Septerna, Inc. Revenue Disclosure

4. Collaboration and Research Service Agreements

For the year ended December 31, 2025, the Company's revenue is comprised solely of arrangements with Novo and Vertex. For the year ended December 31, 2024, the Company's revenue was solely comprised of the arrangement with Vertex.

Novo Collaboration Agreement

On May 13, 2025, the Company entered into a Collaboration and License Agreement with Novo (the “Novo Collaboration Agreement”). Under the Novo Collaboration Agreement, the Company and Novo are exclusively collaborating to leverage the Company’s proprietary Native Complex Platform™ to discover, develop and commercialize multiple potential oral small molecule therapies for metabolic-related diseases based on certain specified molecular targets.

Upon effectiveness of the Novo Collaboration Agreement on July 1, 2025, the Company and Novo have commenced four simultaneous research and development programs (each an “R&D Program”), each pursuing one or more Collaboration Targets (as defined in the Novo Collaboration Agreement) from discovery through development candidate selection. Subject to certain limitations, Novo also has a right to modify the research plan with the option to commence additional R&D Programs. Novo will reimburse the Company for 100% of the fully burdened costs arising from all research and development activities undertaken by the Company under the Novo Collaboration Agreement. After development candidate selection, beginning with investigational new drug-enabling activities, Novo will be responsible for all further global development and commercialization for each product candidate at its sole cost and expense unless the profit share option described below is exercised. Novo is also responsible for all commercialization costs subject to the Company’s profit share option for up to one program under the Novo Collaboration Agreement. Pursuant to the terms of the Novo Collaboration Agreement, the Company will provide Novo with exclusive licenses to enable Novo to develop and commercialize products directed at the Collaboration Targets. The Company retains all other rights to its Native Complex Platform™ and all of the Company’s other research and development programs.

Upon effectiveness of the Novo Collaboration Agreement, the Company received a one-time, non-refundable upfront payment of $195.0 million in July 2025, which was recorded as deferred revenue in its balance sheet. The Company is also eligible to receive up to approximately $498.0 million in research, development, regulatory, and commercial milestone payments for each R&D Program. In addition, the Company is entitled to escalating, tiered royalties ranging from mid to high single-digits based on global product sales on a country-by-country and product-by-product basis with respect to a R&D Program until the later of ten years after the date of first commercial sale of the first product in such R&D Program in such country, expiration of specified patent rights covering such product in such country or the expiration of specified regulatory exclusivity for the first product in such R&D Program in such country.

Under the Novo Collaboration Agreement, the Company has a one-time option to share in the global development costs and operating profits or losses (in lieu of milestones and royalties) with respect to one licensed product (the "Profit Share Option"), subject to certain terms, conditions and limitations. In the event that the Company chooses to exercise the Profit Share Option, it will be required to repay Novo all previously reimbursed developmental costs pertaining to that program at a predetermined multiple and reimburse Novo for a portion of the continued R&D costs incurred under the selected licensed product and will share in the profits resulting from the commercialization of the licensed product.

Unless earlier terminated, the term of the Novo Collaboration Agreement continues until expiration of the last royalty term for the applicable product in the applicable country. The Novo Collaboration Agreement is subject to customary termination provisions, including termination by a party for the other party’s uncured, material breach. The Novo Collaboration Agreement also includes customary representations and warranties, covenants and indemnification obligations.

The Company concluded the Agreement is not within the scope of Accounting Standards Codification 808, Collaborative Arrangements as the Company does not share equally in the exposure to significant risk. Accordingly, the Company assessed this arrangement in accordance with ASC 606 and concluded that the contract counterparty, Novo, is a customer.

At commencement, the Company identified the several performance obligations within the Novo Collaboration Agreement, including research and development services on research targets, option rights held by Novo, license to use the Company’s intellectual property to conduct research and development activities, and participation on the joint steering committee (“JSC”). At inception of the Novo Collaboration Agreement, the Company identified the following performance obligations:

The Company concluded that the license granted at contract inception is not distinct from the research services as the research services significantly modify the intellectual property underlying the license. As a result, for each R&D Program, the license has been combined with the research services and JSC participation into a single performance obligation, which is the combined performance obligation comprised of the license, related research services, and JSC participation.

In assessing whether the various options under the Novo Collaboration Agreement represent material rights, the Company considered the additional consideration the Company would be entitled to upon option exercise and the standalone selling price of the underlying goods and services. For the material right identified above, the Company concluded the option provided Novo with a discount that it otherwise would not have received.

The Company recognizes revenue related to the combined license and research services performance obligation and the manufacturing performance obligation over time using the input method. Under the input method, the extent of progress towards completion is measured based on the ratio of actual cost incurred to date to the total estimated cost at completion of the performance obligations, which the Company believes best measures its progress towards satisfying the performance obligations. A cost-based input method of revenue recognition requires management to make estimates of cost to complete the performance obligation. Judgment is required to evaluate assumptions related to cost estimates. The estimated standalone selling price for the material right was determined based on the estimated discount provided to Novo and the probability that Novo would exercise the option.

Amounts due to the Company for satisfying the revenue recognition criteria or that are contractually due based upon the terms of the Novo Collaboration Agreement are recorded as accounts receivable in the Company’s balance sheets. Contract liabilities consist of amounts received prior to satisfying the revenue recognition criteria, which are recorded as deferred revenue in the Company’s balance sheets.

The Company periodically assesses the probability of receiving payments from achieving the research and development, collaboration target, and regulatory milestones and includes the payment in the transaction price when they are deemed probable. Royalties and commercial sale milestones will be recognized when the subsequent sales occur based on the sales or usage-based royalty exception. The Company also periodically reassesses the probability of exercising Profit Share Option. As of December 31, 2025, none of the milestones were deemed probable and no royalty revenue has been recognized, and the Profit Share Option was deemed improbable with no amount recognized for repayment of reimbursements to Novo.

Vertex Asset Purchase and Research Service Agreement

Vertex Asset Purchase Agreement

In September 2023, the Company entered into an asset purchase agreement with Vertex, under which Vertex acquired an in-process research and development ("IPR&D") asset related to a GPCR program, including all intellectual property, materials, and compounds associated with the program (the “Vertex Asset Purchase Agreement”). The Vertex Asset Purchase Agreement also provided for a potential milestone payment payable to the Company contingent upon the achievement of a milestone event.

In July 2025, this milestone event was determined achieved and, as a result, the Company received a payment of $12.5 million in August 2025, which was recorded as a gain on sale of non-financial asset within total operating expenses in the Company’s statements of operations and comprehensive loss for the year ended December 31, 2025. The Company will not receive any other payments related to this IPR&D asset.

Vertex Research Service Agreement

In conjunction with the Vertex Asset Purchase Agreement in September 2023, the Company entered into research service agreement with Vertex under which the Company agreed to perform certain exploratory research activities for Vertex (the "Vertex Research Service Agreement"). The Company recognized service revenue associated with the Vertex Research Service Agreement over the performance period of the research services as the services were provided in accordance with ASC 606. The Vertex Research Service Agreement expired in September 2025.

During the year ended December 31, 2025, the Company recorded revenue of $0.6 million related to research activities performed in connection with the Vertex Research Service Agreement. During the year ended December 31, 2024, the Company recorded revenue of $1.1 million related to research activities performed in connection with the Vertex Research Service Agreement.