Portola reports Phase III antidote data

Portola Pharmaceuticals Inc. (NASDAQ:PTLA) rose $2.68 to $40.76 on Monday after reporting full data from the first part of the Phase III ANNEXA-R study, in which anticoagulant antidote andexanet alfa met all primary and secondary endpoints.

Portola said an IV bolus of andexanet alfa rapidly and significantly reversed the anticoagulant activity of Xarelto rivaroxaban from Bayer AG (Xetra:BAYN) and partner Johnson & Johnson (NYSE:JNJ) compared to placebo (p<0.0001), the trial's primary endpoint. The candidate also reduced the concentration of unbound Xarelto in the plasma (p<0.0001) and restored thrombin levels to the normal range in 26 out of 27 patients. The company reported top-line results in January (see BioCentury Extra, Jan 9). ...