Protagonist Therapeutics Inc 2025年度报告

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during thepreceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past90 days.Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerginggrowth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of theExchange Act. Large Accelerated Filer☒Non-Accelerated Filer☐ Accelerated FilerSmaller Reporting CompanyEmerging Growth Company If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revisedfinancial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.☒If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflectthe correction of an error to previously issued financial statements.☐ Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any ofthe registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b).☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act of 1934).Yes☐No☒ The aggregate market value of the voting and non-voting common equity held by non-affiliates of the registrant was approximately $2.9 billion as of June 30, 2025,based upon the closing sale price on The Nasdaq Stock Market LLC reported on June 30, 2025. Excludes an aggregate of 9,532,421 shares of the registrant’s common stockheld by officers, directors and affiliated stockholders. For purposes of determining whether a stockholder was an affiliate of the registrant at June 30, 2025, the registrantassumed that a stockholder was an affiliate of the registrant if such stockholder (i) beneficially owned 10% or more of the registrant’s common stock, as determined basedon public filings and/or (ii) was an executive officer or director or was affiliated with an executive officer or director of the registrant. Exclusion of such shares should not beconstrued to indicate that any such person possesses the power, direct or indirect, to direct or cause the direction of the management or policies of the registrant or that suchperson is controlled by or under common control with the registrant. There were 63,808,716 shares of registrant’s Common Stock, par value $0.00001 per share, outstanding as of February 18, 2026. DOCUMENTS INCORPORATED BY REFERENCE: Portions of the registrant’s definitive Proxy Statement for the registrant’s 2026 Annual Meeting of Stockholders are incorporated by reference into Part III of this report.Such proxy statement will be filed with the Securities and Exchange Commission within 120 days after the end of the registrant’s fiscal year ended December 31, 2025. PROTAGONIST THERAPEUTICS, INC.2025 FORM 10-K ANNUAL REPORTTABLE OF CONTENTS Item 1.Business. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4Item 1A.Risk Factors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30Item 1B.Unresolved Staff Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Item 1C.Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57Item 2.Properties. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .58Item 3.Legal Proceedings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5