Merck, Portola Pharmaceuticals sign deal worth up to $420 million to develop anticlotting drug

Merck, Portola in $420M deal for anticlotting drug

WHITEHOUSE STATION, N.J. — Merck & Co. and Portola Pharmaceuticals Inc. say they have an exclusive deal to develop and market an experimental drug to prevent strokes in people with a dangerous irregular heart rhythm.

Merck, the world’s eighth-biggest drugmaker, will pay Portola $50 million initially to license the drug, called betrixaban.

The drug prevents blood clots by blocking a clotting substance called Factor Xa. The pill would be taken daily by people with atrial fibrillation, a sometimes deadly abnormal heart rhythm.

Betrixaban is currently in mid-stage testing. Merck would cover costs of future testing. If that goes well and the drug is approved for sale, Portola could earn up to $420 million in payments from Merck, plus sales royalties.