Clinical hold on COVID-19 vaccine candidate sends Altimmune down 10%

• Altimmune fell as much as 10% on Thursday after the FDA issued a clinical hold on the company's new drug application for AdCOVID, an intranasal COVID-19 vaccine candidate.
• Despite the clinical hold, Altimmune said it does not anticipate a significant impact to its clinical development timeline for the vaccine candidate.
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Altimmune, a clinical-stage biopharmaceutical company, fell as much as 10% on Thursday after the FDA issued a clinical hold on the company's COVID-19 vaccine candidate.

AdCOVID is a single-dose intranasal COVID-19 vaccine candidate in early stages of development by Altimmune. The FDA has requested certain protocol modifications and submission of additional chemistry, manufacturing and controls data.

Altimmune has responded to the FDA's clinical hold letter and at this point does not anticipate a significant impact to its overall development timeline for the vaccine candidate.

Altimmune has surged 557% year-to-date as of Wednesday's close as investors bid up potential COVID-19 vaccine developers.

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