Replimune Group, Inc. Class Action Lawsuit - REPL

The filed complaint alleges that Replimune Group, Inc made materially false and/or misleading statements and/or failed to disclose that: (1) in connection with the BLA, the study design concerns previously communicated by the FDA were not addressed; (2) 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) 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) 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.

In order to be eligible to join the REPL class action lawsuit, you must have incurred a loss on shares of Replimune Group, Inc. purchased during the class period listed above.

If you suffered a loss in Replimune Group, Inc. during the relevant time frame or pursuant to the relevant offering(s), you have until October 5, 2026 to request that the Court appoint you as lead plaintiff. Your ability to share in any recovery doesn't require that you serve as a lead plaintiff.

Key Facts About Replimune Group, Inc. (NASDAQ: REPL)

●       The Allegation: The complaint alleges Replimune misled investors about the regulatory strength of its RP1 Biologics License Application resubmission for advanced melanoma. Plaintiffs allege the company failed to disclose that FDA study design concerns remained unresolved and that the resubmission relied on early unplanned RP1-104 data from only 40 patients, 10% of planned enrollment.

●       The Stock Drop: REPL fell $3.06, or 64.29%, to close at $1.70 per share on April 13, 2026, after Replimune issued a press release discussing the FDA response letter and conceded that the FDA preferred a randomized controlled trial; REPL also fell $1.15, or 19.46%, to close at $4.76 per share on April 10, 2026, after the FDA published a Complete Response Letter rejecting the RP1 BLA.

●       Class Period & Defendants: The class period runs from October 20, 2025 through April 10, 2026, inclusive. The named defendants are Replimune Group, Inc., Sushil Patel (Chief Executive Officer at all relevant times), and Emily Hill (Chief Financial Officer at all relevant times).

●       Lead Plaintiff Deadline: October 5, 2026. Investors who wish to seek appointment as lead plaintiff must apply by the deadline. 

Replimune Class Action Summary
Company	Replimune Group, Inc. (NASDAQ: REPL)
Lead Plaintiff Deadline	October 5, 2026
Class Period	October 20, 2025 - April 10, 2026
Stock Drop	April 10, 2026 - REPL fell $1.15 (19.46%) to $4.76; April 13, 2026 - REPL fell $3.06 (64.29%) to $1.70

Introduction

A securities class action lawsuit has been filed against Replimune Group, Inc. in the District of Massachusetts. The lawsuit covers investors who purchased Replimune securities from October 20, 2025 through April 10, 2026.

The complaint alleges defendants made materially false and misleading statements about the RP1 BLA resubmission. Replimune said it was addressing FDA feedback, but plaintiffs claim key study design problems remained unresolved.

Investors allegedly suffered losses when the FDA rejected the RP1 BLA on April 10, 2026. REPL fell again after Replimune discussed the FDA response letter after market close.

Company Profile

Replimune Group, Inc. is a biotechnology company focused on novel oncolytic immunotherapies. On August 6, 2026, the FDA granted accelerated approval to TUDRIQEV (formerly RP1) in combination with nivolumab for certain adults with unresectable advanced cutaneous melanoma following progression on anti-PD-1 therapy.

Class Period

October 20, 2025 – April 10, 2026

Investors who purchased or acquired Replimune Group, Inc. (REPL) securities during the Class Period may be eligible to seek recovery under federal securities laws.

Allegations

The Replimune securities lawsuit centers on the company's RP1 Biologics License Application resubmission for RP1 in combination with nivolumab to treat advanced melanoma. According to the complaint, Replimune told investors on October 20, 2025 that the FDA had accepted the BLA resubmission, that the company had been working to address agency feedback, and that additional information, data, and analyses were included in the resubmission.

The complaint alleges that Replimune and Chief Executive Officer Sushil Patel reinforced the same regulatory narrative in later public statements. In a November 6, 2025 press release, the company stated that the FDA indicated the IGNYTE-3 trial could potentially support approval and quoted Patel describing the dialogue with the FDA as collaborative and productive. Replimune's November 6, 2025 Form 10-Q also discussed the BLA resubmission, the April 10, 2026 PDUFA date, and the company's plan to interact with the FDA during review.

Plaintiffs allege the same theme continued on February 3, 2026, when Replimune said commercial readiness activities were underway to support a potential launch if RP1 was approved. Patel stated that the company had been engaged with the FDA in the BLA review and that Replimune was ready to launch RP1 with commercial supply produced and the commercial organization prepared to engage target accounts rapidly, assuming FDA approval.

The complaint alleges these statements were materially false and misleading because defendants failed to disclose material adverse facts about the RP1 BLA. Specifically, plaintiffs allege Replimune did not disclose that previously communicated FDA study design concerns had not been addressed, that the company submitted data from an early unplanned RP1-104 analysis involving only 40 patients, 10% of planned enrollment, and that deficiencies in RPL-001-16 and RP1-104 were likely to cause the FDA to reject the BLA.

The Truth Emerges

The alleged truth emerged on April 10, 2026, during market trading, when the FDA published a Complete Response Letter rejecting Replimune's BLA for RP1 in combination with nivolumab. The FDA stated that the evidence presented did not meet the evidentiary standards required for regulatory approval and that exploratory analyses of RPL-001-16 did not change its conclusion that the trial was not an adequate and well-controlled clinical investigation demonstrating substantial evidence of effectiveness.

According to the complaint, the FDA also revealed that Replimune submitted data from an early unplanned analysis of RP1-104 that included only 40 patients, representing 10% of planned enrollment. The FDA said this data was insufficient to support an efficacy claim and that RPL-001-16 could not isolate the contribution of vusolimogene oderparepvec when administered with nivolumab.

After the market closed on April 10, 2026, Replimune issued a press release discussing the FDA's response letter. The company conceded that a randomized controlled trial was preferred by the FDA, while also stating that the FDA had communicated that a single-arm trial could be acceptable for consideration under accelerated approval if the data were sufficiently compelling.

Market Reaction

Following the FDA's publication of the Complete Response Letter during market trading on April 10, 2026, Replimune's share price fell $1.15, or 19.46%, before trading was halted, to close at $4.76 per share on unusually heavy trading volume. The complaint alleges this decline reflected investors' reaction to the FDA's rejection and the disclosed deficiencies in the RP1 BLA submission.

After Replimune's post-market press release on April 10, 2026, the stock continued to decline. REPL fell $3.06, or 64.29%, to close at $1.70 per share on April 13, 2026, again on unusually heavy trading volume.

Next Steps

●       Lead Plaintiff Deadline: October 5, 2026

●       After the lead plaintiff deadline, the Court will consider any lead plaintiff motions.

●       Defendants may file a motion to dismiss.

●       If the case proceeds, the Court may later consider class certification.

Disclaimer: This shareholder alert is for informational purposes only and does not constitute legal advice. Consult a qualified attorney for personalized guidance. Prior results do not guarantee similar outcomes.