51³Ô¹ÏPro

April 24, 2024

51³Ô¹ÏPro to Present Clinical Data from OBX-115, its Engineered TIL Cell Therapy, for Patients with Advanced Solid Tumors in Oral Presentation at the 2024 ASCO Annual Meeting

• Oral presentation of preliminary results from Phase 1 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 advanced or metastatic melanoma
• Additional trial-in-progress poster presentation outlining the details of the ongoing Phase 1/2 trial of OBX-115 in patients with advanced solid tumors

CAMBRIDGE, Mass., April 24, 2024 –Ìý51³Ô¹ÏPro.,Ìýa clinical-stage biotechnology company pioneering engineered cell and gene therapies, today announced two presentations, including an oral presentation on the Phase 1 first-in-human 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 (), at the 2024 American Society of Clinical Oncology (ASCO) Annual Meeting, taking place in Chicago on May 31–June 4.

Oral Poster Presentation

• Title:ÌýOBX-115, an interleukin 2 (IL2)-sparing engineered tumor-infiltrating lymphocyte (TIL) cell therapy, in patients (pts) with immune checkpoint inhibitor (ICI)-resistant unresectable or metastatic melanoma.
• Session Title:ÌýRapid Oral Abstract – Melanoma/Skin Cancers
• Date and Time:ÌýMonday, June 3, atÌý9:45 a.m. CT/10:45 a.m. ET
• Abstract Number: 9515
• Speaker/Lead Author:ÌýRodabe N Amaria, M.D., The University of Texas MD Anderson Cancer Center
• Clinical Trial Identifier: (First-in-human study)

Trials in Progress Poster Presentation

• Title:ÌýA phase 1/2 study to investigate the safety and efficacy of OBX-115 engineered tumor-infiltrating lymphocyte (TIL) cell therapy in patients (pts) with advanced solid tumors.
• Session Title:ÌýPoster Session – Melanoma/Skin Cancers
• Date and Time:ÌýSaturday, June 1, atÌý1:30 p.m. CT/2:30 p.m. ET
• Abstract Number: TPS9599
• Speaker/Lead Author:ÌýAdam J Schoenfeld, M.D., Memorial Sloan Kettering Cancer Center
• Clinical Trial Identifier: (Multicenter study)

About OBX-115

Obsidian’s lead investigational cytoTIL15â„¢ 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. OBX-115 is being investigated in two ongoing and enrolling clinical trials in advanced or metastatic melanoma and NSCLC (andÌý).

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About 51³Ô¹ÏPro

51³Ô¹ÏPro. 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. The Company has collaborations with Bristol Myers Squibb and Vertex Pharmaceuticals. For more information, please visit and follow us on LinkedIn.

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