Underwriters exercise overallotment option to purchase additional 480,000 shares in Pharmasset offering

Pharmasset, Inc. (Nasdaq: VRUS) announced today the underwriters of its recent stock offering have exercised their option to purchase an additional 480,000 shares of common stock. The net proceeds to Pharmasset, Inc., after deducting the underwriting discount, from the sale of these additional shares are expected to be approximately $13.2 million. This brings the total expected proceeds of the offering, after deducting the underwriting discount and estimated offering expenses, to $101.1 million. Citi is serving as sole book-running manager for the offering. J.P. Morgan, Baird and Canaccord Genuity are serving as co-managers.

Pharmasset granted the option in connection with its previously announced offering of 3,200,000 shares of common stock at an offering price of $29.00 per share, which is expected to close on May 19, 2010, subject to customary closing conditions.