2nd UPDATE: FDA Panel Rejects Vivus Weight-Loss Drug Qnexa

15th Jul 2010 22:29

(Updates with FDA comments and other details) By Jennifer Corbett Dooren Of DOW JONES NEWSWIRES WASHINGTON (Dow Jones)--A federal advisory panel Thursday rejected Vivus Inc.'s (VVUS) experimental weight-loss drug Qnexa on concerns potential safety concerns could be magnified if used by millions of patients. Specifically, the panel of non-FDA medical experts voted 6-to-10 against a question that asked whether the panel believed the "overall risk-benefit assessment of Qnexa is favorable to support approval" in obese and certain overweight patients who also have another health problem such as diabetes or high blood pressure. The vote was initially 7-to-9 but one panel member decided to change his vote as the committee discussed the reasons behind its decision. The FDA usually follows its panel recommendations but isn't required to. However, the FDA often considers close votes a split decision. Indeed, Eric Colman, FDA's deputy director of FDA's metabolic and endocrinology products division, said he thought there was hesitancy among panel members who had voted no. "They weren't strongly against the drug but had lingering concerns," Colman said. "I was a little surprised the vote went as it did," given that both ingredients in Qnexa are already on the market in separate drugs. The review of Qnexa by the FDA's endocrinologic and metabolic drugs advisory committee was being carefully watched by other companies with obesity drugs in development. Arena Pharmaceuticals Inc.'s (ARNA) lorcaserin will face an FDA panel in September, and Orexigen Therapeutics Inc.'s (OREX) Contrave is tentatively scheduled for a December panel review. The three drugs use different methods of damping appetite. Shares of both of those companies traded higher during the meeting Thursday but fell sharply after the vote against the Vivus drug. Vivus shares were halted. The FDA said Qnexa resulted in "significant" weight loss, but the agency raised questions about the drug's long-term side effects, including birth defects, depression and an unknown impact on the heart. Some patients in clinical studies had an increase in heart rate. "The real question is when we look at this drug is how safe it is and for how long because this is likely a lifetime therapy," said Lamont Weide, an endocrinologist at the University of Missouri, Kansas City. "I feel uncomfortable with a year's worth of data." Many panel members said they wanted to see more safety data before voting to approve the drug rather than facing potential questions after the drug is approved. Most panel members were also part of the Avandia panel that met earlier this week to discuss whether to keep that drug on the market amid concerns that the diabetes drug raises the risk of heart attacks. Avandia is marketed by GlaxoSmithKline PL (GSK). Qnexa is a controlled-release formulation that combines low doses of two older drugs: the stimulant phentermine, which cuts appetite, and topiramate, which increases the sense of feeling full. Topiramate is sold under the brand name Topamax by Johnson & Johnson (JNJ) to treat migraines and seizures. The FDA said: "Both drugs have reasonably well-established safety profiles because of their widespread use." The FDA looked at whether heart problems potentially linked to phentermine and whether psychiatric side effects and birth defects linked to topiramate would be seen among patients taken Qnexa. Qnexa contains lower amounts of both ingredients. The agency said it was concerned about a "large potential" for women to become pregnant while taking the drug as 34 pregnancies were seen in clinical trials. Women had been instructed to be on birth control and to obtain a negative pregnancy test. -By Jennifer Corbett Dooren, Dow Jones Newswires; 202-862-9294; [email protected] (END) Dow Jones Newswires July 15, 2010 17:29 ET (21:29 GMT)