PHILADELPHIA, Aug. 15, 2025 /PRNewswire/ -- Berger Montague PC is investigating potential securities fraud claims on behalf of investors of Altimmune, Inc. (NASDAQ: ALT) ("Altimmune" or the "Company") following the filing of a securities class action lawsuit filed on behalf of investors who purchased or otherwise acquired Altimmune securities between August 10, 2023 through June 25, 2025 (the "Class Period").

Investor Deadline: Investors who purchased or acquired Altimmune securities during the Class Period may, no later than October 6, 2025, seek to be appointed as a lead plaintiff representative of the class. To learn your rights, CLICK HERE.

Altimmune, headquartered in Gaithersburg, Maryland, is a clinical-stage biopharmaceutical company.

The lawsuit alleges that on June 26, 2025, Altimmune announced that its IMPACT study had failed to achieve statistical significance in the trial's primary endpoint of fibrosis reduction, citing a higher-than-expected placebo response. Despite management's prior optimistic statements, the Company downplayed the poor results, attributing the outcome to the Phase 2 nature of the trial and suggesting improvements in a future Phase 3 study.

Following this disclosure, Altimmune's stock plunged 53%, from a close of $7.71 per share on June 25, 2025, to a close of $3.61 on June 26, 2025, causing heavy losses for investors.

If you are an Altimmune investor and would like to learn more about this action, CLICK HERE or please contact Berger Montague: Andrew Abramowitz at aabramowitz@bergermontague.com or (215) 875-3015, or Caitlin Adorni at cadorni@bergermontague.com or (267)764-4865.

About Berger Montague

Berger Montague, with offices in Philadelphia, Minneapolis, Delaware, Washington, D.C., San Diego, San Francisco, Chicago, Malvern, PA, and Toronto has been a pioneer in securities class action litigation since its founding in 1970. Berger Montague has represented individual and institutional investors for over five decades and serves as lead counsel in courts throughout the United States.

For more information or to discuss your rights, please contact:

Andrew Abramowitz, Senior Counsel

Berger Montague

(215) 875-3015

aabramowitz@bergermontague.com

Caitlin Adorni

Berger Montague

(267) 764-4865

cadorni@bergermontague.com

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SOURCE Berger Montague