GlobeNewswire Inc | May 11, 2021 07:30AM EDT

May 11, 2021

NEW YORK, May 11, 2021 (GLOBE NEWSWIRE) -- SELLAS Life Sciences Group, Inc. (Nasdaq: SLS) ("SELLAS" or the Company), a late-stage clinical biopharmaceutical company focused on developing novel cancer immunotherapies for a broad range of indications, today announced that it will host a Shareholder Update Call on Thursday, June 3, 2021 at 8:30 a.m. ET.

The call will be facilitated by SELLAS President & CEO, Angelos Stergiou, MD, ScD. h.c., who will provide a corporate update.

Event: Shareholder Update CallDate: Thursday, June 3, 2021Time: 8:30 a.m. ETLive Call: 1-877-407-9716 (U.S. Toll Free) or 1-201-493-6779 (International)Webcast: https://www.sellaslifesciences.com/investors/ events-and-presentations

For interested individuals unable to join the conference call, a replay of the call will be available through June 17, 2021, at 1-844-512-2921 (U.S. Toll Free) or 1-412-317-6671 (International). Participants must use the following code to access the replay of the call: 13719788. The online archive of the webcast will be available at https://www.sellaslifesciences.com/investors/events-and-presentations after the conclusion of the call.

About SELLAS Life Sciences Group, Inc. SELLAS is a late-stage clinical biopharmaceutical company focused on developing novel cancer immunotherapeutics for a broad range of 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 potential both as a monotherapy and in combination to address a broad spectrum of hematologic malignancies and solid tumor indications. SELLAS second product candidate, nelipepimut-S (NPS), is a HER2-directed cancer immunotherapy with potential to treat patients with early-stage breast cancer with low to intermediate HER2 expression, otherwise known as HER2 1+ or 2+, which includes TNBC patients, following the standard of care.

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 Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of various important factors. 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.

For more information, please contact:

Investor Contacts Valter Pinto / Allison Soss KCSA Strategic Communications Email:SELLAS@kcsa.com Phone: 914.907.2675 / 215.272.2707

Media Contacts Caitlin Kasunich / Raquel Cona KCSA Strategic Communications Email:SELLAS@kcsa.com Phone: 212.896.1241 / 212.896.1276