Astria Therapeutics Announces Closing of Underwritten Offering and Full Exercise of Underwriters' Option to Purchase Additional Shares

Astria Therapeutics, Inc. ("Astria Therapeutics," "Astria," the "Company," "our," or "us") (Nasdaq: ATXS), a biopharmaceutical company developing STAR-0215 for the treatment of hereditary angioedema and focused on life-changing therapies for rare and niche allergic and immunological diseases, today announced the closing of its previously announced underwritten offering of 10,445,050 shares of its common stock, including the full exercise of the underwriters' option to purchase 1,362,397 shares of common stock, at a price of $11.01 per share. The gross proceeds of the offering were approximately $115 million, before deducting underwriting discounts and commissions and other offering expenses. All shares in the offering were offered by the Company.

Jefferies and Evercore ISI acted as joint book-running managers for the offering. LifeSci Capital and Oppenheimer & Co. acted as co-lead managers and H.C. Wainwright & Co. acted as co-manager for the offering.

The shares described above were offered pursuant to a shelf registration statement on Form S-3 (File No. 333-264911), which was declared effective by the Securities and Exchange Commission (the "SEC") on May 23, 2022. The offering was made only by means of a prospectus supplement and the accompanying prospectus. A prospectus supplement relating to the offering has been filed with the SEC and is available at www.sec.gov. Copies of the prospectus supplement and the accompanying prospectus may be obtained for free by contacting Jefferies LLC, Attention: Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, NY 10022, by telephone at (877) 821-7388, or by email at [email protected]; or Evercore Group L.L.C., Attention: Equity Capital Markets, 55 East 52^nd Street, 35^th Floor, New York, NY 10055, or by telephone at (888) 474-0200, or by email at [email protected].

This press release does not constitute an offer to sell or the solicitation of an offer to buy any of the shares described herein, nor shall there be any sale of these shares in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to the registration or qualification under the securities laws of any such jurisdiction.

About Astria Therapeutics

Astria Therapeutics is a biopharmaceutical company, and our mission is to bring life-changing therapies to patients and families affected by rare and niche allergic and immunological diseases. Our lead program, STAR-0215, is a monoclonal antibody inhibitor of plasma kallikrein in clinical development for the treatment of hereditary angioedema.