Arena Obesity Drug Shows Early Promise

Arena Pharmaceuticals Inc. said its experimental obesity drug was effective at all three doses in promoting weight loss after three months in a mid-stage clinical trial.

Patients taking the highest dose of 20 milligrams a day lost almost 8 pounds, or about 3.6% of total body weight.

It is expected that U.S. regulators will require a 12-month efficacy study with a goal of 5% weight loss and two years’ worth of safety data before considering approval of the drug, known as APD356, Arena Chief Executive Jack Lief said.