BMS, MEDAREX GLOBAL DEVELOPMENT AND COMMERCIALIZATION COLLABORATION FOR MDX-010 BECOMES EFFECTIVE

Bristol-Myers Squibb (BMS) and Medarex have announced that the global development and commercialization collaboration agreement, previously announced by both companies Nov. 8, 2004, has become effective.

The agreement became effective after all conditions were satisfied, including expiration of the waiting period required under the Hart-Scott-Rodino Antitrust Improvements Act of 1976. Under the collaboration agreement, BMS and Medarex plan to jointly develop MDX-010, a fully human antibody investigational product targeting the CTLA-4 receptor, which is currently in Phase III clinical development for the treatment of metastatic melanoma.

As previously announced, Medarex will receive an initial cash payment of $50 million, of which $25 million will be for a purchase of Medarex's common stock by BMS. In addition, Medarex could receive up to $205 million if all regulatory milestones are met, and up to $275 million in sales-related milestones. Medarex has an option to co-promote and share profits with BMS in the U.S. BMS will receive an exclusive license outside of the U.S. and will pay royalties to Medarex on any commercial sales.