FDA Advisory Committee Votes 10-3 in Favor of Replimune's RP1 Efficacy Data from Ignyte Study

On July 30, 2026, the FDA's Cellular, Tissue, and Gene Therapies Advisory Committee voted 10-3 that efficacy data from Replimune's Ignyte study of RP1 is evaluable and clinically meaningful. The non-binding vote follows two prior FDA rejections of the skin cancer treatment. Following the announcement, Replimune's stock surged over 120%, recovering from a 32% drop earlier in the week. The FDA's target action date for the Biologics License Application is August 2, 2026.

FDA advisory committee vote

• ▪On July 30, 2026, the FDA's Cellular, Tissue, and Gene Therapies Advisory Committee voted 10 to 3 that the efficacy results from Replimune's Ignyte study of RP1 are evaluable and clinically meaningful
• ▪During the July 30, 2026 meeting, the FDA advisory committee considered whether the single-arm Ignyte study allows for a reliable determination of response rate and durability, and whether the reported results are clinically meaningful
• ▪The FDA advisory committee meeting on July 30, 2026, was called to discuss Replimune's Biologics License Application resubmission for RP1 in combination with nivolumab for advanced melanoma
• ▪The FDA's target action date for Replimune's Class 1 Biologics License Application resubmission for RP1 is August 2, 2026

RP1 BLA regulatory history

• ▪The FDA issued its first complete response letter to Replimune on July 22, 2025, stating the single-arm Ignyte trial was not an adequate and well-controlled study
• ▪The FDA issued a second complete response letter to Replimune on April 10, 2026, citing trial design and tumor assessment methodology
• ▪Replimune resubmitted its Biologics License Application for RP1 a third time under a Class 1 review after disagreeing with the FDA's second rejection on April 10, 2026

Stock market reaction

• ▪Replimune's stock surged over 120%, nearly doubling, following the FDA advisory committee's favorable vote on the Ignyte study results on July 30, 2026
• ▪Replimune's shares dropped nearly 32% days prior to the July 30, 2026 vote after FDA reviews stated the company had not provided clear evidence of RP1's efficacy

RP1 mechanism of action

• ▪RP1 is genetically engineered and armed with a fusogenic protein, GALV-GP R-, and GM-CSF to maximize tumor killing potency and activate a systemic anti-tumor immune response
• ▪RP1, or vusolimogene oderparepvec, is Replimune's lead product candidate built on a proprietary strain of herpes simplex virus

Ignyte trial design

• ▪The Ignyte study is sponsored by Replimune with Bristol-Myers Squibb as a collaborator, enrolling 340 participants across the United States, France, Germany, Spain, and the United Kingdom
• ▪The proposed patient population for Replimune's RP1 consists of advanced melanoma patients who have progressed on prior anti-PD-1 therapy