Portola Pharmaceuticals, a South San Francisco-based biopharmaceutical company focused on thrombosis and other hematologic diseases, has received a Complete Response Letter from the US Food and Drug Administration (FDA) requesting additional information primarily related to manufacturing in the company's biologics license application (BLA) for AndexXa (andexanet alfa). AndexXa is an FDA-designated breakthrough therapy that is in development for patients treated with a direct (apixaban, rivaroxaban, or edoxaban) or indirect (enoxaparin) Factor Xa inhibitor when reversal of anticoagulation is needed due to life-threatening or uncontrolled bleeding.

The FDA has also asked for additional data to support inclusion of edoxaban and enoxaparin in the label, and indicated it needs to finalize its review of the clinical amendments to Portola's post-marketing commitments that were recently submitted. AndexXa, an investigational drug, is a modified human Factor Xa molecule that acts as a decoy to target and sequester both oral and injectable Factor Xa inhibitors in the blood.

Earlier this year, Pfizer and Bristol-Myers Squibb formed a collaboration agreement with Portola Pharmaceuticals to develop and commercialize andexanet alfa in Japan. Under the agreement, Portola was to receive an upfront payment of $15 million, potential regulatory milestones of $20 million, and sales-based milestones of $70 million as well as compensation based on andexanet alfa net sales. Bristol-Myers Squibb and Pfizer are to co-fund with Portola the development and commercialization of andexanet alfa in Japan. Portola retain rights to andexanet alfa outside of Japan and remains responsible for the manufacturing supply. Portola had previously entered into two separate non-exclusive clinical collaboration agreements with Bristol-Myers Squibb and Pfizer to support Phase II and Phase III development of andexanet alfa and apixaban in the US and the European Union.

Source: Portola Pharmaceuticals