Replimune's shares surged 125.3% in pre-open trading following a decisive advisory committee outcome at the U.S. Food and Drug Administration. The FDA's Cellular, Tissue, and Gene Therapies Advisory Committee voted 10 to 3 on Thursday, July 30, expressing support for the efficacy evidence from Replimune's IGNYTE study of RP1 (vusolimogene oderparepvec) in combination with nivolumab for patients with advanced melanoma who had progressed after prior anti-PD-1 therapy.
The panel's determination that the trial's results were both evaluable and clinically meaningful ran counter to the assessment from FDA staff scientists, who had earlier argued that the single-arm design of the IGNYTE trial left uncertainty about the drug's individual contribution to patient benefit. The advisory committee's vote, while non-binding, shifted market expectations ahead of the company's PDUFA date on or around August 2.
Analysts reacted quickly to the advisory vote. Cantor Fitzgerald raised its rating on Replimune to Overweight from Neutral, citing what it described as a materially higher probability that the agency will reverse its prior Complete Response Letters and grant Accelerated Approval. The firm pointed to the 10-3 vote and compelling testimony from patients and physicians during the committee hearing as central to its more optimistic stance.
Market mechanics amplified the price move. Replimune had plunged roughly 30% on July 28 after FDA pre-meeting briefing documents flagged serious concerns about the IGNYTE trial's design. The strong advisory outcome triggered heavy short-covering, helping the pre-market price climb to about $12.19, nearly erasing the prior selloff.
Broader market conditions also provided a favorable backdrop. The NASDAQ rose 1.09% while the S&P 500 gained 0.50%, reflecting a risk-on tone that supported gains across biotech names in the oncology and gene therapy spaces. Peers in those sectors saw positive movement as investors reacted to the constructive regulatory tone signaled by the advisory committee.
While the FDA is not obliged to follow advisory committees, the agency has often aligned with panel recommendations. As a result, the August 2 decision date now carries meaningfully improved odds in the market's view for Replimune's regulatory path. With that final decision only days away, investors repositioned rapidly to reflect a higher probability of approval for a therapy aimed at a patient population with limited treatment options.
Context and market drivers
- The advisory committee judged the IGNYTE trial results evaluable and clinically meaningful despite prior staff concerns about single-arm design.
- Cantor Fitzgerald upgraded Replimune to Overweight, citing the vote and testimony as reasons for increased approval odds.
- Technical and market factors - including short-covering after a sharp drop on July 28 and a risk-on broader market - contributed to the rapid pre-market recovery to around $12.19.
What remains uncertain
- The advisory committee vote is advisory only; the FDA's final decision on or around August 2 is still pending.
- FDA staff previously raised concerns about the single-arm trial design, and how the agency weighs that issue in the final review remains an open question.