The Law Offices of Frank R. Cruz announces that a class action lawsuit has been filed on behalf of shareholders who purchased or otherwise acquired Replimune Group, Inc. (“Replimune” or the “Company”) (NASDAQ: REPL) securities between October 20, 2025 and April 10, 2026, inclusive (the “Class Period”). Replimune investors have until October 5, 2026 to file a lead plaintiff motion.

What Happened?

On October 20, 2025, Replimune published a press release announcing that the U.S. Food and Drug Administration (“FDA”) had accepted the resubmission of the Biologics License Application (“BLA”) for RP1 in combination with nivolumab for the treatment of advanced melanoma in patients who progress on an anti-PD-1 containing regimen. The Company also claimed that “[d]uring the past few months, Replimune has been working to address agency feedback” and that “[a]dditional information, data and analyses were included in the resubmission which will be part of the BLA review.” The Company also stated that “[t]he FDA indicated this resubmission is considered to be a complete response to the complete response letter received in July 2025.”

However, on April 10, 2026, during market trading, the FDA published a Complete Response Letter (“CRL”) rejecting Replimune’s BLA. The FDA identified several deficiencies for each of the studies—RPL-001-16 (IGNYTE) and RP1-104 (IGNYTE-3)—submitted by Replimune and found that “the evidence as presented does not meet the evidentiary standards required for regulatory approval, and the results of the additional exploratory analyses of the RPL-001-16 data do not alter our initial conclusion that the RPL-001-16 trial is not an adequate and well-controlled clinical investigation that demonstrates substantial evidence of effectiveness.” The FDA further revealed that “[t]o support resubmission of the BLA on October 9, 2025, [Replimune] provided [objective response rate] data from an early unplanned analysis” from RP1-104 which included only 40 patients, 10% of the planned enrollment of 400 patients.

In the CRL the FDA further revealed that it had “clearly communicated” its “concerns with the study design in multiple FDA interactions throughout [Replimune’s] development program,” but that “the study design concerns previously communicated were not addressed, and the contribution of [RP1] to the observed response rate in RPL-001-16 could not be determined.”

On this news, the Company’s share price fell $1.15 or 19.46%, before trading was halted, to close at $4.76 per share on April 10, 2026, on unusually heavy trading volume.

Then, on April 10, 2026, after the market closed, the Company issued a press release discussing the FDA’s response letter for the RP1 BLA. In the press release, Replimune conceded that “a randomized controlled trial was preferred” by the FDA, but also claimed that the FDA communicated that “if the data was sufficiently compelling, a single arm trial could be acceptable for consideration under accelerated approval.”

On this news, the Company’s share price continued to fall $3.06 or 64.29%, to close at $1.70 per share on April 13, 2026, on unusually heavy trading volume.

What Is The Lawsuit About?

The complaint filed in this class action alleges that between October 20, 2025 and April 10, 2026, Defendants made materially false and/or misleading statements, as well as failed to disclose material adverse facts about the Company’s business, operations, and prospects. Specifically, Defendants failed to disclose to investors: (1) that in connection with the BLA, the study design concerns previously communicated by the FDA were not addressed; (2) that the Company had submitted data from an early unplanned analysis from RP1-104, which included only 40 patients (10% of the planned enrollment of 400 patients); (3) that, as a result, RPL-001-16 and RP1-104 both had deficiencies which were likely to cause the FDA to reject the BLA; and (4) that, as a result of the foregoing, Defendants’ positive statements about the Company’s business, operations, and prospects were materially misleading and/or lacked a reasonable basis.