Promising New Developments for Vivus’ Weight-Loss Drug Qnexa

As we have previously written, Vivus’ weight loss drug Qnexa is up for approval in the US in April of this year. Encouragingly, Vivus announced recently that, if approved, Qnexa could be available for use by a broader population than previously anticipated. In October 2010, the FDA chose not to approve Qnexa because of concerns over potential long-term safety issues, including a risk for birth defects (teratogenicity) – see the NewNowNext in diaTribe #26 for more details. In response, Vivus started a study dubbed FORTRESS to better understand the risk, and this is the main study the FDA will use to assess benefit-risk related to the birth-defect concerns. In efforts to make Qnexa available sooner, Vivus resubmitted the drug to the FDA in October 2011 for use by men and women unable to get pregnant who are either obese or overweight with one or more other medical problems (i.e., diabetes, high cholesterol, high blood pressure) – which would account for an estimated 80 million adults in the US. Earlier this month, shortly after Vivus released preliminary results from FORTRESS (in late December 2011), the FDA asked the company to add women of childbearing potential (except pregnant women) to its proposed population for Qnexa use – an encouraging sign that may indicate the FDA now believes the benefits of the drug outweigh its risks. Even so, these recent developments are by no means a guarantee that Qnexa will gain approval. The FDA will host a meeting to discuss the benefits and risks of Qnexa on February 22 and is expected to make its decision whether or not to approve the drug by April 17. –VW