Commitments and Contingencies	6 Months Ended
Jun. 30, 2025
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	7. Commitments and Contingencies Leases The Company leases office space under a non-cancelable operating lease in Wellesley, Massachusetts. In April 2025, the Company amended the lease to add space to the existing lease for additional fixed payments totaling $0.2 million through 2026 with an option to extend the lease through 2027 for additional fixed payments of $0.1 million. As the Company expects to exercise its option to extend the lease, the extension period is included in the lease term. Accordingly, the Company recorded an increase to operating lease right-of-use assets and operating lease liabilities of $0.2 million. There have been no other material changes to the Company’s lease agreements during the three and six months ended June 30, 2025. For additional information on the Company's operating leases, see Note 8, Commitments and Contingencies, of the consolidated financial statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024. License Agreements (Budoprutug) As a result of the Acquisition, the following legacy Tenet agreements effectively became agreements of the Company. Acelyrin Asset Purchase Agreement On January 11, 2024, Tenet entered into an asset purchase agreement (the Asset Purchase Agreement) with Acelyrin, Inc. (Acelyrin) and WH2, LLC, which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition, providing for the acquisition of certain assets of Acelyrin related to budoprutug, including certain assigned contracts. Under these assigned contracts, the Company received worldwide license (with the right to sublicense) rights to develop, manufacture, use and commercialize budoprutug for any non-oncology indication and assumed certain liabilities of Acelyrin. In addition, the Company inherited the rights and obligations, including financial obligations, under the CRH Agreement (as defined below) and the ProBioGen Agreement (as defined below). In consideration for the license and other rights the Company received under the Asset Purchase Agreement, with respect to Products (as defined in the Asset Purchase Agreement), the Company is obligated to (i) make total payments of up to $157.5 million to Acelyrin upon the achievement of various development, regulatory and commercial milestones, (ii) pay royalties in the single-digit percentages, subject to specified reductions, to Acelyrin on worldwide net sales in a given calendar year, and (iii) make non-refundable and non-creditable payments to Acelyrin on sublicense income with rates ranging from the low single digit to mid-teen percent depending on the stage of development of the most advanced licensed product incorporating or comprising budoprutug at the time of such sublicense. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the Asset Purchase Agreement as milestone achievement has not been deemed probable. CRH Agreement In connection with the Asset Purchase Agreement, in January 2024 Tenet was assigned a license agreement with Cancer Research Technology Limited (CRH) and, in connection with such assignment, Tenet entered into an amended and restated license agreement with CRH (the CRH Agreement) which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition. The CRH Agreement granted the Company a worldwide exclusive license (other than specified patent rights and materials, which are licensed to the Company on a non-exclusive basis) to research, develop, test, manufacture or sell certain licensed products related to budoprutug, for all therapeutic uses except for oncology indications. The Company is permitted to grant a sublicense under these licenses with CRH’s prior written consent. The Company is obligated to pay CRH a mid-five figure digit fee on each anniversary of the effective date and up to an aggregate of £106.8 million ($146.3 million as of June 30, 2025) upon the achievement of specified development, regulatory, commercial and sales milestone events, including: (i) payments of up to mid-six figure digits in pounds sterling for certain development milestones, (ii) payments of up to low-eight figures in pounds sterling per indication (for up to three indications) for certain regulatory and commercial milestones and (iii) payments up to mid-eight figures in pounds sterling for certain sales milestones. The Company is also obligated to pay tiered royalties ranging from a rate in the mid-single digit to high-single digit percentage on net sales. The Company is also responsible for a sublicensing revenue payment ranging from a rate in the mid-single digit to mid-double digits for any sublicense revenue. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the CRH Agreement as milestone achievement has not been deemed probable. ProBioGen Agreement Under the Asset Purchase Agreement, Tenet was assigned a cell line development, manufacturing services and license agreement (the ProBioGen Agreement) originally entered into by ValenzaBio, Inc. and ProBioGen AG (ProBioGen) in February 2021, which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition. The ProBioGen Agreement granted the Company a non-exclusive license to use cell lines in which ProBioGen’s proprietary technology is applied to research, develop, manufacture, use, sell, offer to sell, import or export budoprutug. This license includes a non-exclusive sublicense by ProBioGen of certain third-party patent rights, limited to the use of budoprutug. The Company is obligated to (i) make payments of up to €10.0 million ($11.7 million as of June 30, 2025) upon the achievement of certain development, manufacturing and commercial milestones, including the start of a Phase 2 clinical trial for budoprutug, and (ii) make milestone payments of up to €7.0 million ($8.2 million as of June 30, 2025) upon the achievement of certain sales milestones. If