Competition looming for Amgen, Glaxo with blood clot drugs

NEW YORK (CNNMoney.com) -- The biotech Amgen and the drugmaker GlaxoSmithKline announced similar results for experimental blood-clotting drugs and could find themselves locking horns in the near future.

Amgen's (up $0.18 to $70.06, Charts) experimental drug, AMG 531, caused 86 percent of patients to improve their platelet count. Platelets help the body form blood clots to stop bleeding. The biotech announced the findings at the annual conference of the American Society of Hematology in Orlando, Fla.

GlaxoSmithKline (down $0.13 to $52.39, Charts), at the same conference, announced that its experimental drug, Promacta, caused 84 percent of patients to increase their platelet counts when taking the highest dose.

These drugs, if they're successful in further testing and win approval from the Food and Drug Administration, would be used to treat patients with a blood-clotting disorder called ITP. About 200,000 Americans suffer from ITP, an immune system malfunction causing the body to attack its own platelets and destroy its ability to form blood clots. AMG 531 and Promacta ramp up the body's production of platelets to outpace the destruction.

AMG 531 is currently in phase 3 testing, which is the most advanced stage of testing before an experimental drug is submitted to the FDA for review. But the test results that Amgen announced today are the extension of a phase 2 study, which is less advanced. The phase 2 study includes 104 patients, and the interim analysis at 48 weeks focused on 36 of those patients. Amgen expects to complete phase 3 testing this year, and plans to announce its decision on FDA filing early in 2007.

GlaxoSmithKline's test was also based on a phase 2 study, involving 117 patients in a six-week study.

Amgen, based in Thousand Oaks, Calif., is the largest biotech in the world in terms of sales. Genentech (up $0.12 to $83.51, Charts), based in South San Francisco, is the oldest biotech in the world, and the second-largest.

GlaxoSmithKline is one of the largest drugmakers in Europe.

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