Obsidian Therapeutics to Present Updated Amsoki-cel (OBX-115) Phase 1/2 Data in Advanced Melanoma at SITC 2026 Annual Meeting

Obsidian Therapeutics (OBX) will present updated amsoki-cel clinical trial data at the SITC annual meeting on November 7, 2026.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

CAMBRIDGE, Mass.--(BUSINESS WIRE)-- Obsidian Therapeutics, Inc. (“Obsidian”) (Nasdaq: OBX), a clinical-stage biopharmaceutical company harnessing novel protein-regulation technology to develop engineered tumor-infiltrating lymphocyte (TIL) cell therapies, today announced a poster presentation of updated data in patients with immune-checkpoint inhibitor (ICI)-resistant advanced melanoma from the Phase 1 single-center first-in-human (FIH) study and the Phase 1/2 Agni-01 multicenter study of amsokigene autoleucel (amsoki-cel, formerly OBX-115), an engineered TIL cell therapy armored with pharmacologically regulatable membrane-bound IL15 (mbIL15), at the Society for Immunotherapy of Cancer (SITC) 2026 Annual Meeting, taking place in Phoenix, AZ, November 4-8, 2026. The poster presentation will summarize pooled safety data across the FIH study and the Phase 1/2 Agni-01 multicenter study, and an efficacy update from Agni-01 patients treated at the recommended phase 2 dose (n=15).

In addition, a trial-in-progress poster describing the phase 2 registration-enabling cohort of Agni-01 evaluating amsoki-cel in patients with ICI-resistant advanced melanoma will be presented.

Poster Presentation Details:

• Title: OBX-115 TIL cell therapy in ICI-resistant advanced melanoma: Pooled safety and updated efficacy with minimally invasive tumor tissue procurement, low-dose lymphodepletion, and IL2-free regimen
• Session Title: Poster Session
• Abstract Number: 566
• Date: Saturday, November 7, 2026
• Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
• Lead Author: Rodabe N. Amaria, M.D., Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center
  
  

• Title: Trial in progress: Agni-01 phase 2 cohort of OBX-115 tumor-infiltrating lymphocyte (TIL) cell therapy in patients with advanced melanoma
• Session Title: Poster Session
• Abstract Number: 570
• Date: Saturday, November 7, 2026
• Location: PCC-North Building-Lower Level-Exhibition Halls 4-5-6
• Lead Author: Gino K. In, M.D., Division of Oncology, Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California

About Obsidian Therapeutics

Obsidian Therapeutics, Inc. is a clinical-stage biopharmaceutical company harnessing novel protein-regulation technology to develop engineered TIL cell therapies for the treatment of patients with solid tumors. 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 has offices in Cambridge and Bedford, MA. For more information, please visit www.obsidiantx.com.

About Amsokigene Autoleucel (amsoki-cel, formerly OBX-115)

Obsidian leverages its cytoDRiVE^® platform to develop engineered TIL cell therapies. Obsidian’s lead investigational TIL program, amsoki-cel, is a novel engineered tumor-derived autologous T cell immunotherapy (tumor-infiltrating lymphocyte [TIL] cell therapy) armored with pharmacologically regulatable membrane-bound IL15 (mbIL15). Amsoki-cel has the potential, if approved, to become a meaningful therapeutic option for patients with advanced (unresectable or metastatic) melanoma and other solid tumors by leveraging the expected benefits of mbIL15 and Obsidian’s proprietary, differentiated manufacturing process designed to enhance persistence, antitumor activity, and clinical safety of TIL cell therapy. Obsidian is investigating amsoki-cel in the phase 1/2 Agni-01 multicenter trial in patients with advanced solid tumors (NCT06060613).

