FDA Panel Surprisingly Ok’s Vivus Diet Pill
February 27th, 2012 // 1:40 pm @ jmpickett
In a surprise move, an FDA panel this afternoon voted overwhelmingly 20-to-2 in favor of recommending that the Qnexa diet pill developed by Vivus should be approved by the FDA. The endorsement marks the first time that an FDA panel had taken such a step during a two-year period in which a trio of new diet drugs were reviewed – and rejected – amid ongoing safety concerns.
The recommendation, which the FDA must decide to accept by April 17, could set the stage for the first new round of prescription diet drugs since fen-phen craze ended more than a decade ago. At the time, one of the two pills comprising that weight-loss combination, which was wildly popular and spawned a multitude of so-called pill mills, was withdrawn due to heart and lung side effects.
In fact, Qnexa contains phentermine, which is the surviving half of the fen-phen cocktail, and topiramate, the active ingredient in the Topamax seizure med. In briefing documents released prior to the meeting, FDA medical reviewers noted concerns over cardiovascular and teratogenic risks – specifically, cleft palates – which prompted the agency to reject the drug in 2010 (see this).
However, the panel was, ultimately, impressed by the amount of weight that patients shed during clinical trials – typically, around 10 percent. At the same time, however, the panelists noted the importance of a follow-up study to track cardiovascular effects, underscoring ongoing caution about the extent to which the FDA has been concerned that a diet pill will be prescribed and used correctly.
Obesity, however, remains a hot topic because of the growing number of overweight people who are at risk for various health complications. And for this reason the FDA panel vote, at least for now, also bodes well for Arena Pharmaceuticals, which hopes to sell its Lorcess pill, and Orexigen Therapeutics, which is seeking agency approval for Contrave.
A key issue for the FDA will involve tracking patient use. Vivus proposed a REMS, or Risk Evaluation and Mitigation Strategy – program, given that Qnexa may be the first new prescription diet drug to be approved in 13 years. The last one was Xenical, a Roche pill that fared poorly due to unpleasant side effects – these were known in the trade as ‘orange undies.’ (An over-the-counter version was marketed sold by GlaxoSmithKline, although this was recently sold). Abbott Laboratories, you may recall, withdrew Meridia from the US market two years ago over cardiovascular issues (see here).
If the agency choose to approve Qnexa, the drug is likely to become a big seller very quickly. To what extent pricing will be an issue remains unclear. Everyone knows that insurers are not rushing to cover drugs that may be taken by a gazillion people who may be able to lose a few pounds through other means, namely diet and exercise. Just the same, trying to lose weight is an American pastime.
