• SECN-15 represents promising new therapeutic strategy to enhance anti-tumor immunity and overcome resistance to checkpoint inhibitors
• Preclinical data demonstrate strong anti-tumor efficacy in monotherapy as well as in combination therapy setting
• Translational data confirm gastric cancer as one of the lead indications for planned clinical Phase I/II trial

Martinsried (Munich), Germany, November 4, 2025 - Secarna Pharmaceuticals GmbH & Co. KG, a company redefining the discovery and development of best-in-class oligonucleotide therapeutics today announced that preclinical data for its proprietary antisense oligonucleotide (ASO) SECN-15 will be presented in a poster session at the 40th Anniversary Annual Meeting of the Society for Immunotherapy of Cancer (SITC) in National Harbor, MD, USA, on Friday, November 7, 2025.

Poster Highlights
The poster outlines the potential of SECN-15 as a high-affinity ASO designed to selectively downregulate Neuropilin-1 (NRP1) expression, a promising target in oncology with the potential to break resistance to immune checkpoint inhibitors (ICIs). Elevated NRP1 expression correlates with poor prognosis across multiple solid tumors and is associated with epithelial-mesenchymal transition (EMT), angiogenesis, fibrosis and the establishment of an immunosuppressive tumor microenvironment – key processes that drive tumor progression and resistance to currently approved immunotherapies.
SECN-15 demonstrates strong anti-tumor efficacy both as monotherapy and in combination with ICIs in mouse tumor models, where ICIs only show limited efficacy. Gastric cancer, a tumor type in which high NRP1 expression is linked to inferior outcomes, has been identified as a potential lead indication for a planned clinical Phase I/II trial. IND-enabling studies are currently underway to advance SECN-15 into clinical development.

“We are delighted to present preclinical and new translational data from our lead program SECN-15 in a poster presentation at the SITC 2025 Annual Meeting,” said Richard Klar, PhD, Chief Research Officer of Secarna Pharmaceuticals. “These encouraging findings provide the right impetus to advance SECN-15 into clinical development, and our team is in preparations for the first-in-human clinical trials to be initiated.”

Poster Presentation Details
Title: SECN-15: Targeting Neuropilin-1 with Antisense Oligonucleotides Overcomes Checkpoint Inhibitor Resistance in Solid Tumors
Presenting Author: Richard Klar, PhD, Chief Research Officer, Secarna Pharmaceuticals
Abstract Number: 659
Primary Category: Combination Immunotherapies
Poster Session: November 7, 2025

About Secarna Pharmaceuticals

Secarna Pharmaceuticals is a biopharmaceutical company redefining the discovery and development of best-in-class oligonucleotide therapeutics, offering hope to patients facing conditions that are beyond the reach of current approaches and modalities. With the Company’s proprietary AI-empowered OligoCreator® platform, which includes multiple delivery technologies, Secarna identifies and characterizes oligonucleotide therapeutics with unparalleled speed and excellent safety and efficacy. By delivering these novel therapeutics to the cells, organs, or tissues where they are needed, targeted oligonucleotide therapies have the potential to revolutionize treatments for a wide range of difficult-to-treat disorders. Secarna’s unique OligoCreator® platform is leveraged to transform untreatable conditions into treatable ones, profoundly changing the future of medicine. www.secarna.com