Obsidian Therapeutics (Nasdaq: OBX) reported updated amsoki-cel results in advanced melanoma, with a 67% objective response rate at the recommended phase 2 dose. In the single-arm, open-label Agni-01 study, 15 patients had 2 complete and 8 partial responses. Five responses remained ongoing at median follow-up of 14.3 months; 33% of patients remained in response at 12 months. Median progression-free survival was 8.3 months; median response duration was not reached.
Pooled safety data from 37 patients showed no dose-limiting toxicities, treatment-related deaths, specified immune-cell neurotoxicity or intensive-care transfers; one Grade 3 cytokine release syndrome event occurred. Results will be presented at SITC on November 7, 2026. Obsidian expects registration-enabling cohort enrollment to finish by the end of the first quarter of 2027 and topline data by year-end 2027.
Obsidian Therapeutics (OBX) will present updated amsoki-cel clinical trial data at the SITC annual meeting on November 7, 2026. The meeting runs November 4–8 in Phoenix, Arizona. Amsoki-cel, formerly OBX-115, is an investigational tumor-infiltrating lymphocyte (TIL) cell therapy being studied in advanced melanoma resistant to immune-checkpoint inhibitors.
The data poster will cover pooled safety findings from the Phase 1 single-center first-in-human study and the Phase 1/2 Agni-01 multicenter study. It will also provide an efficacy update for 15 Agni-01 patients treated at the recommended phase 2 dose. A separate trial-in-progress poster, also scheduled for November 7, will describe Agni-01's phase 2 registration-enabling cohort evaluating amsoki-cel in patients with immune-checkpoint inhibitor-resistant advanced melanoma.
Obsidian Therapeutics (Nasdaq: OBX) has enrolled the first patient in the registration-enabling cohort of its Phase 1/2 Agni-01 study evaluating amsokigene autoleucel (amsoki-cel, OBX-115), an engineered TIL cell therapy with membrane-bound IL15, in immune checkpoint inhibitor–resistant advanced or metastatic melanoma. Following discussions with the FDA, the company is pursuing a single-arm design intended to support a future BLA via an accelerated approval pathway, with ORR by blinded central review as the primary endpoint.
The new cohort builds on prior Agni-01 melanoma data showing a 67% objective response rate at the RP2D (10/15 patients), including two complete responses, and a favorable safety profile with low-dose lymphodepletion, no IL2, and no reported dose-limiting toxicities, treatment-related mortality, ICANS, or ICU transfers. Enrollment is anticipated to complete by end of Q1 2027, with topline melanoma data expected by year-end 2027. Amsoki-cel is also being studied in NSCLC, with Phase 1 data expected in the first half of 2027.
Obsidian Therapeutics (Nasdaq: OBX) completed its previously announced merger with Galera Therapeutics and closed an oversubscribed $350 million private placement from a syndicate of new and existing biotechnology-focused investors. The combined company will operate as Obsidian Therapeutics, and its shares are expected to begin trading on Nasdaq under the ticker “OBX” on August 4, 2026.
According to Obsidian, post-transaction cash and cash equivalents of approximately $350 million are anticipated to fund operations into the second half of 2028, including key milestones for lead TIL cell therapy candidate OBX-115: Phase 1 NSCLC data expected in the first half of 2027 and topline melanoma registration-enabling data expected by year-end 2027. Former Galera stockholders own about 1.2%, former Obsidian stockholders about 51.6%, and private placement investors about 47.2% of the combined company’s outstanding common stock. Galera stockholders of record as of July 31, 2026 received a non-transferable contingent value right tied to certain future events.