10. DRL Development Agreement

In 2023, the Company entered into a Development and License Agreement (the “DRL Development Agreement”) with DRL and its affiliate, Dr. Reddy's Laboratories SA (collectively, "Dr. Reddy's") , pursuant to which, among other things, the Company granted to Dr. Reddy's an exclusive, royalty-bearing right and license (the "License") to commercialize COYA 302, a proprietary co-pack kit containing low dose IL-2 and CTLA4-Ig, (“COYA 302” or the “Product”) solely for use in patients with amyotrophic lateral sclerosis (“ALS" or the “Field”) in the United States, Canada, the European Union and the United Kingdom (collectively, the “New Territories”). The Company previously granted DRL an exclusive license to obtain regulatory approval and commercialize the Product for ALS and certain other indications in all other countries (other than the New Territories, Japan, Mexico, and in each country in South America), pursuant to the DRL Agreement entered between the Company and DRL, effective as of April 1, 2023 (Note 6). As part of the DRL Development Agreement, the Company is responsible for certain development activities to advance the Product through clinical development ("R&D Services").

In June 2024, the Company entered into the First Amendment to the DRL Development Agreement (the "First Amendment"), with Dr. Reddy's, pursuant to which, among other things, Dr. Reddy's paid the Company a one-time payment of $3.9 million and, in return, Dr. Reddy's will have no obligation to pay the first $6.0 million in royalty payments that would have otherwise been payable to the Company under the DRL Development Agreement.

The collaboration is managed by a joint steering committee (“JSC”) which is comprised of representatives from both parties. Decisions of the JSC are made by consensus. If the JSC is unable to reach a consensus, and the parties’ executives are not able to resolve the dispute, then Dr. Reddy’s has final decision-making authority, subject to specified limitations (as set forth in the DRL Development Agreement).

Pursuant to the DRL Development Agreement, the Company received an up-front, nonrefundable payment of $7.5 million in January 2024. Additionally, in August and December 2025, the Company received an aggregate of $8.4 million as a result of the ALS IND Milestone and the Dosing Milestone. The DRL Development Agreement also calls for up to an aggregate of approximately $40.0 million in development milestones and up to an aggregate of approximately $677.3 million in sales milestones, related to the New Territories, should all such development and sales milestones be achieved. The Company will also be owed royalties by Dr. Reddy's on Net Sales (as defined in the DRL Development Agreement) of the Product in the low to mid-teens. Pursuant to the First Amendment, as discussed above, the first $6.0 million of royalty payments will not be owed to the Company.

Both parties shall discuss in good faith and agree in writing on the terms of a commercial supply agreement for the purpose of supply of COYA 302 to Dr. Reddy’s. No such agreement has been entered into at the time of the filing of this Annual Report on Form 10-K.

The DRL Development Agreement expires on a country-by-country basis upon expiration of Dr. Reddy's obligation to make royalty payments for Product in each territory. Dr. Reddy's has the right to terminate the agreement upon specified prior written notice to the Company. Additionally, either party may terminate the agreement in the event of an uncured material breach of the agreement by, or insolvency of, the other party. Either party may terminate the agreement in the event that the other party commences a legal action challenging the validity, enforceability or scope of any licensed patent rights.

In accordance with the guidance, the Company identified the following commitments under the arrangement: 1) the License and 2) the R&D Services. The Company determined that these two commitments represent distinct performance obligations for purposes of recognizing revenue as the Company fulfills these performance obligations. The Company included the $7.5 million upfront payment in the transaction price as of the outset of the arrangement and allocated that transaction price to the two performance obligations based on the estimated stand-alone selling prices at contract inception. The stand-alone selling price of the License was based on a discounted cash flow approach and considered several factors including, but not limited to, discount rate, development timeline, regulatory risks, estimated market demand and future revenue potential using an adjusted market approach. The stand-alone selling price of the R&D Services was estimated using the expected cost-plus margin approach. In connection with the First Amendment, ALS IND Milestone, and Dosing Milestone the transaction price was increased by the $3.9 million, $4.2 million, and $4.2 million respectively, payments received, which did not add any additional performance obligations. As such, the Company allocated the increase in transaction price to the License and R&D Services performance obligation in the same manner as was performed at contract inception using the estimated standalone selling price. The Company recognized the License portion of the transaction price upon delivery of the License in December 2023, then again in June 2024, August 2025, and in December 2025 as a cumulative catch-up adjustments in connection with the First Amendment, ALS IND Milestone and Dosing Milestone, respectively. The Company will continue to recognize the remaining transaction price of $4.0 million allocated to the R&D Services over the period of performance, using an inputs approach.

During the year ended December 31, 2025, the Company recognized $0.5 million of collaboration revenue associated with the performance of R&D Services which was included in deferred revenue as of December 31, 2024. Any portion of a change in transaction price that is allocated to a satisfied or partially satisfied performance obligation will be recognized as revenue (or as a reduction in revenue) in the period of the transaction price change on a cumulative catch-up basis. The commercial milestones and sales-based royalties are recognized when earned (i.e., the later of when the subsequent sales occur or the performance obligation has been satisfied).

As of December 31, 2025, $2.2 million of the payments received from Dr. Reddy's was recorded in deferred revenue in the accompanying balance sheets, related to R&D Services yet to be provided, of which $1.2 million is estimated to be recognized within one year. R&D Services revenue is calculated quarterly using the inputs approach, by applying actual COYA 302 expenses against budgeted COYA 302 expenses as the inputs. Budgeted spending for COYA 302 includes total forecasted pre-clinical and clinical costs, associated with the advancement of COYA 302 for the treatment of patients with ALS, necessary to satisfy the R&D Services performance obligation. R&D Services and License revenue were $1.2 million and $6.7 million, respectively, during the year ended December 31, 2025. R&D Services and License revenue were $0.5 million and $3.1 million, respectively, during the year ended December 31, 2024.