Sale of assets	3 Months Ended
Mar. 31, 2026
Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]
Asset acquisition	3. Sale of assets In October 2025, the Company entered into an Asset Purchase and Sale Agreement, as amended (APA) with Biossil, Inc. (Biossil), pursuant to which Biossil acquired all of the Company’s right, title and interest in and to its assets related to avasopasem and rucosopasem and all other dismutase mimetics assets (the Transaction). The assets consisted of intellectual property rights related to dismutase mimetics and inventory of avasopasem and rucosopasem; there was no carrying value for these assets. Biossil assumed the Company’s existing agreements related to these assets. The Company received consideration from Biossil in the form of an upfront payment in October 2025 of $3.5 million, and is eligible to receive further payments upon the achievement of future regulatory and commercial milestones of up to $75.0 million, and received contingent value rights of up to $30.0 million should Biossil enter into an out-license for topical applications. The Company accounted for the Transaction as a sale of a nonfinancial asset group in accordance with ASC 610-20, Other Income-Gains and Losses from Derecognition of Nonfinancial Assets, and followed the principles of ASC 606, Revenue from Contracts with Customers. Future regulatory and commercial milestone payments and potential payments pursuant to the contingent value rights are considered variable consideration and fully constrained at the time of the sale and again at March 31, 2026, as it was determined that it was not probable that the variable consideration related to the contingent milestone payments and contingent value right payments will be received. The contingent milestone and contingent value right payments will be recognized if and when it becomes probable that the underlying milestones or events will be achieved and payments will be received. The Company transferred control of the nonfinancial asset group in October 2025 and recognized a gain of $3.5 million in the consolidated statements of operations related to the sale of dismutase mimetics assets and a gain of $151.0 million related to the extinguishment of the royalty purchase liability. In connection with acquiring these assets, the Company assigned and Biossil assumed all of the Company’s rights and obligations under the Royalty Agreement with Blackstone (see Note 7).

Sale of assets

3 Months Ended

Mar. 31, 2026

Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]

Asset acquisition

Sale of assets

In October 2025, the Company entered into an Asset Purchase and Sale Agreement, as amended (APA) with Biossil, Inc. (Biossil), pursuant to which Biossil acquired all of the Company’s right, title and interest in and to its assets related to avasopasem and rucosopasem and all other dismutase mimetics assets (the Transaction). The assets consisted of intellectual property rights related to dismutase mimetics and inventory of avasopasem and rucosopasem; there was no carrying value for these assets. Biossil assumed the Company’s existing agreements related to these assets.

The Company received consideration from Biossil in the form of an upfront payment in October 2025 of $3.5 million, and is eligible to receive further payments upon the achievement of future regulatory and commercial milestones of up to $75.0 million, and received contingent value rights of up to $30.0 million should Biossil enter into an out-license for topical applications. The Company accounted for the Transaction as a sale of a nonfinancial asset group in accordance with ASC 610-20, Other Income-Gains and Losses from Derecognition of Nonfinancial Assets, and followed the principles of ASC 606, Revenue from Contracts with Customers. Future regulatory and commercial milestone payments and potential payments pursuant to the contingent value rights are considered variable consideration and fully constrained at the time of the sale and again at March 31, 2026, as it was determined that it was not probable that the variable consideration related to the contingent milestone payments and contingent value right payments will be received. The contingent milestone and contingent value right payments will be recognized if and when it becomes probable that the underlying milestones or events will be achieved and payments will be received. The Company transferred control of the nonfinancial asset group in October 2025 and recognized a gain of $3.5 million in the consolidated statements of operations related to the sale of dismutase mimetics assets and a gain of $151.0 million related to the extinguishment of the royalty purchase liability.

In connection with acquiring these assets, the Company assigned and Biossil assumed all of the Company’s rights and obligations under the Royalty Agreement with Blackstone (see Note 7).