Secarna Pharmaceuticals GmbH & Co. KG, a company focused on redefining the discovery and development of best-in-class oligonucleotide therapeutics, will present new pre-clinical data on its lead program, SECN-15. This potential first-in-class antisense oligonucleotide (ASO) targets the transmembrane protein Neuropilin 1 (NRP1) and will be showcased at the American Association for Cancer Research (AACR) 2025 Annual Meeting, taking place from April 25 – 30 in Chicago, Illinois, USA. The data presented will demonstrate SECN-15’s ability to modulate the tumor microenvironment and its potential to significantly enhance the efficacy of immune checkpoint inhibitors (ICIs), especially in solid tumors.

The following poster will be presented:

Title: Neuropilin-1 specific antisense oligonucleotides exhibit anti-tumor activity in vivo and significantly increase the efficacy of checkpoint inhibitors

Poster number: 9

Poster Session: Overcoming Checkpoint Inhibition and Tumor Suppression, April 30, 9:00 am – 12:00 pm

Presenter: Richard Klar, PhD, Chief Research Officer

NRP1 is expressed on various cell types in the tumor microenvironment, where it exerts immunosuppressive and protumorigenic effects through interactions with multiple receptors and ligands. Overexpression of NRP1 is linked to poor prognosis in cancers like gastric cancer, breast cancer, and glioblastoma.

Dr. Richard Klar, Chief Research Officer at Secarna Pharmaceuticals, commented, “We are excited to present the latest findings from our lead oncology program SECN-15, an ASO targeting NRP1, at AACR. The data show that SECN-15 has the potential to strongly enhance the therapeutic impact of immune checkpoint inhibitors. This innovative approach could lead to more effective treatment options for patients with solid tumors, including gastric cancer, where checkpoint inhibitors have shown limited efficacy. We are preparing for first-in-human trials to further explore this promising therapeutic combination strategy.”

Key findings from the research highlight the efficacy of SECN-15. Secarna used its proprietary, AI-driven oligonucleotide platform, OligoCreatorTM, to design and characterize highly active and safe NRP1-specific locked nucleic acid (LNA)-modified ASOs. The presented data demonstrate that SECN-15 effectively knocks down NRP1 in key immune cell types, such as T cells and macrophages, both in vitro and in vivo. This downregulation leads to increased T cell activation and remodeling of the extracellular matrix in tumors.

In animal models, treatment with NRP1-specific ASOs resulted in delayed tumor growth and, in some cases, complete tumor eradication. These ASOs also strongly enhanced the efficacy of ICIs. Notably, mice that achieved complete responses in both monotherapy and combination therapy settings showed rapid tumor eradication upon tumor re-challenge, suggesting the induction of an anti-tumor memory immune response.

Based on these translational research findings, gastric cancer—where ICI monotherapy has shown limited activity—has been selected as one of the lead indications for the planned Phase I/II clinical trials. Secarna is currently conducting pre-IND studies with SECN-15, and a Phase I/II clinical trial is scheduled to begin in mid-2026.

Source: https://www.secarna.com/news-events/news/secarna-pharmaceuticals-to-present-positive-new-data-on-antisense-oligonucleotide-secn-15-targeting-nrp1-as-monotherapy-and-in-combination-with-immune-checkpoint-inhibitors-at-aacr-2