Orexigen, FDA agree on trial design for obesity drug

(Reuters) - Orexigen Therapeutics Inc said it reached an agreement with U.S. health regulators on the design of a heart-safety trial required for the approval of its experimental obesity drug.

The biopharmaceutical company plans to enroll about 10,000 patients in the placebo-controlled trial for demonstrating that the drug Contrave does not unacceptably increase the risk of major adverse cardiovascular events.

Orexigen will conduct the trial under a "special protocol assessment" from the U.S. Food and Drug Administration.

An SPA agreement indicates that the agency is on board with a trial design, making it more likely that the drug would be approved if the trial succeeds.

The FDA declined to approve Orexigen's pill in January 2011, citing Contrave's cardiovascular effects when used long-term in a population of overweight and obese subjects.

Contrave is one of three obesity drugs that the FDA has shot down over safety concerns, along with Arena Pharmaceuticals Inc's lorcaserin and Vivus Inc's Qnexa.