The Food and Drug Administration approved the first new anti-obesity drug in 22 years Monday, a controversial medicine that essentially fools patients into feeling full so they lose weight.
Dexfenfluramine won FDA approval over the objections of consumer advocates and some doctors, who fear it could cause brain damage or a rare but dangerous lung disorder.
But the FDA said the brain damage so far has been found only in animals, and the lung ailment is rare. Consequently, obese Americans can use dexfenfluramine longer than is allowed for any other appetite suppressant, the agency ruled.
“We believe the benefits outweigh the risks,” said Dr. James Bilstad, FDA’s chief of metabolic drugs.
Dexfenfluramine, created by Interneuron Pharmaceuticals, will be sold by Wyeth-Ayerst Laboratories under the name Redux. It will hit pharmacy shelves this summer and cost consumers approximately $2 per day, the company said.
Obesity, defined as more than 20 percent over ideal weight, causes such ailments as high blood pressure, heart disease and diabetes. Obesity-related diseases kill 300,000 Americans a year.
Doctors typically urge patients to diet and exercise to drop the pounds, but almost all who succeed regain the weight within five years. Until now, patients could take amphetamines, which can be addictive, or the drug fenfluramine to help them lose weight - but none should be used for more than several months because of potential side effects.
Dexfenfluramine is a chemical relative of fenfluramine. The FDA is not restricting how long patients can use it, although its label will warn that dexfenfluramine has not been studied in patients for more than one year.
It won’t work for everybody, the FDA warned Monday. In one study, six out of 10 patients who lost at least 4 pounds during the first month of dexfenfluramine treatment went on to lose up to 10 percent of their body weight by year’s end. Those who hadn’t responded within a month weren’t helped.
Diet and exercise alone helped three out of 10 patients lose as much weight.
But dexfenfluramine patients lost an average total of just 7.5 pounds more than dieters who didn’t take the drug, said Dr. Sidney Wolfe of the patient advocacy group Public Citizen.