Subsequent Events

12 Months Ended

Dec. 31, 2015

Subsequent Events [Abstract]

Subsequent Events

15. Subsequent Events

In January 2016, we entered into an agreement with BMS and Pfizer to out license development and commercial rights to develop Andexanet alfa as an antidote for apixaban and other fXa inhibitors in Japan. Under the terms of the agreement we will receive an upfront payment of $15.0 million and are eligible to receive potential regulatory and sales-based milestone payments totaling up to $90.0 million, as well as double-digit royalties based on Andexanet alfa net sales in Japan. BMS and Pfizer will be responsible for all development and regulatory activities for Andexanet alfa in Japan and for commercializing the drug in Japan. Separately, in January 2016 we also entered into a clinical collaboration agreement with Bayer to include its fXa inhibitor, rivaroxaban, in this clinical development program in Japan. Under the terms of the Bayer agreement, we will receive an upfront payment of $5.0 million and are eligible to receive an additional milestone payment based on Japanese regulatory approval of Andexanet alfa as an antidote for rivaroxaban. Bayer will provide technical support as well as fund clinical studies of Andexanet alfa with rivaroxaban in Japan. Bayer received no commercial rights under this agreement.