FDA Approves Lorcaserin
The Food and Drug Administration has approved Lorcaserin, the first prescription weight loss medication to win its approval since Orlistat in 1999. Lorcaserin, made by San Diego-based Arena Pharmaceuticals, is one of four weight-loss drugs the FDA has anguished over in recent years. Safety concerns have prompted the agency to order the makers of two other candidate drugs to conduct and comb through additional research. A third drug was withdrawn after it was linked to an elevated suicide risk.
In the 28 months since the makers of Lorcaserin submitted the drug for FDA consideration, the agency also demanded the withdrawal of Meridia after studies showed it increased the risk of heart attack and stroke. That left only two FDA-approved weight-loss drugs on the market: orlistat and the diet pill phentermine.
The result has been — to the growing frustration of many obesity experts — almost no pharmaceutical aid for a steadily growing population of Americans desperate for help in shedding pounds.
Lorcaserin offers would-be dieters modest benefits. One clinical trial found that two-thirds of patients on the drug lost 5% of their body weight, while one-third lost at least 10%, after one year of taking the drug as a supplement to diet and exercise. Subjects' average weight loss was 17 to 18 pounds.
As a means of boosting weight loss results without surgery, Lorcaserin “addresses one of the greatest therapeutic gaps we have in medicine,” said Dr. Arya M. Sharma, an obesity expert and professor of medicine at the University of Alberta in Canada.
The FDA's decision came after the makers of Lorcaserin eased fears, raised in clinical trials, that the drug might damage heart valves. Experts were also worried that animals given a higher dose than the amount intended for patients had an increased incidence of brain and breast tumors.
By last May, Arena and its partner, Tokyo-based Eisai Pharmaceuticals, brought the FDA data showing that such worrisome side effects were highly unlikely to emerge at the doses it expected patients would be prescribed.
On Wednesday, Arena said it would conduct further studies to assess the safety and effectiveness of Lorcaserin’s long-term use and its safety for weight management in children. The drug is not FDA-approved for children, but doctors may legally prescribe it to them off-label.
Still to come are FDA decisions on two other weight-loss drug candidates. Qnexa, a combination of the diet drug phentermine and the anticonvulsant topiramate, sponsored byVivus Inc. of Mountain View, is now under review by the FDA.