Weight-Loss Drug Passes Clinical Test

The first new weight-loss drug in more than 20 years moved a step closer Thursday to federal approval.

In presentations to a Food and Drug Administration advisory committee, medical specialists said that experimental studies with the drug, known as dexfenfluramine, showed most obese patients who took daily doses for six months registered weight losses of 5% to 10%. The patients were kept on a diet of 900 calories a day.

After discussing results of the drug at a daylong hearing, the panel on endocrinologic and metabolic drugs concluded the drug was effective. But some panel members raised questions about its safety, saying they leaned toward full approval only after safety questions are resolved. The agency almost always follows its committee recommendations.

Dr. Bobby W. Sandage Jr., an obesity specialist, said that 15-milligram daily doses of the drug--which manufacturer Interneuron Pharmaceuticals Inc. calls Redux--”produced a significant beneficial effect” on users in both six-month and 12-month trials.

Redux works by making the brain think a person is full. Studies of more than 4,000 patients showed that Redux, when taken while dieting, helped 40% of them lose up to 10% of their weight--twice as many pounds as patients who took a dummy pill.

However, as the first new obesity drug since 1973, dexfenfluramine has been shown to cause brain damage in animals at very high doses. Panel members said they needed to resolve questions about that, even though the manufacturer claimed that the levels suggested for human weight loss are too low for any concern.

Panel chairman Dr. Henry G. Bone, senior staff physician at Henry Ford Hospital in Detroit, said his committee would postpone a recommendation for the time being in view of safety questions.

To date, the majority of approved obesity drugs are amphetamines, which can be addictive. However, Dr. Theodore J. Cicero said on behalf of the manufacturer that dexfenfluramine “has a remarkably low record of abuse, with no reported cases in the world since 1970.”

Judith Stern, vice president of the American Obesity Assn., told the committee that “we are literally in the midst of an obesity epidemic” with the need for a better drug to treat an estimated 78 million dangerously overweight Americans.