Obsidian Therapeutics to Present Clinical Data from OBX-115, its Engineered TIL Cell Therapy, for Patients with Advanced Melanoma in Oral Presentation at the 2025 ASCO Annual Meeting

• Oral presentation of Phase 1 results from Agni-01 multicenter study of OBX-115, a novel, IL2-sparing engineered TIL cell therapy armored with pharmacologically regulatable membrane-bound IL15 (mbIL15), in patients with ICI-resistant advanced melanoma
• Additional poster presentation summarizing translational data from Phase 1 first-in-human single-center study of OBX-115 (enrollment completed) in ICI-resistant advanced melanoma

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Obsidian Therapeutics, Inc., a clinical-stage biotechnology company pioneering engineered cell and gene therapies, today announced two presentations, including an oral presentation on the Phase 1/2 Agni-01 multicenter study of OBX-115, a novel engineered tumor-derived autologous T cell immunotherapy (tumor-infiltrating lymphocyte [TIL] cell therapy) armored with pharmacologically regulatable membrane-bound IL15 (mbIL15), in patients with immune checkpoint inhibitor (ICI)-resistant advanced or metastatic melanoma (NCT06060613), at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place in Chicago on May 30–June 3.

Oral Presentation:

• Title: OBX-115 engineered tumor-infiltrating lymphocyte (TIL) cell therapy with regulatable membrane-bound IL15 (mbIL15) in patients (pts) with immune checkpoint inhibitor (ICI)-resistant advanced melanoma: Phase 1 results of the Agni-01 multicenter study
• Session Title: Rapid Oral Abstract – Melanoma/Skin Cancers
• Date and Time: Monday, June 2, at 9:45 a.m. CT/10:45 a.m. ET
• Abstract Number: 9517
• Speaker/Lead Author: Jason A. Chesney, UofL Health – Brown Cancer Center, Louisville, KY
• Clinical Trial Identifier: NCT06060613 (Multicenter study)

Poster Presentation:

• Title: OBX-115 engineered tumor-infiltrating lymphocytes (TIL) with regulatable membrane-bound IL15 (mbIL15): Translational data from a single-center phase 1 trial in patients (pts) with immune checkpoint inhibitor (ICI)-resistant advanced melanoma.
• Session Title: Poster Session – Melanoma/Skin Cancers
• Date and Time: Sunday, June 1, at 9:00 a.m. CT/10:00 a.m. ET
• Abstract Number: 9519
• Speaker/Lead Author: Rodabe N. Amaria, The University of Texas MD Anderson Cancer Center

About OBX-115
Obsidian’s lead investigational cytoTIL15™ program, OBX-115, is a novel engineered tumor-derived autologous T cell immunotherapy (tumor-infiltrating lymphocyte [TIL] cell therapy) armored with pharmacologically regulatable membrane-bound IL15 (mbIL15). OBX-115 has the potential to become a meaningful therapeutic option for patients with advanced or metastatic melanoma and other solid tumors by leveraging the expected benefits of mbIL15 and Obsidian’s proprietary, differentiated manufacturing process to enhance persistence, antitumor activity, and clinical safety of TIL cell therapy. Obsidian is investigating OBX-115 in the phase 1/2 Agni-01 multicenter trial in patients with advanced solid tumors (NCT06060613).

About Obsidian Therapeutics
Obsidian Therapeutics, Inc. is a clinical-stage biotechnology company pioneering engineered cell and gene therapies to deliver transformative outcomes for patients with intractable diseases. Obsidian’s proprietary cytoDRiVE^® technology is designed to precisely regulate the timing and level of protein function by using FDA-approved small-molecule drugs. Obsidian is headquartered in Cambridge, MA. For more information, please visit www.obsidiantx.com and follow us on LinkedIn.