NEW YORK, Aug. 8, 2025 /PRNewswire/ -- 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 (the "Class Period"). If you wish to serve as lead plaintiff, you must move the Court no later than October 6, 2025.

So What: If you purchased Altimmune securities you may be entitled to compensation without payment of any out of pocket fees or costs through a contingency fee arrangement.

What to do next: To join the Altimmune class action, go to https://rosenlegal.com/submit-form/?case_id=22535 or call Phillip Kim, Esq. at 866-767-3653 or email case@rosenlegal.com for more information. A class action lawsuit has already been filed. If you wish to serve as lead plaintiff, you must move the Court no later than October 6, 2025. A lead plaintiff is a representative party acting on behalf of other class members in directing the litigation.

Details of the case: 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.

To join the Altimmune class action, go to https://rosenlegal.com/submit-form/?case_id=22535 or call Phillip Kim, Esq. at 866-767-3653 or email case@rosenlegal.com for more information.

No Class Has Been Certified. Until a class is certified, you are not represented by counsel unless you retain one. You may select counsel of your choice. You may also remain an absent class member and do nothing at this point. An investor's ability to share in any potential future recovery is not dependent upon serving as lead plaintiff.

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Contact Information:

Laurence Rosen, Esq.

Phillip Kim, Esq.

The Rosen Law Firm, P.A.

275 Madison Avenue, 40th Floor

New York, NY 10016

Tel: (212) 686-1060

Toll Free: (866) 767-3653

Fax: (212) 202-3827

case@rosenlegal.com

www.rosenlegal.com

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