License and Collaboration Agreements	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
License and Collaboration Agreements	10. License and Collaboration Agreements Sanofi Agreement In May 2024, the Company entered into a collaboration and license agreement (the “Sanofi Agreement”) with Genzyme Corporation (“Sanofi”), pursuant to which the Company granted Sanofi an exclusive license to commercialize losmapimod, an oral small molecule for the treatment of facioscapulohumeral muscular dystrophy, outside of the United States. In September 2024, the Company discontinued development of losmapimod following topline results from the Phase 3 REACH trial. On December 18, 2024, Sanofi provided written notice of termination for convenience, and the agreement terminated in its entirety on April 17, 2025. As a result, the Company is not entitled to receive any further milestone payments, royalties, or development cost reimbursements under the agreement. During the three and six months ended June 30, 2026, the Company recorded no activity related to the Sanofi Agreement. During the three and six months ended June 30, 2025, the Company recorded a reduction in research and development expenses of less than $0.1 million and $1.0 million, respectively, related to reimbursable global development activities under the agreement. CAMP4 Agreement In July 2023, the Company entered into a license agreement (the “CAMP4 Agreement”) with CAMP4 Therapeutics Corporation (“CAMP4”), pursuant to which the Company obtained a worldwide exclusive license to certain intellectual property related to CAMP4’s Diamond-Blackfan anemia (“DBA”) program. Under the terms of the agreement, the Company was responsible for development and commercialization of any licensed products, and CAMP4 would have been eligible to receive development, regulatory, and sales milestone payments, as well as royalties on net sales of licensed products. In April 2025, the Company incurred a $0.6 million preclinical milestone payment, which was recorded as research and development expense during the year ended December 31, 2025. In February 2026, the Company announced the discontinuation of its bone marrow failure syndromes program, including DBA. On April 23, 2026, the Company delivered written notice to terminate the CAMP4 Agreement for convenience. In accordance with the terms of the agreement, the termination will become effective following the applicable notice period. Upon termination, the Company will have no further obligations under the agreement, other than those that survive termination in accordance with its terms.	10. License and Collaboration Agreements Sanofi Agreement In May 2024, the Company entered into a collaboration and license agreement (the “Sanofi Agreement”) with Genzyme Corporation (“Sanofi”) pursuant to which the Company granted Sanofi an exclusive license under certain intellectual property rights to commercialize losmapimod, an oral small molecule for the treatment of facioscapulohumeral muscular dystrophy (“FSHD”), outside of the United States. Per the terms of the agreement, Sanofi made an upfront payment of $80.0 million to the Company. In September 2024, the Company announced topline data showing that it did not demonstrate a statistically significant difference between losmapimod and placebo on the primary endpoint in the Phase 3 REACH trial, and thereafter discontinued development. On December 18, 2024, the Company received written notice of Sanofi’s election to terminate for convenience the collaboration and license agreement. In accordance with the agreement, the termination became effective on April 17, 2025, which is 120 days following the date of receipt of the notice by the Company. As of the termination date, the agreement was terminated in its entirety, and the Company is not entitled to receive any further milestone payments, royalties, or global development cost reimbursement. The Company determined that the Sanofi Agreement contained three material promises: (i) the license granted to Sanofi to develop and commercialize losmapimod outside of the United States (the “losmapimod license”); (ii) the parties’ joint global development activities for losmapimod; and (iii) the Sanofi territory-specific manufacturing activities for losmapimod, subject to the terms of a supply agreement. The Company considered the guidance in ASC 606 to determine which, if any, of the components of the losmapimod agreement are performance obligations with a customer and concluded that the losmapimod license and the Sanofi territory-specific manufacturing activities are within the scope of ASC 606 because Sanofi is the Company’s customer in those transactions. The Company evaluated the losmapimod license under ASC 606 and concluded that the losmapimod license is a functional intellectual property license and is a distinct performance obligation. The Company determined that Sanofi benefited from the losmapimod license at the time of grant, and therefore the related performance obligation is satisfied at a point in time. The Company evaluated the Sanofi territory-specific manufacturing activities under ASC 606 and identified one material promise associated with manufacturing activities related to development and commercial supply of losmapimod. Given that Sanofi is not obligated to purchase any minimum amount or quantities of the development and commercial supply from the Company, the Company concluded that, for the purpose of ASC 606, the provision of manufacturing activities related to development and commercial supply of losmapimod in the Sanofi territory was an option but not a performance obligation of the Company at the inception of the