Note 5. Collaboration and License Agreements

Collaboration and License Agreement with Boehringer Ingelheim International GmbH

In October 2022, the Company executed a Collaboration and License Agreement, or the CLA, with Boehringer Ingelheim International GmbH, or Boehringer Ingelheim, to research, develop and commercialize Frizzled 4, or Fzd4, bi-specific antibodies designed using the Company’s SWAP technology, including SZN-413. Boehringer Ingelheim and the Company conducted partnership research focused on SZN-413 during a 1.5-year period. The Company granted Boehringer Ingelheim an exclusive, royalty-bearing, worldwide, sublicensable license, under the applicable patents and know-how, to develop, manufacture and commercialize, for all uses, one lead and two back-up Fzd4 bi-specific antibodies selected by Boehringer Ingelheim. After an initial period of joint research, Boehringer Ingelheim is responsible for all further research, preclinical and clinical development, manufacturing, regulatory approvals, and commercialization of licensed products at its expense. Unless terminated earlier, the CLA will remain effective, on a country-by-country and product-by-product basis, until the expiration of Boehringer Ingelheim’s royalty obligations. Boehringer Ingelheim has the right to terminate the CLA for any reason after a specified notice period. Each party has the right to terminate the CLA on account of the other party’s bankruptcy or material, uncured breach.

Under the terms of the CLA, Boehringer Ingelheim agreed to pay a non-refundable upfront payment of $12.5 million less any applicable withholding tax, success-based milestone payments up to a total of $587.0 million and mid-single digit to low-double digit royalties on net sales of the licensed products should any reach commercialization. The royalty payments will be subject to reduction due to patent expiration, generic competition and payments made under certain licenses for third-party intellectual property. In March 2026, Boehringer Ingelheim achieved a research milestone, reflecting a positive outcome of the IND-enabling GLP toxicology study. The achievement of the research milestone entitled the Company to receive a $5.0 million non-refundable and non-creditable payment from Boehringer Ingelheim. The Company recognized such amount as collaboration and license revenue for the three months ended March 31, 2026 and accounts receivable as of March 31, 2026. The milestone payment of $5.0 million was received in April 2026.

The Company determined that the CLA is within the scope of ASC 606. The Company evaluated the promised goods and services and determined that the license to the Company’s intellectual property granted to Boehringer Ingelheim represented one performance obligation for the purposes of conducting the partnership research and further development on SZN-413. The transaction price was determined to be the non-refundable upfront payment at the inception. Variable consideration related to future milestones is fully constrained because the Company cannot conclude that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur, given the inherent uncertainty of success with these future milestones. For sales-based royalties, the Company determined that the license is the predominant item to which the royalties relate to. Accordingly, the Company will recognize revenue

at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all the royalty has been allocated has been satisfied (or partially satisfied). The Company will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur.