SANTA CLARA, Calif.--(BUSINESS WIRE)--XenoPort, Inc. (Nasdaq: XNPT) announced today that it is offering to sell, subject to market and other conditions, 4,000,000 shares of its common stock pursuant to an effective shelf registration statement in an underwritten public offering. XenoPort also intends to grant the underwriters a 30-day option to purchase up to an aggregate of 600,000 additional shares of common stock to cover over-allotments, if any. All of the shares in the offering are to be sold by XenoPort. Morgan Stanley & Co. Incorporated is acting as bookrunner for the offering. RBC Capital Markets, LLC and Wedbush PacGrow Life Sciences are acting as co-managers.