Growing its cardiovascular research portfolio, Portola Pharmaceuticals Inc. in-licensed an antithrombosis program from Millennium Pharmaceuticals Inc., the company from which it was spun.

Specifically, South San Francisco-based Portola gained exclusive access to a Factor Xa inhibitor program that features a clinical-stage product. Given orally once a day, the lead small molecule acts directly on the blood coagulation enzyme, a target involved in the generation of thrombin.

"When we were spun out in November 2003, we took platelet biology programs from Millennium focused on thrombosis," Matt Birrell, Portola's senior manager of business operations, told BioWorld Today. "The lead program is an ADP receptor antagonist focused on preventing arterial thrombosis. This newly licensed program is focused on venous thrombosis. So the programs are complementary and fit into an overarching theme of the platelet in thrombosis."

In exchange for rights to develop, market and commercialize Factor Xa inhibitors worldwide, Portola agreed to make milestone and royalty payments to Cambridge, Mass.-based Millennium upon achievement of certain events. The deal included no up-front considerations.

The lead compound acquired in the transaction has yet to receive a name, but it has been tested in Phase I studies. Birrell said further Phase I trials would get under way as Portola looks to advance the compound on its own.

The product will be developed for venous thrombosis, and Birrell noted that compounds from the same class have been evaluated for their use in preventing deep-vein thrombosis in patients undergoing hip- and knee-replacement surgery. There are 750,000 such procedures in the U.S. every year. The product also could be developed for stroke and myocardial infarction in atrial fibrillation patients.

The in-licensing deal also included the backup chemistry behind the lead compound.

"We haven't identified a second-generation compound," Birrell said, "but we have the ability to do so."

Just as both of privately held Portola's programs have roots at Millennium, so do the members of its executive team who founded Portola. Many of them made up the cardiovascular and drug discovery group at Millennium's South San Francisco location. They previously had been at COR Therapeutics Inc., with which Millennium merged two years earlier in a $2 billion stock transaction. (See BioWorld Today, Dec. 7, 2001.)

Its initial program, the ADP receptor antagonist, remains in preclinical development.

"We plan to be in clinical trials [with that product] by the middle of next year," Birrell said.

Portola raised $21 million in a Series A funding late last year to fund its initial research. Designed to last two years, Birrell said the financing would be sufficient to support both of the company's programs. (See BioWorld Today, Dec. 9, 2003.)