SELLAS Life Sciences to Present Preclinical Data on SLS009 in Pancreatic Ductal Adenocarcinoma at the 2026 AACR Conference on Pancreatic Cancer

- Three posters to highlight preclinical activity of SLS009 (tambiciclib) across patient-derived KRAS mutant organoid models of pancreatic cancer –

- Studies conducted in collaboration with the University of Wisconsin School of Medicine and Public Health -

NEW YORK, Sept. 02, 2026 (GLOBE NEWSWIRE) -- SELLAS Life Sciences Group, Inc. (NASDAQ: SLS) (“SELLAS’’ or the “Company”), a late-stage clinical biopharmaceutical company focused on the development of novel therapies for a broad range of cancer indications, today announced that three abstracts evaluating SLS009 (tambiciclib), a potent, selective CDK9 inhibitor, in preclinical models of pancreatic ductal adenocarcinoma (PDAC) have been accepted for poster presentation at the AACR Conference on Pancreatic Cancer: New Frontiers in Biology and Therapeutic Development. The conference will be held September 25–28, 2026, at the Hilton San Diego Bayfront in San Diego, CA.

"Pancreatic cancer remains one of the most difficult solid tumors to treat, with a significant need for new therapeutic approaches," said Angelos Stergiou, MD, ScD h.c., President and Chief Executive Officer of SELLAS. “The acceptance of three abstracts evaluating SLS009 across patient-derived organoid models reflects the breadth of our preclinical work in PDAC. We look forward to sharing these findings with the pancreatic cancer research community and discussing their potential implications for the further development of SLS009 in solid tumors."

Jeremy D. Kratz, MD, Assistant Professor of Medicine & Principal Investigator, University of Wisconsin-Madison commented: “These studies are designed to deepen our understanding of the mechanistic and translational rationale for CDK9 inhibition in pancreatic cancer. The presentations will explore the potential for SLS009 to create synthetic lethal interactions through rational combinations with BET- and KRAS-directed approaches, as well as its potential to exploit MYC-associated vulnerabilities. We look forward to sharing this work with the scientific community later this month.”

Poster presentation details: Title: Elucidating MYC allelic imbalance and therapeutic response in pancreatic ductal adenocarcinoma via patient-derived organoids Authors: Sawyer AG, Flannagan LE, Esguerra PN, Hossan MS, Kratz JD Poster Number: A036

Title: Synthetic Lethality Through Combined BET and CDK9 Inhibition in MYC-Amplified Pancreatic Ductal Adenocarcinoma Authors: Esguerra PN, Cadarso M, Livingwell S, Hossan MD, Wong O, Kratz JD Poster Number: B127

Title: Targeting dual CDK9 and KRASG12D selective inhibition as a novel combination therapy in pancreatic ductal adenocarcinoma Authors: Cadarso M, Esguerra P, Flannagan L, Hossan MS, Kratz JD Poster Number: B043

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, 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 (tambiciclib) - potentially the first and best-in-class differentiated small molecule CDK9 inhibitor with reduced toxicity and increased potency compared to other CDK9 inhibitors. Data suggests that SLS009 demonstrated a high response rate in AML patients with unfavorable prognostic factors including ASXL1 mutation, commonly associated with poor prognosis in various myeloid diseases. For more information on SELLAS, please visit www.sellaslifesciences.com.

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