WOBURN, Mass., July 30, 2026
Replimune Group, Inc. announced a favorable outcome from the U.S. Food and Drug Administration’s Cellular, Tissue, and Gene Therapies Advisory Committee (CTGTAC), which voted 10 to 3 that efficacy results from the IGNYTE study of RP1 (vusolimogene oderparepvec) are evaluable and clinically meaningful. The committee reviewed Replimune’s resubmitted Biologics License Application (BLA) for RP1 in combination with nivolumab for the treatment of advanced melanoma in patients whose disease has progressed following prior anti-PD-1 therapy. The positive advisory committee vote represents an important regulatory milestone for Replimune’s lead oncolytic immunotherapy candidate as the FDA continues its review. The agency’s target action date under the Class 1 BLA resubmission is August 2, 2026. While advisory committee recommendations are not binding on the FDA and the vote does not constitute regulatory approval, the outcome provides support for the clinical relevance of the efficacy evidence generated in IGNYTE.
FDA Panel Backs Clinical Meaningfulness of IGNYTE Data
During the meeting, the advisory committee considered whether the single-arm IGNYTE study, based on its design and conduct, could provide a reliable assessment of expected response rate and durability of response in the proposed advanced melanoma population. Members also discussed whether the response rate and duration of response observed in IGNYTE were clinically meaningful and whether the reported responses indicated systemic antitumor activity attributable to RP1. Following the discussion, the committee voted 10 to 3 in favor of the question asking whether the efficacy results from IGNYTE were evaluable and clinically meaningful. The outcome is particularly significant for Replimune because the BLA seeks authorization for a population of advanced melanoma patients who have already experienced disease progression on anti-PD-1 therapy and therefore face a need for additional treatment options. Replimune said it plans to continue working with the FDA as the agency completes its regulatory review ahead of the target action date.
RP1 Designed to Generate Systemic Antitumor Immunity
Osteosarcoma is the most common malignant bone tumor and frequently affects children, adolescents and young adults, with a median age at onset of approximately 20 years. According to Hansoh Pharma, around 20% to 30% of patients with localized osteosarcoma and approximately 80% of patients with metastatic disease eventually progress to advanced recurrent or metastatic disease. The five-year survival rate for advanced osteosarcoma remains approximately 20%, highlighting the substantial need for new treatment strategies. Options are particularly limited after failure of first- and second-line systemic therapies, with no clearly defined global standard of care for recurrent or refractory disease. Ris-Rez is designed to selectively target the B7-H3 antigen expressed on tumor cells and deliver a topoisomerase inhibitor payload directly into those cells. This targeted ADC strategy is intended to generate potent antitumor activity while limiting systemic exposure to its cytotoxic payload.
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FDA Decision Represents Next Key Milestone for RP1
The favorable CTGTAC vote moves attention toward the FDA’s final review of the RP1 BLA resubmission, with the target action date scheduled for August 2, 2026. Replimune described the committee outcome as an important step for patients with advanced melanoma whose disease has progressed despite prior anti-PD-1 treatment. However, RP1 remains investigational for the proposed advanced melanoma indication, and the FDA is not required to follow the advisory committee’s recommendation when reaching its final regulatory decision. The regulatory review therefore remains the critical next milestone for the program. If ultimately authorized, RP1 combined with nivolumab would introduce an oncolytic immunotherapy strategy aimed at generating both direct tumor destruction and systemic immune activity in a difficult-to-treat melanoma population. For Replimune, the 10–3 advisory committee vote supporting the evaluability and clinical meaningfulness of the IGNYTE efficacy results provides an important regulatory validation point as the company awaits the agency’s decision. The outcome also places increased attention on the potential role of engineered oncolytic viruses in combination immunotherapy approaches for advanced solid tumors.
Source: Replimune press release
