Portola Pharmaceuticals Announces Proposed Offering of Common Stock

SOUTH SAN FRANCISCO, Calif., March 9, 2015 (GLOBE NEWSWIRE) -- Portola Pharmaceuticals, Inc. (Nasdaq:PTLA) today announced that it has commenced an underwritten public offering of shares of its common stock and expects to raise gross proceeds of approximately $100,000,000. All of the shares of common stock in the offering will be sold by Portola Pharmaceuticals. Subject to market and other conditions, the offering is expected to price before 9:30 a.m., EDT, on March 10, 2015.

Morgan Stanley is acting as the book-running manager for the offering. A registration statement related to the offering has been filed with the Securities and Exchange Commission. A preliminary prospectus supplement and final prospectus supplement, when available, may be obtained from the offices of Morgan Stanley & Co. LLC, Attention: Prospectus Department, 180 Varick Street, 2nd Floor, New York, NY 10014, or by email at prospectus@morganstanley.com.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy, 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. Any offer, if at all, will be made only by means of a prospectus, including a prospectus supplement, forming a part of the effective registration statement.

About Portola Pharmaceuticals, Inc.

Portola Pharmaceuticals is a biopharmaceutical company developing product candidates that could significantly advance the fields of thrombosis and other hematologic diseases. The Company is advancing its three wholly-owned programs using novel biomarker and genetic approaches that may increase the likelihood of clinical, regulatory and commercial success of its potentially life-saving therapies. Portola's partnered program is focused on developing selective Syk inhibitors for inflammatory conditions.

Forward-Looking Statements

This announcement contains forward-looking statements, including statements relating to Portola Pharmaceuticals' expectations regarding the completion, timing and size of the proposed public offering. These statements are subject to significant risks and uncertainties and actual results could differ materially from those projected. Portola Pharmaceuticals cautions investors not to place undue reliance on the forward-looking statements contained in this release. These risks and uncertainties include, without limitation, risks and uncertainties related to market conditions and satisfaction of customary closing conditions related to the public offering. There can be no assurance that Portola Pharmaceuticals will be able to complete the public offering on the anticipated terms, or at all. Risks and uncertainties relating to Portola Pharmaceuticals and its business can be found in the "Risk Factors" section of Portola Pharmaceuticals' Form 10-K for the year ended December 31, 2014 filed with the SEC on March 2, 2015, and in the preliminary prospectus supplement related to the proposed offering filed with the SEC. Portola Pharmaceuticals undertakes no duty or obligation to update any forward-looking statements contained in this release as a result of new information, future events or changes in Portola Pharmaceuticals' expectations.

CONTACT: Media: Joey Fleury, BrewLife, jfleury@brewlife.com, 415.946.1090 Investors: Alexandra Santos, Portola Pharmaceuticals, ir@portola.com, 650.246.7239

Source:Portola Pharmaceuticals