Atara Biotherapeutics Announces Closing of Underwritten Offering of Common Stock and Exercise of Underwriters' Option to Purchase Additional Shares

SOUTH SAN FRANCISCO, Calif., Feb. 18, 2015 (GLOBE NEWSWIRE) -- Atara Biotherapeutics, Inc. (Nasdaq:ATRA), a biopharmaceutical development company with a focus on innovative therapies for patients with debilitating diseases, today announced the closing of its public offering of 4,147,358 shares of its common stock at a public offering price of $18.00 per share, which included 509,025 shares sold pursuant to the partial exercise by the underwriters of their option to purchase additional shares.

Goldman, Sachs & Co. and Citigroup Global Markets Inc. acted as joint book-running managers for the proposed offering. Jefferies LLC acted as co-manager.

A registration statement relating to these securities was declared effective by the U.S. Securities and Exchange Commission on February 11, 2015.

The offering was made only by means of a written prospectus forming part of the effective registration statement. Copies of the final prospectus relating to the offering was filed with the Securities and Exchange Commission and may be obtained from Goldman, Sachs & Co., Attention: Prospectus Department, 200 West Street, New York, New York 10282, by telephone at (866) 471-2526, by facsimile at (212) 902-9316, or by email at prospectus-ny@ny.email.gs.com, or from Citigroup Global Markets Inc., c/o Broadridge Financial Solutions, 1155 Long Island Avenue, Edgewood, NY 11717, by email at prospectus@citi.com or by phone at (800) 831-9146.

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

About Atara Biotherapeutics, Inc.

Atara Biotherapeutics, Inc. is a biopharmaceutical development company focusing on innovative therapies for patients with debilitating diseases. Atara Biotherapeutics' lead programs are focused on myostatin and activin, members of the TGF-beta family of proteins that have demonstrated the potential to have therapeutic benefit in a number of clinical indications. In September 2014, Atara Biotherapeutics entered into an exclusive option agreement with Memorial Sloan Kettering Cancer Center (MSK) under which it has the right to license (pursuant to a negotiated form of license agreement) the exclusive, worldwide rights to three clinical stage T-cell programs, as well as other T-cell programs that are discovered or developed by MSK pursuant to sponsored research funded by Atara Biotherapeutics. 

CONTACT: MEDIA CONTACT:
         Tina Gullotta,
         tgullotta@atarabio.com.
         650-741-1613

         INVESTOR CONTACT:
         Tina Gullotta,
         tgullotta@atarabio.com.
         650-741-1613

Released February 18, 2015