For the third time in less than a year, the Food and Drug Administration has rejected a drug promising to melt the fat away. The agency said yesterday it wouldn’t consider approving the diet drug, Contrave, until its manufacturer conducts a clinical trial to further assess its heart risks.
The FDA hasn’t approved a new diet drug in more than a decade, perhaps chastened by the fen-phen fiasco of the late 1990s. That blockbuster antiobesity medication — a combination of fenfluramine and phentermine — caused severe heart valve problems and pulmonary hypertension in some users before it was pulled from the market in 1997.
Fenfluramine was found to be the culprit.
Last year, the FDA declined to approve two other drugs, Qnexa and Lorqess, because of concerns about the drugs’ side effects: Qnexa was linked to suicidal thoughts, heart palpitations, and memory loss; Lorqess posed unknown safety risks for those with heart disease and diabetes, who weren’t included in the manufacturer’s clinical trials.
FDA officials were also instrumental in getting Meridia withdrawn from the market last October by
But Contrave was seen as far more promising after an FDA advisory committee in December voted in favor of approving the drug.
“We are surprised and extremely disappointed with the agency’s requirement in light of the extensive discussion and resulting vote on this topic at the Dec. 7 advisory committee meeting,’’ Michael Narachi, chief executive of the manufacturer, Orexigen, said in a statement.
The company, based in La Jolla, Calif., did not say whether it will continue to pursue approval for Contrave.
Orexigen does not have any products on the market, making Contrave a key to the company’s future. In trading yesterday, Orexigen shares tumbled $6.59, or 73 percent, to $2.50.
Company studies of the drug, a combination of an antidepressant and an antiaddiction drug to curb appetite, showed it had modest weight-loss benefits. But FDA scientists and safety advocates complained that the company enrolled few elderly patients or patients with a history of heart disease in its trials, making it difficult to determine the drug’s safety in patients who are likely to need it most.
Given the drug’s limited benefit, the FDA’s rejection was not surprising, according to drug industry analyst Erik Gordon.
“You have life-threatening possible side effects in return for modest weight loss that might not be produced in the real world — no wonder the FDA wants more data,’’ said Gordon, a professor and analyst at the University of Michigan’s Ross School of Business.