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Altimmune, Inc.

Securities Class Action

  • Date:
  • 10/6/2025
  • Company Name:
  • Altimmune, Inc.
  • Stock Symbol:
  • ALT
  • Class Period:
  • FROM 8/10/2023 TO 6/25/2025
  • Status:
  • Filed
  • Filing Date:
  • 8/5/2025
  • Court:
  • U.S. District Court: District of Maryland

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Bragar Eagel & Squire, P.C., a nationally recognized stockholder rights law firm, announces that a class action lawsuit has been filed against Altimmune, Inc. (“Altimmune” or the “Company”) (NASDAQ:ALT) in the United States District Court for the District of Maryland, Southern Division on behalf of all persons and entities who purchased or otherwise acquired Altimmune securities between August 10, 2023 and June 25, 2025, both dates inclusive (the “Class Period”). Investors have until October 6, 2025 to apply to the Court to be appointed as lead plaintiff in the lawsuit.

According to the complaint, on June 26, 2025, Altimmune published a press release announcing topline results from the IMPACT Phase 2b MASH trial of Pemvidutide in the Treatment of MASH. While defendants had continuously provided inflated expectations ahead of these results, the analysis showed a pointed failure by the Company to achieve statistical significance in its analysis of the fibrosis reduction primary endpoint in its IMPACT Phase 2b MASH trial. In particular, while a positive trend in fibrosis improvement was observed, statistical significance was not met due to a higher-than-expected placebo response. When questioned about this concerning miss, defendants answered indifferently, attributing this result to the Phase 2 nature of the trial and stated that Altimmune was hoping for better results following the Phase 3 trial.
 
Following this news, the price of Altimmune’s common stock declined dramatically. From a closing market price of $7.71 per share on June 25, 2025, Altimmune’s stock price fell to $3.61 per share on June 26, 2025, a decline of 53.2% in the span of just a single day.
 
If you purchased or otherwise acquired Altimmune shares and suffered a loss, are a long-term stockholder, have information, would like to learn more about these claims, or have any questions concerning this announcement or your rights or interests with respect to these matters, please contact Brandon Walker or Marion Passmore by email at investigations@bespc.com, telephone at (212) 355-4648, or by filling out the form below.  There is no cost or obligation to you.
Contact Instructions
Please contact Brandon Walker or Marion Passmore by email at investigations@bespc.com with any questions regarding the case. 
The individual or institution below (“Plaintiff”) has reviewed and agrees to the Bragar Eagel & Squire, P.C. (“BESPC”) retainer agreement and authorizes BESPC to prosecute an action on Plaintiff’s behalf under the federal securities laws or applicable state laws to recover damages on behalf of investors in Altimmune. BESPC will prosecute the action on a full contingency basis and will forward all costs and expenses.
 

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