FDA Advisory Panel Endorses Replimune’s Melanoma Therapy Despite Data Concerns

By the Editorial Team · Friday, July 31, 2026

An FDA advisory panel voted 10-3 to recommend approval of Replimune Group’s experimental melanoma drug RP1 despite concerns about the reliability of its clinical trial data. This endorsement suggests potential regulatory progress for RP1, though the FDA has yet to make a final decision, and panelists stressed the need for further controlled trials to confirm its effectiveness.

A Food and Drug Administration advisory panel voted 10-3 on Thursday to endorse Replimune Group’s experimental melanoma treatment, RP1, despite ongoing concerns about the reliability of the company’s data and trial design. The panel’s recommendation marks the latest episode in a regulatory process that has extended over nearly two years.

Replimune first submitted its application for RP1, a therapy targeting skin cancer, in November 2024. The FDA initially rejected the drug in July 2025, followed by a rejection of a resubmission in April 2026. In June, the agency permitted a third submission, setting a decision deadline of August 2 and arranging a public advisory meeting several days prior.

During Thursday’s meeting, several panel members characterized Replimune’s data as “messy” and difficult to interpret. Nonetheless, many voted in favor of the drug, citing its potential benefits for patients with melanoma that had been resistant to prior treatments. Some panelists noted that their support was partly influenced by anecdotal evidence presented by experts and patients, many of whom spoke in favor of RP1 during a public comment session involving more than 30 participants.

The FDA’s own review, released earlier this week, raised substantial doubts about the trial’s findings. The agency’s scientists indicated that results from Replimune’s single-arm study were “not interpretable,” noting an inability to determine whether observed tumor responses were attributable to RP1 itself or to a Bristol-Myers Squibb drug administered in combination with it. The review concluded that the study did not represent an “adequate and well-controlled investigation” to demonstrate clear evidence of the drug’s effectiveness.

Despite these concerns, the advisory panel’s positive vote may signal a path forward for RP1, although the agency is not obligated to follow the panel’s recommendation. Panelists emphasized the need for a larger, controlled Phase 3 study to provide more definitive data on the drug’s efficacy.

The deliberations come amid reports that the White House encouraged health officials to reconsider the earlier FDA rejections of RP1. Following the release of the FDA’s critical analysis, Replimune’s stock price fell by more than 30 percent this week.

Thursday’s vote reflects a balancing act between the limited but promising clinical benefits observed in patients and the significant questions raised about the robustness of the existing evidence supporting the therapy. Regulators and company officials now await the FDA’s final decision on RP1, expected early next month.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.