On April 22, 2026, HHS Secretary Robert F. Kennedy Jr. testified before the Senate Finance Committee and defended the FDA's second rejection of Replimune's RP1, an oncolytic immunotherapy for advanced melanoma patients who have run out of options. In doing so, he made two factual claims that oncologists and the trial investigators say are demonstrably false.
Kennedy told senators: “Every panel within FDA, all the career panels, the career scientists who looked at that drug said it was not effective.” He added: “All the people who were tested also received a chemotherapy drug, so we don't know what the effect was.”
Both statements are wrong. The initial FDA advisory panel approved the drug — that decision was overturned by Dr. Vinay Prasad, then-head of the FDA's Center for Biologics Evaluation and Research and a noted skeptic of accelerated approvals, who was appointed roughly two months before the first July 2025 rejection. And the patients in the RP1 trial did not receive chemotherapy. They received nivolumab, a Bristol Myers Squibb anti-PD-1 immunotherapy.
The FDA issued the second Complete Response Letter on April 10, 2026, citing the absence of a control arm. That decision sent Replimune's stock from roughly $4.76 down to a record low of $1.50 within days — a cumulative drop of roughly 70% — and the company has begun laying off hundreds of employees. CEO Sushil Patel said that without accelerated approval, “the development of RP1 will not be viable.”
Dr. Anna Pavlick, a melanoma researcher with 25 years of experience who worked on the trial, told The Wall Street Journal: “I have patients who have been treated with this drug that are still alive today who would otherwise be dead. Honestly, there was no doubt in our minds whatsoever when we completed this study and we saw the results that this was going to be approved as a wonderful alternative for our patients because they have no options.”
Dr. Eric Whitman of the Atlantic Melanoma Center, who also has patients in remission on RP1, said: “When you talk to the melanoma experts, people who treat lots and lots of melanoma patients like myself, it's obvious that this is beneficial to patients and it's saving lives or it has potential to save lives. The community of patients and doctors don't understand the reasoning.”
Roughly 8,500 Americans die of advanced melanoma each year. The trial showed that one in three patients who had failed standard anti-PD-1 therapy went into remission after adding RP1.
Kennedy used the hearing to defend FDA Commissioner Dr. Marty Makary, blaming the backlash on industry pressure: “The industry is so powerful. They own Congress, they own the media, and they can beat up Marty Makary because he's trying to do change over there.” He did not address the factual errors in his characterization of the trial.