REPL Stock Clocks Worst Day In Over 3 Months — New FDA Documents Leave Wall Street Awaiting Another Rejection For Cancer Drug

Wall Street now views the path to clearance for RP1 as increasingly uncertain following two prior rejections.

• Replimune is seeking accelerated approval for RP1 in combination with nivolumab for certain advanced melanoma patients who progressed after anti-PD-1 therapy. 
• Wedbush remains guarded on final approval odds given the FDA’s strongly critical stance.
• BMO sees Replimune facing a difficult session at Thursday’s advisory committee meeting.

Shares of Replimune Group Inc (REPL) closed 38% lower on Tuesday, clocking its worst day since early April, after the U.S. Food and Drug Administration released documents that put a possible approval for its experimental cancer drug in question.

Wall Street now views the path to clearance for RP1 as increasingly uncertain following two prior rejections.

Replimune’s Experimental Drug

Replimune is seeking accelerated approval for RP1 in combination with nivolumab for certain advanced melanoma patients who progressed after anti-PD-1 therapy.

This is the company’s third attempt. The FDA issued complete response letters in July 2025 and April 2026. Both letters said the single-arm mid-stage IGNYTE trial was not an adequate and well-controlled study. Regulators flagged two main problems: the trial could not clearly show how much of the benefit came from RP1 versus nivolumab alone, and the mixed patient group made the results hard to interpret.

In June, the agency accepted Replimune’s latest resubmission, set an August 2 decision deadline, and scheduled an advisory committee meeting for July 30.  

The FDA documents released earlier on Tuesday, ahead of the committee meeting, repeated the core objection: the application still lacks an adequate, well-controlled investigation that demonstrates substantial evidence of effectiveness.

Wall Street Weighs In

Wedbush said the FDA is sticking to its guns, noting inadequacies in the IGNYTE study design and unclear contribution of components. The firm nonetheless anticipates a favorable panel vote on whether the efficacy results are evaluable and clinically meaningful, citing a clear response advantage over historical outcomes with immune-checkpoint inhibitor monotherapy alone. Panelists are expected to find the signal persuasive, though Wedbush remains guarded on final approval odds given the agency’s strongly critical stance. Wedbush carries a Neutral rating on REPL and a $9 price target, implying a potential upside of 4% from Tuesday’s close.  

BMO Capital’s Evan Seigerman, meanwhile, described the briefing documents as negative in tone. BMO sees Replimune facing a difficult session at Thursday’s meeting, with the agency appearing consistent with the positions taken in earlier complete response letters. The firm rates the shares Outperform with a $16 target, suggesting 85% upside.  

How Did REPL Retail Traders React?

On Stocktwits, retail sentiment around REPL stock jumped from bullish to extremely bullish territory over the past 24 hours, while message volume jumped from high to extremely high levels. 
According to the platform’s internal data, retail chatter around the stock has jumped about 1,678% over the past seven days alone.

A Stocktwits user said that the FDA’s stance is clear, dismissing chances for approval.

Another user wondered if the FDA would approve the drug while limiting its use.

REPL stock has fallen 45% year-to-date. 

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