NEW YORK, Jan. 03, 2024 (GLOBE NEWSWIRE) — SELLAS Life Sciences Group, Inc. (NASDAQ: SLS) (“SELLAS” or the “Company”), a late-stage clinical biopharmaceutical company focused on developing novel therapies for a broad range of cancer indications, today announced that it intends to offer and sell shares of its common stock (or common stock equivalents in lieu thereof) and warrants to purchase shares of common stock in a public offering. All of the securities to be sold in the offering are to be offered by SELLAS. The Company intends to use the net proceeds from the offering for funding of ongoing operations, including clinical development of existing product candidates, and for working capital and other general corporate purposes. A.G.P./Alliance Global Partners is acting as sole placement agent for the offering on a best-efforts basis. The offering is subject to market conditions, and there can be no assurance as to whether or when the offering may be completed, or as to the actual size or terms of the offering. This offering is being made pursuant to an effective shelf registration statement on Form S-3 (File No. 333-255318) previously filed with the U.S. Securities and Exchange Commission (the “SEC”). The offering will be made only by means of a prospectus supplement and accompanying prospectus. The preliminary prospectus supplement and accompanying prospectus describing the terms of the proposed offering will be filed with the SEC and will be available on the SEC’s website located at http://www.sec.gov. Electronic copies of the preliminary prospectus supplement may be obtained, when available, from A.G.P./Alliance Global Partners, 590 Madison Avenue, 28th Floor, New York, NY 10022, or by telephone at (212) 624-2060, or by email at prospectus@allianceg.com. Before investing in this offering, interested parties should read in their entirety the prospectus supplement and the accompanying prospectus and the other documents that SELLAS has filed with the SEC that are incorporated by reference in such prospectus supplement and the accompanying prospectus, which provide more information about SELLAS and such offering. This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. About SELLAS Life Sciences Group, Inc. SELLAS is a late-stage clinical biopharmaceutical company focused on the development of novel therapeutics for a broad range of cancer indications. SELLAS’ lead product candidate, galinpepimut-S (GPS), is licensed from Memorial Sloan Kettering Cancer Center and targets the WT1 protein, which is present in an array of tumor types. GPS has the potential as a monotherapy and combination with other therapies to address a broad spectrum of hematologic malignancies and solid tumor indications. The Company is also developing SLS009 (formerly GFH009), a small molecule, highly selective CDK9 inhibitor, which is licensed from GenFleet Therapeutics (Shanghai), Inc., for all therapeutic and diagnostic uses in the world outside of Greater China. For more information on SELLAS, please visit www.sellaslifesciences.com. Forward-Looking Statements This press release contains forward-looking statements. All statements other than statements of historical facts are “forward-looking statements,” including those relating to future events. In some cases, forward-looking statements can be identified by terminology such as “plan,” “expect,” “anticipate,” “may,” “might,” “will,” “should,” “project,” “believe,” “estimate,” “predict,” “potential,” “intend,” or “continue” and other words or terms of similar meaning. These statements include, without limitation, statements about the Company’s expectations regarding the use of net proceeds of the proposed offering and other information that is not historical information. These forward-looking statements are based on current plans, objectives, estimates, expectations and intentions, and inherently involve significant risks and uncertainties. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of these risks and uncertainties, which include, without limitation, risks and uncertainties with oncology product development and clinical success thereof, the uncertainty of regulatory approval, and other risks and uncertainties affecting SELLAS and its development programs as set forth under the caption “Risk Factors” in SELLAS’ Annual Report on Form 10-K filed on March 16, 2023 and in its other SEC filings. Other risks and uncertainties of which SELLAS is not currently aware may also affect SELLAS’ forward-looking statements and may cause actual results and the timing of events to differ materially from those anticipated. The forward-looking statements herein are made only as of the date hereof. SELLAS undertakes no obligation to update or supplement any forward-looking statements to reflect actual results, new information, future events, changes in its expectations or other circumstances that exist after the date as of which the forward-looking statements were made. Investor Contact Bruce Mackle Managing Director LifeSci Advisors, LLC SELLAS@lifesciadvisors.com