Portola Pharmaceuticals has entered into a clinical collaboration with Daiichi Sankyo to develop andexanet alfa as an antidote for edoxaban, Daiichi Sankyo’s Factor Xa inhibitor, in Japan.

Portola is developing andexanet alfa, a U.S. Food and Drug Administration (FDA)-designated breakthrough therapy, for patients treated with a direct or indirect Factor Xa inhibitor when reversal of anticoagulation is needed, such as for life-threatening or uncontrolled bleeding or emergency surgery and urgent procedures.

Portola will receive an upfront payment and is eligible to receive an additional milestone payment based on Japanese Ministry of Health, Labor and Welfare (MHLW) approval of andexanet alfa as an antidote for edoxaban. Daiichi Sankyo will provide technical support and fund all clinical studies of andexanet alfa with edoxaban in Japan. Daiichi Sankyo will receive no commercial or financial rights under this agreement.

This agreement follows recent agreements with Bristol-Myers Squibb (BMS), Pfizer Inc. and Bayer Healthcare to develop and commercialize andexanet alfa in Japan. Under those agreements, BMS and Pfizer will be responsible for development, regulatory and commercial activities for andexanet alfa in Japan. Bayer will fund development of andexanet alfa as an antidote for rivaroxaban in Japan. Under this new agreement with Daiichi Sankyo, edoxaban will also be included in the andexanet alfa clinical development program in Japan.

Portola previously entered into eight separate non-exclusive clinical collaboration agreements with Daiichi Sankyo, BMS, Pfizer, Bayer and Janssen to support Phase 2 and Phase 3 studies of andexanet alfa and edoxaban in the U.S., Europe and Japan. Portola may receive additional payments under these agreements. Portola retains all rights, including full commercial and financial rights, for andexanet alfa outside of Japan.