Altimmune Appoints Richard Eisenstadt as Chief Financial Officer GAITHERSBURG, MD

Altimmune Appoints Richard Eisenstadt as Chief

MD, -- December 13, 2021 -- Altimmune, Inc. (Nasdaq: ALT), a clinical-stage biopharmaceutical company focused on developing treatments for obesity and liver diseases, today

announced the appointment of Richard Eisenstadt as Chief Financial Officer, effective December 31, 2021. Mr. Eisenstadt

succeeds Will Brown, who is leaving Altimmune to pursue other opportunities.

"We are excited to welcome Rich to Altimmune and our executive management team. His extensive experience in financing and managing

drug development and commercial operations will help ensure the company's continued success," said Vipin K. Garg Ph.D., President

and Chief Executive Officer. "I've had the pleasure of working with Rich previously and this is an opportune time for him to join

our team as we accelerate the clinical development of pemvidutide, a potential best-in-class treatment for obesity and NASH, and HepTcell,

an exciting immunotherapeutic and a potential functional cure for chronic hepatitis B. I would like to thank Will for his contributions

over the past years and wish him well in his future endeavors."

Mr. Eisenstadt added, "I am delighted

to join Altimmune and look forward to building on the accomplishments of the team. With the upcoming data readouts in 2022, there is substantial

opportunity to grow and advance the company's clinical pipeline and I am excited for the journey ahead."

Mr. Eisenstadt is an accomplished executive

with over 30 years of leadership experience in healthcare, life sciences, and emerging technology industries. He joins Altimmune from

Aytu BioPharma, Inc., where he served as Chief Financial Officer following its merger with Neos Therapeutics, Inc. in March 2021.

While Chief Financial Officer at Neos, he raised over $340 million in private and public equity and debt financings and supported the

transition of the company from clinical stage to commercial operations. Prior to Neos, Mr. Eisenstadt served as Chief Financial Officer

at Arborgen, Inc., and prior to that, Chief Financial Officer at Tranzyme, Inc., where he was instrumental in its initial public

offering, negotiating several licensing agreements, and financing the company through late-stage clinical development. Mr. Eisenstadt

received an M.B.A. from James Madison University and a B.A. in Economics from the University of North Carolina at Chapel Hill.

is a clinical stage biopharmaceutical company focused on developing treatments for obesity and liver diseases. Altimmune's pipeline

includes next generation peptide therapeutics for obesity, NASH (pemvidutide), and chronic hepatitis B (HepTcell ). For more information

on Altimmune, please visit www.altimmune.com.

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Investor & Media Contacts:

Vipin K. Garg, Ph.D.

President and Chief Executive Officer