Merck drops oral anticoagulant
Merck has given the rights to its oral anticoagulant betrixaban back to Portola Pharmaceuticals after a review of its late stage portfolio.
Betrixaban, an oral Factor Xa inhibitor, is being studied in a phase II trial for the prevention of stroke in patients with atrial fibrillation. The company's decision looks to be based on doubts about the drug's ability to compete in an increasingly competitive therapeutic area.
Data from the phase II EXPLORE-Xa trial showed dose-dependent clinical activity with similar or lower rates of bleeding compared to standard treatment warfarin. But Merck seems to have been unconvinced of the drug's efficacy compared to other new drugs, such as Xarelto and Pradaxa, which are already on the market.
Luciano Rossetti, senior VP at Merck, said the decision was a part of an “ongoing prioritisation” of its late-stage pipeline.
“Merck continues to advance its broad late-stage pipeline and remains committed to delivering medicines for cardiovascular disease,” he added.
Merck had obtained rights to the drug in 2009, paying Portola $50 million up front in a deal that could have been worth up to $420 million if all milestones had been met.
William Lis, chief executive of San Francisco, US-based Portola, said regaining the rights to betrixaban represented a “transformational opportunity” for the company.
The drug is now ready to pass into phase III testing and Lis said Portola would, with its academic partners, look to independently bring betrixaban to the market and will discuss these options with the FDA “in the near future”.
New oral anticoagulants are set to the next big advance in this therapy area with Bayer’s Xarelto and Pfizer’s/BMS’ apixaban all gunning for regulatory approval this year.
Boehringer Ingelheim’s Pradaxa stole a march over its rivals in October when it received approval from the FDA for stroke risk reduction in patients with non-valvular atrial fibrillation.
The drug is the second anticoagulant that Merck has lost from its pipeline in just a matter of months.
In January Vorapaxar showed it caused excess bleeding in patients who had suffered a heart attack or stroke and who were at risk of further cardiovascular problems.