Novartis to Start Final-Stage Test of Blood Thinner

Portola Pharmaceuticals Inc. said its partner Novartis AG will begin final-stage testing of the experimental blood thinner elinogrel after researchers found it worked quickly in patients who had surgery to unblock an artery.

Elinogrel took effect within a half hour to keep the blood’s platelets from sticking together and forming a clot, researchers who conducted an earlier study said at the European Society of Cardiology conference in Stockholm. The drug left patients at a higher risk of bleeding requiring medical attention and liver complications than the standard therapy of Sanofi-Aventis SA and Bristol-Myers Squibb Co.’s Plavix.

The 29-month final trial will start next year and differ from the previous study by testing only oral use in stable heart disease patients, said William Lis, chief executive officer of South San Francisco, California-based Portola, in an interview in Stockholm. Researchers won’t know how elinogrel compares to other blood thinners until that trial is finished, said Robert Harrington, a professor of medicine at Duke University and the chairman of the earlier trial’s steering committee.