Portola Pharmaceuticals, Inc. (PTLA) announced new interim data from a phase II proof-of-concept study evaluating its Factor Xa inhibitor antidote, Andexanet Alfa (PRT4445). The candidate aims to reverse the Factor Xa inhibitor’s anticoagulant activity in patients suffering from uncontrolled bleeding or undergoing emergency surgery.
The study involved healthy volunteers who received Bristol-Myers Squibb Company/Pfizer Inc.’s (BMY)/(PFE) Eliquis, another Factor Xa inhibitor. Eliquis is currently used for reducing the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. In the study PRT4445 was infused for up to two hours after an intravenous bolus dose.
Results from the study showed that the use of intravenous PRT4445 420 mg bolus dose resulted in around 92% reversal of the anticoagulant activity of Eliquis in two minutes. At the conclusion of a two-hour infusion, PRT4445 resulted in around 91% reversal of the anticoagulant activity of Eliquis.
No serious side effects or premature termination of the treatment with PRT4445 has been observed so far in the ongoing safety follow-up of this study.
We remind investors that in Nov 2012, Portola entered into an agreement with Bristol-Myers Squibb and Pfizer to evaluate PRT4445 in combination with Eliquis.
Portola is conducting a phase II study evaluating PRT4445 with another Factor Xa inhibitor, Xarelto. The study intends to evaluate the efficacy and safety of PRT4445 in combination with Xarelto across multiple dosages. The study aims to determine the right dose of PRT4445 that will be able to reverse the anticoagulant activity of Xarelto in case of an uncontrolled bleeding or other emergency situations. The study is expected to be completed by year end.
We note that Portola has been putting in substantial efforts to develop its pipeline. In Oct 2013, the company announced that it has started a phase I/II proof-of-concept study on its oral dual spleen tyrosine kinase (Syk) and janus kinase (:JAK) inhibitor candidate, PRT2070.
PRT2070 is being evaluated for patients suffering from genetically-defined hematologic cancers and patients who have not responded to prior therapy due to relapse or acquired mutations.
Portola carries a Zacks Rank #4 (Sell). Companies that currently look well positioned include Actelion Ltd. (ALIOF) with a Zacks Rank #1 (Strong Buy).