Optimer Pharmaceuticals and Astellas Announce Collaboration to Commercialize Fidaxomicin

Optimer Pharmaceuticals, Inc.

and Astellas Pharma Europe Ltd. announced today the signing of an exclusive collaboration and license agreement to develop and commercialize fidaxomicin, an investigational antibiotic for CDI, in Europe and certain other countries in the Middle East, Africa and the Commonwealth of Independent States. In return for an exclusive license to fidaxomicin in the territory, Astellas is obligated to pay Optimer an upfront cash payment of approximately $68 million. Optimer is also eligible to receive additional cash payments totaling up to approximately $156 million upon the achievement of certain regulatory and commercial milestones. Furthermore, Astellas is obligated to pay tiered double-digit royalty payments on net sales of fidaxomicin in the Territory. Astellas will be responsible for all future costs associated with the development, manufacturing, and commercialization of fidaxomicin in the territory including the costs of the ongoing Marketing Authorization Application with the European Medicines Agency.