct_IncreaseDecreaseInContingentConsideration_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivities_639288770775374228" xlink:to="ptct_IncreaseDecreaseInContingentConsideration_639288770775530474" order="25" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_639288770775530474" order="1" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt" xlink:label="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_PaymentsToAcquireAvailableForSaleSecuritiesDebt_639288770775530474" order="3" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireMarketableSecurities" xlink:label="us-gaap_PaymentsToAcquireMarketableSecurities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_PaymentsToAcquireMarketableSecurities_639288770775530474" order="4" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt" xlink:label="us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromSaleOfAvailableForSaleSecuritiesDebt_639288770775530474" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities" xlink:label="us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_639288770775530474" order="6" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireIntangibleAssets" xlink:label="us-gaap_PaymentsToAcquireIntangibleAssets_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInInvestingActivities_639288770775530474" xlink:to="us-gaap_PaymentsToAcquireIntangibleAssets_639288770775530474" order="7" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="us-gaap_ProceedsFromStockOptionsExercised_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromStockOptionsExercised_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromStockPlans" xlink:label="us-gaap_ProceedsFromStockPlans_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromStockPlans_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfConvertibleDebt" xlink:label="us-gaap_RepaymentsOfConvertibleDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_RepaymentsOfConvertibleDebt_639288770775530474" order="3" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_PaymentsForRepurchaseOfConvertibleDebt" xlink:label="ptct_PaymentsForRepurchaseOfConvertibleDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="ptct_PaymentsForRepurchaseOfConvertibleDebt_639288770775530474" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeasePrincipalPayments" xlink:label="us-gaap_FinanceLeasePrincipalPayments_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_FinanceLeasePrincipalPayments_639288770775530474" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities" xlink:label="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_PaymentForContingentConsiderationLiabilityFinancingActivities_639288770775530474" order="6" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromConvertibleDebt" xlink:label="us-gaap_ProceedsFromConvertibleDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_ProceedsFromConvertibleDebt_639288770775530474" order="7" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsOfDebtIssuanceCosts" xlink:label="us-gaap_PaymentsOfDebtIssuanceCosts_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="us-gaap_PaymentsOfDebtIssuanceCosts_639288770775530474" order="8" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_PaymentsForConversionOfDebt" xlink:label="ptct_PaymentsForConversionOfDebt_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetCashProvidedByUsedInFinancingActivities_639288770775530474" xlink:to="ptct_PaymentsForConversionOfDebt_639288770775530474" order="9" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations_639288770775530474" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="us-gaap_IncomeTaxesPaidNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived" xlink:label="us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeTaxesPaidNet" xlink:to="us-gaap_IncomeTaxPaidStateAndLocalAfterRefundReceived_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxPaidForeignAfterRefundReceived" xlink:label="us-gaap_IncomeTaxPaidForeignAfterRefundReceived_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_IncomeTaxesPaidNet" xlink:to="us-gaap_IncomeTaxPaidForeignAfterRefundReceived_639288770775530474" order="2" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureSummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" xlink:type="extended" xlink:title="99940202 - Disclosure - Summary of significant accounting policies - Reconciliation of cash (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash" xlink:label="us-gaap_RestrictedCash_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="us-gaap_RestrictedCash_639288770775530474" order="2" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureInventoryDetails" xlink:type="extended" xlink:title="99940401 - Disclosure - Inventory (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet" xlink:label="us-gaap_InventoryNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryRawMaterials" xlink:label="us-gaap_InventoryRawMaterials_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryRawMaterials_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryWorkInProcess" xlink:label="us-gaap_InventoryWorkInProcess_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryWorkInProcess_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryFinishedGoods" xlink:label="us-gaap_InventoryFinishedGoods_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InventoryNet" xlink:to="us-gaap_InventoryFinishedGoods_639288770775530474" order="3" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesUnrealizedGainsLossesDetails" xlink:type="extended" xlink:title="99940503 - Disclosure - Fair value of financial instruments and marketable securities - Marketable Securities, Unrealized Gains (Losses) (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:label="AvailableForSaleDebtSecuritiesAmortizedCostBasis" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:to="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_639288770775530474" order="1" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:to="us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:label="us-gaap_AvailableForSaleSecuritiesDebtSecurities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:to="us-gaap_AvailableForSaleSecuritiesDebtSecurities_639288770775530474" order="3" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureFairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleSecuritiesDetails" xlink:type="extended" xlink:title="99940504 - Disclosure - Fair value of financial instruments and marketable securities - Available-for-sale securities (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:label="DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:to="us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_639288770775530474" order="1" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureAccountsPayableAndAccruedExpensesComponentsDetails" xlink:type="extended" xlink:title="99940601 - Disclosure - Accounts payable and accrued expenses - Components (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="AccountsPayableAndAccruedLiabilitiesCurrent" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="us-gaap_EmployeeRelatedLiabilitiesCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_EmployeeRelatedLiabilitiesCurrent_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_AccruedIncomeTaxesCurrent_639288770775530474" order="2" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_AccruedConsultingAndContractedResearchCurrent" xlink:label="ptct_AccruedConsultingAndContractedResearchCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="ptct_AccruedConsultingAndContractedResearchCurrent_639288770775530474" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_SalesAllowanceAndOtherRelatedCosts" xlink:label="ptct_SalesAllowanceAndOtherRelatedCosts_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="ptct_SalesAllowanceAndOtherRelatedCosts_639288770775530474" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_SalesRebatesCurrent" xlink:label="ptct_SalesRebatesCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="ptct_SalesRebatesCurrent_639288770775530474" order="5" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedRoyaltiesCurrent" xlink:label="us-gaap_AccruedRoyaltiesCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_AccruedRoyaltiesCurrent_639288770775530474" order="6" use="optional" weight="1" priority="2" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_AccountsPayableCurrent_639288770775530474" order="7" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_MilestonePayable" xlink:label="ptct_MilestonePayable_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="ptct_MilestonePayable_639288770775530474" order="8" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="AccountsPayableAndAccruedLiabilitiesCurrent" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent_639288770775530474" order="9" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureNetLossIncomePerShareNumeratorAndDenominatorDetails" xlink:type="extended" xlink:title="99940801 - Disclosure - Net (loss) income per share - Numerator and Denominator (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestOnConvertibleDebtNetOfTax" xlink:label="us-gaap_InterestOnConvertibleDebtNetOfTax_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:to="us-gaap_InterestOnConvertibleDebtNetOfTax_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements" xlink:label="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_IncrementalCommonSharesAttributableToShareBasedPaymentArrangements_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities" xlink:label="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities_639288770775530474" order="3" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureDebtConvertibleNotesInterestExpenseDetails" xlink:type="extended" xlink:title="99941005 - Disclosure - Debt - Convertible Notes Interest Expense (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebt" xlink:label="us-gaap_InterestExpenseDebt_1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="us-gaap_AmortizationOfFinancingCosts_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt_1" xlink:to="us-gaap_AmortizationOfFinancingCosts_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebtExcludingAmortization" xlink:label="us-gaap_InterestExpenseDebtExcludingAmortization_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_InterestExpenseDebt_1" xlink:to="us-gaap_InterestExpenseDebtExcludingAmortization_639288770775530474" order="2" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureIntangibleAssetsAndGoodwillFutureAmortizationDetails" xlink:type="extended" xlink:title="99941302 - Disclosure - Intangible assets and goodwill - Future Amortization (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_639288770775530474" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_639288770775530474" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_639288770775530474" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_639288770775530474" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_639288770775530474" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFourAndThereafter" xlink:label="ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFourAndThereafter_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFourAndThereafter_639288770775686841" order="5" use="optional" weight="1" />
  </calculationLink>
  <calculationLink xlink:role="http://www.ptcbio.com/role/DisclosureSegmentInformationSignificantExpensesBySegmentDetails" xlink:type="extended" xlink:title="99941401 - Disclosure - Segment information - Significant Expenses by Segment (Details)" xmlns="http://www.xbrl.org/2003/linkbase">
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss" xlink:label="us-gaap_NetIncomeLoss" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_639288770775686841" order="1" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_CostOfProductSalesExcludingAmortizationOfIntangibleAssetsAndRoyalties" xlink:label="ptct_CostOfProductSalesExcludingAmortizationOfIntangibleAssetsAndRoyalties_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="ptct_CostOfProductSalesExcludingAmortizationOfIntangibleAssetsAndRoyalties_639288770775686841" order="2" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LaborAndRelatedExpense" xlink:label="us-gaap_LaborAndRelatedExpense_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_LaborAndRelatedExpense_639288770775686841" order="3" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_ProgramSpend" xlink:label="ptct_ProgramSpend_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="ptct_ProgramSpend_639288770775686841" order="4" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ManufacturingCosts" xlink:label="us-gaap_ManufacturingCosts_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_ManufacturingCosts_639288770775686841" order="5" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_AdministrativeCosts" xlink:label="ptct_AdministrativeCosts_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="ptct_AdministrativeCosts_639288770775686841" order="6" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_OccupancyCosts" xlink:label="ptct_OccupancyCosts_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="ptct_OccupancyCosts_639288770775686841" order="7" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_AcquiredInProcessResearchAndDevelopmentExpense" xlink:label="ptct_AcquiredInProcessResearchAndDevelopmentExpense_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="ptct_AcquiredInProcessResearchAndDevelopmentExpense_639288770775686841" order="8" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingOtherItemAmount" xlink:label="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" order="9" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentIncomeInterest" xlink:label="us-gaap_InvestmentIncomeInterest_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="us-gaap_InvestmentIncomeInterest_639288770775686841" order="1" use="optional" weight="-1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseNonoperating" xlink:label="us-gaap_InterestExpenseNonoperating_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="us-gaap_InterestExpenseNonoperating_639288770775686841" order="2" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="us-gaap_IncomeTaxExpenseBenefit_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="us-gaap_IncomeTaxExpenseBenefit_639288770775686841" order="3" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Depreciation" xlink:label="us-gaap_Depreciation_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="us-gaap_Depreciation_639288770775686841" order="4" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="us-gaap_AmortizationOfIntangibleAssets_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="us-gaap_AmortizationOfIntangibleAssets_639288770775686841" order="5" use="optional" weight="1" />
    <loc xlink:type="locator" xlink:href="tmb-20260930.xsd#ptct_OtherExpenseSegmentNet" xlink:label="ptct_OtherExpenseSegmentNet_639288770775686841" />
    <calculationArc xlink:type="arc" xlink:arcrole="https://xbrl.org/2023/arcrole/summation-item" xlink:from="us-gaap_SegmentReportingOtherItemAmount_639288770775686841" xlink:to="ptct_OtherExpenseSegmentNet_639288770775686841" order="6" use="optional" weight="1" />
  </calculationLink>
</link:linkbase>