the Company elects to contract ProBioGen to perform certain manufacturing services for budoprutug, the milestone payments would be reduced by €1.1 million ($1.2 million as of June 30, 2025). The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. During the three and six months ended June 30, 2025, the Company recorded $0.8 million of research and development expense related to a milestone. License Agreement (CLYM116) On January 8, 2025, the Company entered into the Mabworks Agreement, pursuant to which Mabworks granted to the Company (i) an exclusive (even as to Mabworks and its affiliates), sublicensable right and license under certain patent rights and related know-how (the Licensed Intellectual Property) to develop, manufacture and commercialize Mabworks’ proprietary antibodies associated with Mabworks’ proprietary antibody program, CLYM116 and products containing CLYM116 (Licensed Products) outside of Greater China, (ii) a non-exclusive, sublicensable right and license under the Licensed Intellectual Property to manufacture CLYM116 and Licensed Products in Greater China (the Licensed Territory) and (iii) a non-exclusive, sublicensable right and license under the Licensed Intellectual Property to develop CLYM116 and Licensed Products in Greater China in connection with certain global clinical studies (as described below). Under the terms of the Mabworks Agreement, the Company paid to Mabworks a $9.0 million upfront payment, and the Company is obligated to pay a total of up to $30.0 million upon the achievement of certain development and regulatory milestones pertaining to the first indication for a Licensed Product, additional lower amounts upon the achievement of certain development and regulatory milestones pertaining to up to two additional indications for a Licensed Product and a total of up to $832.0 million upon the achievement of certain commercial milestones for all Licensed Products. In addition, the Company is also obligated to pay Mabworks tiered royalties in the low-to mid-single-digit percentages on aggregate annual net sales of all Licensed Products in the Licensed Territory. The Company is obligated to pay royalties on a Licensed Product-by-Licensed Product and country-by-country basis from the date of the first commercial sale in such country until the latest of: (i) the expiration of the last valid claim on the Licensed Intellectual Property covering the composition of matter of CLYM116 in such Licensed Product in such country; and (ii) ten years following the first commercial sale of such Licensed Product in such country (each, a Royalty Term). The royalty rate is subject to reduction under certain circumstances. In the event that the Company grants sublicenses under the Licensed Intellectual Property, the Company will be obligated to pay Mabworks a percentage, in the mid-single-digits to low-double-digits, of certain consideration received under such sublicenses. The Company agreed to use commercially reasonable efforts to develop, obtain regulatory approval for and commercialize a Licensed Product in the U.S. The Company has also granted Mabworks a right of first refusal to develop and commercialize in the China Territory any product the Company controls that contains an antibody directed to tumor necrosis factor ligand superfamily member 13 (APRIL). Mabworks has agreed not to exploit in the Licensed Territory any product that is directed to APRIL during the term of the Mabworks Agreement. The Mabworks Agreement also contains a mechanism for the parties to collaborate on global clinical studies in the future, where the Company has a right to perform clinical studies in Greater China with Mabworks’ approval in the event that Mabworks elects not to participate in such global clinical studies. Unless earlier terminated, the Mabworks Agreement will expire on the expiration of the last to expire Royalty Term. Either party may terminate the Mabworks Agreement for the other party’s material breach, following a customary notice and cure period, or insolvency. Additionally, the Company may terminate the Mabworks Agreement for any reason upon 60 days written notice to Mabworks. The Company recorded the upfront payment of $9.0 million as research and development expenses in the condensed consolidated statements of operations and comprehensive loss in the first quarter of 2025. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the Mabworks Agreement as milestone achievement has not been deemed probable. Legal Proceedings From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of its business activities. The Company records accruals for estimated losses when available information indicates a loss is probable and reasonably estimable. Significant judgment is required to determine both probability and the estimated amount. As of the date of these unaudited condensed consolidated financial statements, the Company is not party to any material legal matters or claims. Indemnification In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Pursuant to such agreements, the Company may indemnify, hold harmless, and defend an indemnified party for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third-party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. The Company has never incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. The Company has also entered into indemnification agreements with its directors and officers that require the Company to indemnify its directors and officers against liabilities that may arise by reason of their status or service as directors or officers to the fullest extent permitted by Delaware corporate law. The Company currently has directors’ and officers’ insurance coverage that reduces its exposure and enables the Company to recover a portion of any future amounts paid.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2025