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. In some cases, you can identify forward-looking statements by the following words: “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “aim,” “may,” “ongoing,” “plan,” “potential,” “predict,” “project,” “should,” “will,” “would” or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. Such statements include, but are not limited to, implied and express statements concerning beliefs and expectations regarding: future clinical development activities, therapeutic potential, clinical benefits and safety of Obsidian’s product candidates; potential indications and patient populations for amsoki-cel, if approved, and expectations regarding timing, progress, objectives or plans for Obsidian’s development of its clinical pipeline and interactions with regulatory agencies.

These forward-looking statements relate to Obsidian, its business, prospects and results of operations, and are subject to certain risks and uncertainties posed by many factors and events that could cause Obsidian’s actual business, prospects and results of operations to differ materially from those anticipated by such forward-looking statements. Actual results and the timing of events could differ materially from those anticipated in such forward-looking statements as a result of various risks and uncertainties, including, without limitation: Obsidian’s ability to advance amsoki-cel through clinical development, and to obtain regulatory approval of amsoki-cel; the results of preclinical studies, or clinical studies not being predictive of future results in connection with future studies; the initiation, timing, progress and results of clinical trials; Obsidian’s ability to fund its development activities and achieve development goals; Obsidian’s dependence on third parties to conduct clinical trials and manufacture amsoki-cel; Obsidian’s ability to attract, hire and retain key personnel, and protect its intellectual property; Obsidian’s financial condition and need for substantial additional funds in order to complete development activities and commercialize amsoki-cel, if approved; regulatory developments and approval processes of the U.S. Food and Drug Administration and comparable foreign regulatory authorities; Obsidian’s competitors and industry; and other risks and uncertainties described under the heading “Risk Factors” included in the Quarterly Report on Form 10-Q for the quarter ended June 30, 2026. Readers are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this release. These forward-looking statements are based upon Obsidian’s current expectations and involve assumptions that may never materialize or may prove to be incorrect. We undertake no obligation to revise any forward-looking statements in order to reflect events or circumstances that might subsequently arise, except as required by applicable law.

View source version on businesswire.com: https://www.businesswire.com/news/home/20261002432178/en/

Inquiries:
Caroline Code
VP Corporate Development and Investor Relations
ir@obsidiantx.com

Source: Obsidian Therapeutics, Inc.

Key Terms

immune-checkpoint inhibitor medical

An immune-checkpoint inhibitor is a type of drug that removes the “brakes” on the body’s immune system so white blood cells can better find and destroy cancer cells, like taking down a security gate to let guards access an intruder. Investors care because these drugs can become high-value therapies with large market demand, but they also involve long, costly development, regulatory risk, and variable patient responses that affect commercial and clinical outcomes.

tumor-infiltrating lymphocyte medical

Immune cells, mainly T cells, that have moved from the bloodstream into a tumor and are present among the cancer cells and supporting tissue; they are identified by examining tumor tissue with microscopy or molecular tests. Tumor-infiltrating lymphocytes (TILs) can include different types of lymphocytes (for example, CD8+ cytotoxic T cells and CD4+ helper T cells) and indicate an immune system interaction with the tumor, but their presence or number does not by itself prove those cells are effectively killing cancer cells. TILs are also the source material for certain cancer immunotherapies, where these cells are isolated, sometimes expanded outside the body, and returned to the patient.

first-in-human medical

A first-in-human study is the initial test of a new drug, medical device, or therapy in people to check safety, side effects and appropriate dosing. It matters to investors because it marks a major development milestone: successful early human testing can reduce scientific and regulatory uncertainty, much like moving a prototype from the workshop to a real-world test drive, and often affects a company’s valuation and funding prospects.

lymphodepletion medical

Lymphodepletion is a short medical treatment that lowers a patient’s lymphocytes, the immune cells that can interfere with certain cell-based therapies, to create a more supportive environment for the new therapy to work. Think of it like clearing a crowded garden bed before planting seeds: by temporarily reducing competing cells, the engineered therapy can take hold more effectively. Investors watch lymphodepletion because it affects clinical trial results, safety profiles, treatment adoption, and overall commercial potential.