SEELAS Life Sciences Group Inc 2025年度报告

TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 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 the preceding12 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 past 90 days. YesxNoo 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 emerging growthcompany. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act. 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 revised financialaccounting standards provided pursuant to Section 13(a) of the Exchange Act.o Table of Contents 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 financialreporting 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 theAct, indicate by check mark whether the financial statements of the registrant included in the filing reflect thecorrection 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 of theregistrant’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 ExchangeAct).☐Yes xNo The aggregate market value of the registrant's common stock, $0.0001 per value per share, held by non-affiliates of the registrant on June 30, 2025, the last business day ofthe registrant's most recently completed second fiscal quarter, was $219,132,515 (based on the closing sales price of the registrant's common stock on that date). Shares ofthe registrant's common stock held by each officer and director and each person who owns 5% or more of the outstanding common stock of the registrant have beenexcluded in that such persons may be deemed to be affiliates. This determination of affiliate status is not necessarily a conclusive determination for other purposes. As ofMarch 18, 2026, SELLAS Life Sciences Group, Inc. had outstanding 179,582,574 shares of common stock, $0.0001 par value per share, exclusive of treasury shares. DOCUMENTS INCORPORATED BY REFERENCE Certain information required in Part III of thisAnnual Report on Form 10-K is incorporated from the registrant’s Proxy Statement for its 2026 Annual Meeting of Stockholdersto be filed with the Securities and Exchange Commission pursuant to Regulation 14A not later than 120 days after the end of the fiscal year covered by this Form 10-K,provided that if such Proxy Statement is not filed within such period, such information will be included in an amendment to this Form 10-K to be filed within such 120-dayperiod. SPECIAL NOTE REGARDING FORWARD LOOKING STATEMENTS This Annual Report on Form 10-K includes forward-looking statements that reflect our current views with respect to our development programs, businessstrategy, business plan, financial performance and other future events. These statements include forward-looking statements both with respect to us,specifically, and our industry, in general. Such forward-looking statements include the words "expect," "intend,” "plan," "believe," "project," "estimate,” "may,”"should," "anticipate," "will" and similar statements of a future or forward-looking nature identify forward-looking statements and include, without limitation,statements regarding: •our future financial and business performance;•strategic plans for our business and product candidates;•our ability to develop or commercialize products;•the expected results and timing of clinical trials and nonclinical studies;•our ability to comply with the terms of our license agreements;•developments and projections relating to our competitors and industry;•our expectations regarding our ability to obtain, develop and maintain intellectual property protection and not infringe on the rights of others;•our ability to retain and attract highly-skilled executive officers and employees;•our future capital requirements and the timing of those requirements and sources and uses of cash;•our ability to obtain funding for our operations; and•changes in applicable laws or regulations. These statements are subject to known and unknown risks, uncertainties and assumptions that could ca