Otsuka Pharma Confirms Purchase of Astex Pharma at $8.50/Share in Cash

Otsuka Pharmaceutical Co., Ltd. ("Otsuka") and Astex Pharmaceuticals, Inc.

("Astex"), announced today that their respective Boards of Directors have unanimously approved a transaction under which Otsuka will acquire all of the outstanding shares of Astex for $8.50 per share in cash representing a 48% premium to the average closing stock price for the prior 30 day period. The purchase price represents a fully diluted equity value of approximately $886 million, calculated using the treasury stock method. Otsuka intends to effect the transaction through a tender offer and expects to close the transaction early in the fourth quarter of 2013, subject to the satisfaction of customary closing conditions.