Sanofi agreement and would have been accounted for if and when exercised. The Company also concluded that there is no separate material right in connection with the development and commercial supply of losmapimod, as the expected pricing was not issued at a significant and incremental discount. Therefore, the manufacturing activities were excluded as a performance obligation at the outset of the arrangement. Additionally, the Company was entitled to sales milestones and royalties from Sanofi upon future sales of losmapimod in the Sanofi territory, and revenue would have been recognized when the related sales occur. Costs that are incurred associated with the Sanofi territory-specific manufacturing activities are reimbursable from Sanofi and will be recognized as revenue. For the purposes of ASC 606, the transaction price of the Sanofi Agreement as of the outset of the arrangement consists of the upfront cash payment of $80.0 million, which was allocated to the performance obligation related to the losmapimod license and recognized as revenue during the year ended December 31, 2024. During the year ended December 31, 2025, the Company recognized no revenue associated with the upfront license payment. For the parties’ participation in global development for losmapimod, the Company concluded that those activities and cost-sharing payments related to such activities are within the scope of ASC 808, as both parties are active participants in the development activities and are exposed to significant risks and rewards of those activities under the Sanofi agreement. The Company assessed its relationship with Sanofi, the economics and nature of the global development activities, and the contractual terms of the Sanofi Agreement and concluded that, in accordance with its policy, payments to or reimbursements from Sanofi related to the global development activities will be accounted for as an increase to or reduction of research and development expenses. During the years ended December 31, 2025 and 2024, the Company recorded a reduction in research and development expenses in connection with global development activities for losmapimod of $1.0 million and $8.1 million, respectively. CAMP4 Agreement In July 2023, the Company entered into a license agreement (the “CAMP4 Agreement”) with CAMP4 Therapeutics Corporation (“CAMP4”) pursuant to which the Company received a worldwide exclusive license (including the right to sublicense) from CAMP4 to rights under its Diamond Blackfan Anemia (“DBA”) program, which includes certain small molecule compounds, composition of matter and method of use patent rights, and know-how for the Company to research, develop, manufacture, use, commercialize or otherwise exploit therapeutic products in any indication, including the grant of a sublicense under certain intellectual property rights that CAMP4 has licensed under an agreement with Children’s Medical Center Corporation (“CMCC”). The Company made an undisclosed upfront non-refundable, non-creditable payment to CAMP4. If the Company succeeds in developing and commercializing licensed products, CAMP4 will be eligible to receive (i) up to $35.0 million in development and regulatory milestone payments, and (ii) up to $35.0 million in sales milestone payments. CAMP4 is also eligible to receive royalties on worldwide net sales of licensed products ranging from mid-single digit to low-double digit, subject to potential reduction following loss of patent coverage, the launch of certain generic products or royalty stacking for licenses of third party intellectual property. The royalties will expire on a product-by-product and country-by-country basis upon the latest to occur of (i) the expiration of all valid patent claims covering the compounds in such country, (ii) the expiration of all regulatory exclusivities in such country, and (iii) 10 years following the first commercial sale in such country. The Company is responsible for the costs associated with the development and regulatory approvals of licensed products. In April 2025, the Company achieved a $0.6 million preclinical milestone that the Company recorded as research and development expense during the year ended December 31, 2025. Unless earlier terminated in accordance with its terms, the license agreement continues on a country-by-country and licensed product-by-licensed product basis until the expiration of the royalty term in each country, at which time the license agreement expires with respect to such licensed product in such country and the Company will have a fully-paid up, royalty-free and perpetual license to the licensed patent rights and know-how with respect to such licensed product in such country. CAMP4 has the right to terminate the license agreement in the event of the Company’s non-payment (subject to cure periods and tolling for bona fide disputes). CAMP4 may also terminate the license agreement if the Company challenges certain patents sublicensed to the Company by CAMP4. Either party may terminate the license agreement in its entirety for the other party’s material breach if such other party fails to cure the breach. Either party may also terminate the agreement in its entirety upon certain insolvency events involving the other party. The Company has the right to terminate the license agreement with CAMP4 for any or no reason upon prior written notice to CAMP4. The Company recognizes development and regulatory milestone payments when the underlying contingency is resolved and the consideration is paid or becomes payable. The milestone payments are capitalized or expensed depending on the nature of the associated asset as of the date of recognition.