Commitments and Contingencies Disclosure [Abstract]

7. Commitments and Contingencies

Leases

The Company leases office space under a non-cancelable operating lease in Wellesley, Massachusetts. In April 2025, the Company amended the lease to add space to the existing lease for additional fixed payments totaling $0.2 million through 2026 with an option to extend the lease through 2027 for additional fixed payments of $0.1 million. As the Company expects to exercise its option to extend the lease, the extension period is included in the lease term. Accordingly, the Company recorded an increase to operating lease right-of-use assets and operating lease liabilities of $0.2 million.

There have been no other material changes to the Company’s lease agreements during the three and six months ended June 30, 2025. For additional information on the Company's operating leases, see Note 8, Commitments and Contingencies, of the consolidated financial statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024.

License Agreements (Budoprutug)

As a result of the Acquisition, the following legacy Tenet agreements effectively became agreements of the Company.

Acelyrin Asset Purchase Agreement

On January 11, 2024, Tenet entered into an asset purchase agreement (the Asset Purchase Agreement) with Acelyrin, Inc. (Acelyrin) and WH2, LLC, which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition, providing for the acquisition of certain assets of Acelyrin related to budoprutug, including certain assigned contracts. Under these assigned contracts, the Company received worldwide license (with the right to sublicense) rights to develop, manufacture, use and commercialize budoprutug for any non-oncology indication and assumed certain liabilities of Acelyrin.

In addition, the Company inherited the rights and obligations, including financial obligations, under the CRH Agreement (as defined below) and the ProBioGen Agreement (as defined below). In consideration for the license and other rights the Company received under the Asset Purchase Agreement, with respect to Products (as defined in the Asset Purchase Agreement), the Company is obligated to (i) make total payments of up to $157.5 million to Acelyrin upon the achievement of various development, regulatory and commercial milestones, (ii) pay royalties in the single-digit percentages, subject to specified reductions, to Acelyrin on worldwide net sales in a given calendar year, and (iii) make non-refundable and non-creditable payments to Acelyrin on sublicense income with rates ranging from the low single digit to mid-teen percent depending on the stage of development of the most advanced licensed product incorporating or comprising budoprutug at the time of such sublicense. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the Asset Purchase Agreement as milestone achievement has not been deemed probable.

CRH Agreement

In connection with the Asset Purchase Agreement, in January 2024 Tenet was assigned a license agreement with Cancer Research Technology Limited (CRH) and, in connection with such assignment, Tenet entered into an amended and restated license agreement with CRH (the CRH Agreement) which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition. The CRH Agreement granted the Company a worldwide exclusive license (other than specified patent rights and materials, which are licensed to the Company on a non-exclusive basis) to research, develop, test, manufacture or sell certain licensed products related to budoprutug, for all therapeutic uses except for oncology indications. The Company is permitted to grant a sublicense under these licenses with CRH’s prior written consent.

The Company is obligated to pay CRH a mid-five figure digit fee on each anniversary of the effective date and up to an aggregate of £106.8 million ($146.3 million as of June 30, 2025) upon the achievement of specified development, regulatory, commercial and sales milestone events, including: (i) payments of up to mid-six figure digits in pounds sterling for certain development milestones, (ii) payments of up to low-eight figures in pounds sterling per indication (for up to three indications) for certain regulatory and commercial milestones and (iii) payments up to mid-eight figures in pounds sterling for certain sales milestones. The Company is also obligated to pay tiered royalties ranging from a rate in the mid-single digit to high-single digit percentage on net sales. The Company is also responsible for a sublicensing revenue payment ranging from a rate in the mid-single digit to mid-double digits for any sublicense revenue. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the CRH Agreement as milestone achievement has not been deemed probable.

ProBioGen Agreement

Under the Asset Purchase Agreement, Tenet was assigned a cell line development, manufacturing services and license agreement (the ProBioGen Agreement) originally entered into by ValenzaBio, Inc. and ProBioGen AG (ProBioGen) in February 2021, which was subsequently transferred to the Company by operation of law upon the closing of the Acquisition. The ProBioGen Agreement granted the Company a non-exclusive license to use cell lines in which ProBioGen’s proprietary technology is applied to research, develop, manufacture, use, sell, offer to sell, import or export budoprutug. This license includes a non-exclusive sublicense by ProBioGen of certain third-party patent rights, limited to the use of budoprutug.

The Company is obligated to (i) make payments of up to €10.0 million ($11.7 million as of June 30, 2025) upon the achievement of certain development, manufacturing and commercial milestones, including the start of a Phase 2 clinical trial for budoprutug, and (ii) make milestone payments of up to €7.0 million ($8.2 million as of June 30, 2025) upon the achievement of certain sales milestones. If the Company elects to contract ProBioGen to perform certain manufacturing services for budoprutug, the milestone payments would be reduced by €1.1 million ($1.2 million as of June 30, 2025). The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. During the three and six months ended June 30, 2025, the Company recorded $0.8 million of research and development expense related to a milestone.

