Rosen Law Firm, a global investor rights law firm, announces that a shareholder filed a class action on behalf of purchasers of securities Altimmune, Inc. (NASDAQ: ALT) between August 10, 2023 and June 25, 2025. Altimmune describes itself as a “clinical stage biopharmaceutical company focused on developing treatments for obesity, metabolic and liver diseases.”

For more information, submit a form, email attorney Phillip Kim, or give us a call at 866-767-3653.

The Allegations: Rosen Law Firm is Investigating the Allegations that Altimmune, Inc. (NASDAQ: ALT) Misled Investors Regarding its Business Operations.

According to the lawsuit, defendants throughout the Class Period created the false impression that they possessed reliable information pertaining to the results of Altimmune’s IMPACT Phase 2b MASH trial. In truth, Altimmune failed to meet an important statistical significance marker relating to the fibrosis reduction primary endpoint. Altimmune had consistently touted its inflated expectations for positive topline results from the IMPACT Phase 2b MASH trial, while concealing higher responses in the placebo group, which they knew or should have known would negatively impact the topline results. Altimmune’s IMPACT Phase 2b MASH trial results fell short of reality, as shown by Altimmune’s topline data, which show that the statistical significance was not achieved for the fibrosis reduction primary endpoint. When the true details entered the market, the lawsuit claims that investors suffered damages.

What Now: You may be eligible to participate in the class action against Altimmune, Inc. Shareholders who want to serve as lead plaintiff for the class must file their motions with the court by October 6, 2025. A lead plaintiff is a representative party who acts on behalf of other class members in directing the litigation. You do not have to participate in the case to be eligible for a recovery. If you choose to take no action, you can remain an absent class member. For more information, click here.

All representation is on a contingency fee basis. Shareholders pay no fees or expenses.

About Rosen Law Firm: Some law firms issuing releases about this matter do not actually litigate securities class actions. Rosen Law Firm does. Rosen Law Firm is a recognized leader in shareholder rights litigation, dedicated to helping shareholders recover losses, improving corporate governance structures, and holding company executives accountable for their wrongdoing. Since its inception, Rosen Law Firm has obtained over $1 billion for shareholders.

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