License and Collaboration Agreements

10. License and Collaboration Agreements

In May 2024, the Company entered into a collaboration and license agreement (the “Sanofi Agreement”) with Genzyme Corporation (“Sanofi”), pursuant to which the Company granted Sanofi an exclusive license to commercialize losmapimod, an oral small molecule for the treatment of facioscapulohumeral muscular dystrophy, outside of the United States.

In September 2024, the Company discontinued development of losmapimod following topline results from the Phase 3 REACH trial. On December 18, 2024, Sanofi provided written notice of termination for convenience, and the agreement terminated in its entirety on April 17, 2025. As a result, the Company is not entitled to receive any further milestone payments, royalties, or development cost reimbursements under the agreement.

During the three and six months ended June 30, 2026, the Company recorded no activity related to the Sanofi Agreement. During the three and six months ended June 30, 2025, the Company recorded a reduction in research and development expenses of less than $0.1 million and $1.0 million, respectively, related to reimbursable global development activities under the agreement.

In July 2023, the Company entered into a license agreement (the “CAMP4 Agreement”) with CAMP4 Therapeutics Corporation (“CAMP4”), pursuant to which the Company obtained a worldwide exclusive license to certain intellectual property related to CAMP4’s Diamond-Blackfan anemia (“DBA”) program. Under the terms of the agreement, the Company was responsible for development and commercialization of any licensed products, and CAMP4 would have been eligible to receive development, regulatory, and sales milestone payments, as well as royalties on net sales of licensed products.

In April 2025, the Company incurred a $0.6 million preclinical milestone payment, which was recorded as research and development expense during the year ended December 31, 2025.

In February 2026, the Company announced the discontinuation of its bone marrow failure syndromes program, including DBA. On April 23, 2026, the Company delivered written notice to terminate the CAMP4 Agreement for convenience. In accordance with the terms of the agreement, the termination will become effective following the applicable notice period. Upon termination, the Company will have no further obligations under the agreement, other than those that survive termination in accordance with its terms.

10. License and Collaboration Agreements

In May 2024, the Company entered into a collaboration and license agreement (the “Sanofi Agreement”) with Genzyme Corporation (“Sanofi”) pursuant to which the Company granted Sanofi an exclusive license under certain intellectual property rights to commercialize losmapimod, an oral small molecule for the treatment of facioscapulohumeral muscular dystrophy (“FSHD”), outside of the United States. Per the terms of the agreement, Sanofi made an upfront payment of $80.0 million to the Company. In September 2024, the Company announced topline data showing that it did not demonstrate a statistically significant difference between losmapimod and placebo on the primary endpoint in the Phase 3 REACH trial, and thereafter discontinued development. On December 18, 2024, the Company received written notice of Sanofi’s election to terminate for convenience the collaboration and license agreement. In accordance with the agreement, the termination became effective on April 17, 2025, which is 120 days following the date of receipt of the notice by the Company.

As of the termination date, the agreement was terminated in its entirety, and the Company is not entitled to receive any further milestone payments, royalties, or global development cost reimbursement.

The Company determined that the Sanofi Agreement contained three material promises: (i) the license granted to Sanofi to develop and commercialize losmapimod outside of the United States (the “losmapimod license”); (ii) the parties’ joint global development activities for losmapimod; and (iii) the Sanofi territory-specific manufacturing activities for losmapimod, subject to the terms of a supply agreement. The Company considered the guidance in ASC 606 to determine which, if any, of the components of the losmapimod agreement are performance obligations with a customer and concluded that the losmapimod license and the Sanofi territory-specific manufacturing activities are within the scope of ASC 606 because Sanofi is the Company’s customer in those transactions.

The Company evaluated the losmapimod license under ASC 606 and concluded that the losmapimod license is a functional intellectual property license and is a distinct performance obligation. The Company determined that Sanofi benefited from the losmapimod license at the time of grant, and therefore the related performance obligation is satisfied at a point in time.