License Agreement (CLYM116)

On January 8, 2025, the Company entered into the Mabworks Agreement, pursuant to which Mabworks granted to the Company (i) an exclusive (even as to Mabworks and its affiliates), sublicensable right and license under certain patent rights and related know-how (the Licensed Intellectual Property) to develop, manufacture and commercialize Mabworks’ proprietary antibodies associated with Mabworks’ proprietary antibody program, CLYM116 and products containing CLYM116 (Licensed Products) outside of Greater China, (ii) a non-exclusive, sublicensable right and license under the Licensed Intellectual Property to manufacture CLYM116 and Licensed Products in Greater China (the Licensed Territory) and (iii) a non-exclusive, sublicensable right and license under the Licensed Intellectual Property to develop CLYM116 and Licensed Products in Greater China in connection with certain global clinical studies (as described below).

Under the terms of the Mabworks Agreement, the Company paid to Mabworks a $9.0 million upfront payment, and the Company is obligated to pay a total of up to $30.0 million upon the achievement of certain development and regulatory milestones pertaining to the first indication for a Licensed Product, additional lower amounts upon the achievement of certain development and regulatory milestones pertaining to up to two additional indications for a Licensed Product and a total of up to $832.0 million upon the achievement of certain commercial milestones for all Licensed Products. In addition, the Company is also obligated to pay Mabworks tiered royalties in the low-to mid-single-digit percentages on aggregate annual net sales of all Licensed Products in the Licensed Territory. The Company is obligated to pay royalties on a Licensed Product-by-Licensed Product and country-by-country basis from the date of the first commercial sale in such country until the latest of: (i) the expiration of the last valid claim on the Licensed Intellectual Property covering the composition of matter of CLYM116 in such Licensed Product in such country; and (ii) ten years following the first commercial sale of such Licensed Product in such country (each, a Royalty Term). The royalty rate is subject to reduction under certain circumstances. In the event that the Company grants sublicenses under the Licensed Intellectual Property, the Company will be obligated to pay Mabworks a percentage, in the mid-single-digits to low-double-digits, of certain consideration received under such sublicenses.

The Company agreed to use commercially reasonable efforts to develop, obtain regulatory approval for and commercialize a Licensed Product in the U.S. The Company has also granted Mabworks a right of first refusal to develop and commercialize in the China Territory any product the Company controls that contains an antibody directed to tumor necrosis factor ligand superfamily member 13 (APRIL). Mabworks has agreed not to exploit in the Licensed Territory any product that is directed to APRIL during the term of the Mabworks Agreement. The Mabworks Agreement also contains a mechanism for the parties to collaborate on global clinical studies in the future, where the Company has a right to perform clinical studies in Greater China with Mabworks’ approval in the event that Mabworks elects not to participate in such global clinical studies. Unless earlier terminated, the Mabworks Agreement will expire on the expiration of the last to expire Royalty Term. Either party may terminate the Mabworks Agreement for the other party’s material breach, following a customary notice and cure period, or insolvency. Additionally, the Company may terminate the Mabworks Agreement for any reason upon 60 days written notice to Mabworks.

The Company recorded the upfront payment of $9.0 million as research and development expenses in the condensed consolidated statements of operations and comprehensive loss in the first quarter of 2025. The Company records expense related to milestone payments when achievement of the milestone is assessed as probable. As of June 30, 2025, the Company has not recorded expense related to milestone payments under the Mabworks Agreement as milestone achievement has not been deemed probable.

Legal Proceedings

From time to time, the Company may have certain contingent liabilities that arise in the ordinary course of its business activities. The Company records accruals for estimated losses when available information indicates a loss is probable and reasonably estimable. Significant judgment is required to determine both probability and the estimated amount. As of the date of these unaudited condensed consolidated financial statements, the Company is not party to any material legal matters or claims.

Indemnification

In the ordinary course of business, the Company enters into agreements that may include indemnification provisions. Pursuant to such agreements, the Company may indemnify, hold harmless, and defend an indemnified party for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third-party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments the Company could be required to make under these provisions is not determinable. The Company has never incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. The Company has also entered into indemnification agreements with its directors and officers that require the Company to indemnify its directors and officers against liabilities that may arise by reason of their status or service as directors or officers to the fullest extent permitted by Delaware corporate law. The Company currently has directors’ and officers’ insurance coverage that reduces its exposure and enables the Company to recover a portion of any future amounts paid.