CAMBRIDGE, Mass., Nov. 9, 2021 – Obsidian Therapeutics, Inc., a biotechnology company pioneering engineered cell and gene therapies, today announced that the Company will present preclinical in vivo anti-tumor efficacy against melanoma data for its cytoTIL15™ program at the upcoming Annual Meeting of the Society for Immunotherapy of Cancer (SITC). The event will be hosted live in Washington, D.C. and virtually from November 10-14, 2021.
The abstract for the poster demonstrates enhanced in vivo potency of Obsidian’s cytoTIL15 product (TIL engineered with membrane-bound IL15) over conventional tumor-infiltrating lymphocytes (TILs) in PDX mouse models. The translation of previously observed in vitro and in vivo persistence of cytoTIL15 TILs, in the absence of IL2, to superior in vivo anti-tumor efficacy in PDX models supports the potential for increased efficacy of cytoTIL15 therapy over conventional TIL therapy in solid tumor malignancies. The abstract is also published in the Annual Meeting Abstract Book, in the Journal for ImmunoTherapy of Cancer (JITC)supplement and in the Poster Hall of the Conference location.
Title: Genetically engineered tumor-infiltrating lymphocytes (cytoTIL15) exhibit IL2-independent persistence and anti-tumor efficacy against melanoma in vivo
Abstract Number: 166
Category: Cellular Therapy
Adoptive cell therapy with tumor-infiltrating lymphocytes (TILs) has demonstrated tremendous promise in clinical trials for patients with solid tumors. However, current TIL therapy requires systemic administration of IL2 to promote TIL survival, and IL2-associated toxicities greatly limit patient eligibility and reduce the long-term clinical benefit of TIL therapy. Obsidian Therapeutics designed genetically engineered TILs to express a regulated form of membrane-bound IL15 for tunable long-term persistence, leading to enhanced persistence and efficacy in vitro and in PDX tumor models. cytoTIL15 TILs demonstrated enhanced potency over conventional TILs in vitro, and persisted without IL2 at greater frequencies compared to conventional TILs + IL2 in a 10-day antigen-independent in vitro assay. cytoTIL15 TILs adoptively transferred into naïve NSG mice demonstrated long-term persistence without antigen or exogenous IL-2, and importantly, cytoTIL15 TILs achieved significant tumor control in a human PDX model, which correlated with increased TIL accumulation in secondary lymphoid organs.
“We are pleased with the superior persistence, potency and anti-tumor activity of cytoTIL15 therapy in the absence of IL2,” commented Jan ter Meulen, M.D., Ph.D., Chief Scientific Officer of Obsidian. “These results highlight the clinical potential of cytoTIL15 TILs as a novel TIL product with enhanced safety and efficacy for patients with solid tumors.”
OBX-115 is Obsidian’s lead cytoTIL15 program, currently in preclinical development for the treatment of patients with metastatic melanoma and other solid tumors. OBX-115 is a novel engineered tumor infiltrating lymphocyte therapy engineered with regulated membrane-bound IL15 that does not require patients to receive concomitant IL2 therapy, a toxic and costly requirement for conventional TILs. The Company expects to submit an IND for OBX-115 in mid-2022.
About Obsidian Therapeutics
Obsidian Therapeutics, Inc. is a biotechnology company pioneering engineered cell and gene therapies to deliver transformative outcomes for patients with intractable diseases. Obsidian’s proprietary cytoDRiVE® technology provides a way to precisely control the timing and level of protein function by using FDA approved small molecules. Obsidian is headquartered in Cambridge, Mass. The Company has collaborations with Bristol Myers Squibb and Vertex Pharmaceuticals. For more information, please visit www.obsidiantx.com and follow us on LinkedIn and Twitter.
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