The Company evaluated the Sanofi territory-specific manufacturing activities under ASC 606 and identified one material promise associated with manufacturing activities related to development and commercial supply of losmapimod. Given that Sanofi is not obligated to purchase any minimum amount or quantities of the development and commercial supply from the Company, the Company concluded that, for the purpose of ASC 606, the provision of manufacturing activities related to development and commercial supply of losmapimod in the Sanofi territory was an option but not a performance obligation of the Company at the inception of the Sanofi agreement and would have been accounted for if and when exercised. The Company also concluded that there is no separate material right in connection with the development and commercial supply of losmapimod, as the expected pricing was not issued at a significant and incremental discount. Therefore, the manufacturing activities were excluded as a performance obligation at the outset of the arrangement. Additionally, the Company was entitled to sales milestones and royalties from Sanofi upon future sales of losmapimod in the Sanofi territory, and revenue would have been recognized when the related sales occur. Costs that are incurred associated with the Sanofi territory-specific manufacturing activities are reimbursable from Sanofi and will be recognized as revenue.

For the purposes of ASC 606, the transaction price of the Sanofi Agreement as of the outset of the arrangement consists of the upfront cash payment of $80.0 million, which was allocated to the performance obligation related to the losmapimod license and recognized as revenue during the year ended December 31, 2024. During the year ended December 31, 2025, the Company recognized no revenue associated with the upfront license payment.

For the parties’ participation in global development for losmapimod, the Company concluded that those activities and cost-sharing payments related to such activities are within the scope of ASC 808, as both parties are active participants in the development activities and are exposed to significant risks and rewards of those activities under the Sanofi agreement. The Company assessed its relationship with Sanofi, the economics and nature of the global development activities, and the contractual terms of the Sanofi Agreement and concluded that, in accordance with its policy, payments to or reimbursements from Sanofi related to the global development activities will be accounted for as an increase to or reduction of research and development expenses. During the years ended December 31, 2025 and 2024, the Company recorded a reduction in research and development expenses in connection with global development activities for losmapimod of $1.0 million and $8.1 million, respectively.

In July 2023, the Company entered into a license agreement (the “CAMP4 Agreement”) with CAMP4 Therapeutics Corporation (“CAMP4”) pursuant to which the Company received a worldwide exclusive license (including the right to sublicense) from CAMP4 to rights under its Diamond Blackfan Anemia (“DBA”) program, which includes certain small molecule compounds, composition of matter and method of use patent rights, and

know-how

for the Company to research, develop, manufacture, use, commercialize or otherwise exploit therapeutic products in any indication, including the grant of a sublicense under certain intellectual property rights that CAMP4 has licensed under an agreement with Children’s Medical Center Corporation (“CMCC”).

The Company made an undisclosed upfront

non-refundable,

non-creditable

payment to CAMP4. If the Company succeeds in developing and commercializing licensed products, CAMP4 will be eligible to receive (i) up to $35.0 million in development and regulatory milestone payments, and (ii) up to $35.0 million in sales milestone payments. CAMP4 is also eligible to receive royalties on worldwide net sales of licensed products ranging from

mid-single

digit to

low-double

digit, subject to potential reduction following loss of patent coverage, the launch of certain generic products or royalty stacking for licenses of third party intellectual property. The royalties will expire on a

product-by-product

and

country-by-country

basis upon the latest to occur of (i) the expiration of all valid patent claims covering the compounds in such country, (ii) the expiration of all regulatory exclusivities in such country, and (iii) 10 years following the first commercial sale in such country. The Company is responsible for the costs associated with the development and regulatory approvals of licensed products. In April 2025, the Company achieved a $0.6 million preclinical milestone that the Company recorded as research and development expense during the year ended December 31, 2025.

Unless earlier terminated in accordance with its terms, the license agreement continues on a

country-by-country

and licensed

product-by-licensed

product basis until the expiration of the royalty term in each country, at which time the license agreement expires with respect to such licensed product in such country and the Company will have a fully-paid up, royalty-free and perpetual license to the licensed patent rights and

know-how

with respect to such licensed product in such country. CAMP4 has the right to terminate the license agreement in the event of the Company’s

non-payment

(subject to cure periods and tolling for bona fide disputes). CAMP4 may also terminate the license agreement if the Company challenges certain patents sublicensed to the Company by CAMP4. Either party may terminate the license agreement in its entirety for the other party’s material breach if such other party fails to cure the breach. Either party may also terminate the agreement in its entirety upon certain insolvency events involving the other party. The Company has the right to terminate the license agreement with CAMP4 for any or no reason upon prior written notice to CAMP4.

The Company recognizes development and regulatory milestone payments when the underlying contingency is resolved and the consideration is paid or becomes payable. The milestone payments are capitalized or expensed depending on the nature of the associated asset as of the date of recognition.