Note 2. Revenue

The Company has entered into license agreements and collaborative research and development arrangements with pharmaceutical and biotechnology companies, as well as consulting, related technology transfer, product revenue and government grant agreements. Under these arrangements, the Company is entitled to receive license fees, consulting fees, product fees, technological transfer fees, upfront payments, milestone payments if and when certain research and development milestones, technology transfer milestones or success-based milestones are achieved, royalties on approved product sales and reimbursement for research and development activities. The Company’s costs of performing these services are included within research and development expenses. The Company’s milestone payments are typically defined by achievement of certain preclinical, clinical, and commercial success criteria. Preclinical milestones may include in vivo proof of concept in disease animal models, lead candidate identification, and completion of IND-enabling toxicology studies. Clinical milestones may, for example, include successful enrollment of the first patient in or completion of Phase 1, 2 and 3 clinical trials, and commercial milestones are often tiered based on net or aggregate sale amounts. The Company cannot guarantee the achievement of these milestones due to risks associated with preclinical and clinical activities required for development of nucleic acid medicine-based therapeutics and vaccines.

The following paragraphs provide information regarding the nature and purpose of the Company’s most significant collaboration and grant arrangements.

CSL Seqirus

On November 1, 2022, the Company entered into a Collaboration and License Agreement (as amended, the “CSL Collaboration Agreement”) with Seqirus, Inc., a part of CSL Limited (“CSL Seqirus”), for the global exclusive rights to research, develop, manufacture, and commercialize vaccines. Under the terms of the CSL Collaboration Agreement, the Company provides CSL Seqirus with an exclusive global license to its mRNA technology (including STARR®) and LUNAR® lipid-mediated delivery, along with mRNA drug substance and drug product manufacturing processes. CSL Seqirus will lead the development and commercialization of vaccines under the collaboration. In September 2024, our COVID-19 vaccine KOSTAIVE® became the world’s first approved and commercially available self-amplifying RNA (sa-mRNA) vaccine.

The Company received a $200.0 million upfront payment under the arrangement.

In evaluating the CSL Collaboration Agreement in accordance with ASC 606, the Company concluded that CSL Seqirus is a customer. The Company identified all promised goods/services within the CSL Collaboration Agreement, and when combining certain promised goods/services, the Company concluded that there are five distinct performance obligations.

As of June 30, 2026, the transaction price consisted of upfront consideration received and milestones achieved. Additional variable consideration was not included in the transaction price as of June 30, 2026, because the Company could not conclude that it is probable that including the variable consideration will not result in a significant revenue reversal.

The Company allocated the transaction price to the performance obligations in proportion to their standalone selling price. The vaccine license was recognized at the point in time it was transferred in 2022. The research and development and regulatory activities performance obligations are recognized over a period of time based on the percentage of services rendered using the input method, meaning actual costs incurred divided by total costs budgeted to satisfy the performance obligation. Any consideration related to sales-based royalties will be recognized when the amounts are probable of non-reversal, provided that the reported sales are reliably measurable and the Company has no remaining promised goods/services, as they are constrained and therefore have also been excluded from the transaction price. The revenue recognized during the six months ended June 30, 2026 relates to services performed through June 30, 2026.

Total deferred revenue as of June 30, 2026 and December 31, 2025 for the CSL Collaboration Agreement was $5.2 million and $6.2 million, respectively.

During 2023, the Company entered into an amendment to the CSL Collaboration Agreement, pursuant to which the Company agreed to sponsor and conduct a Phase 1 clinical study in the influenza field. As part of the amendment, the Company received $17.5 million from CSL Seqirus. The Company previously concluded that the expansion of research and development support services under the CSL Collaboration Agreement represented an option that was not a material right. Therefore, the Company concluded the promise to sponsor and conduct the Phase 1 clinical study is a separate contract and the sole performance obligation under the new arrangement. The performance obligation was fully satisfied during the 2025 period.

In March 2024, the Company entered into an amendment to the CSL Collaboration Agreement, pursuant to which the parties agreed to, among other things, adjust (i) the development plans for certain product candidates, (ii) various development milestones related to such product candidates, (iii) provisions of the CSL Collaboration Agreement related to specific royalty payments, (iv) provisions of the CSL Collaboration Agreement related to distributors, and (v) proprietary payment calculations related to the foregoing.

As of June 30, 2026, the Company and CSL Seqirus were in discussions regarding termination of the CSL Collaboration Agreement and had reached an understanding on the principal commercial terms; however, the CSL Collaboration Agreement had not been terminated as of June 30, 2026. Accordingly, the Company continued to account for the CSL Collaboration Agreement in accordance with its existing terms through June 30, 2026. On August 3, 2026, the Company entered into a Termination and Settlement Agreement (the “Termination Agreement”) with CSL Seqirus. See “Note 11 Subsequent Events” for additional information.

BARDA

In August 2022, the Company entered into a cost reimbursement contract (the “BARDA Contract”) with the Biomedical Advanced Research and Development Authority ("BARDA"), a division of the Office of the Assistant Secretary for Preparedness and Response (ASPR) within the U.S. Department of Health and Human Services (HHS) for an award of up to $63.2 million for the development of a pandemic influenza vaccine using the Company's STARR® self-amplifying mRNA vaccine platform technology. The Company earns grant revenue for performing tasks under the agreement.

The Company determined that the BARDA Contract is not in the scope of ASC 808 or ASC 606. Applying International Accounting Standards No. 20 ("IAS 20"), Accounting for Government Grants and Disclosure of Government Assistance, by analogy, the Company recognizes grant revenue from the reimbursement of direct out-of-pocket expenses, overhead allocations and fringe benefits for research costs associated with the grant. The costs associated with these reimbursements are reflected as a component of research and development expense in the Company’s condensed consolidated statements of operations and comprehensive loss.

As of June 30, 2026, the remaining available funding net of revenue earned was $24.6 million.

Gates Foundation

The Company recognized grant revenue related to cost reimbursement under two grants awarded by the Gates Foundation.

The grants support development of (i) a therapeutic HPV vaccine candidate and (ii) durability assessments of self-amplifying mRNA COVID-19 vaccine platforms. Grant funding is conditional upon achievement of defined milestones and submission of periodic progress and financial reports. Revenue is recognized when qualifying costs, including employee full-time equivalent (“FTE”) labor and related expenses, are incurred in accordance with the terms of each agreement.

Unspent or uncommitted amounts remain deferred until the associated performance obligations are satisfied. As of June 30, 2026, deferred grant revenue related to these agreements totaled $1.1 million.