The U.S. Food & Drug Administration (FDA) advisors are backing heart studies for obesity drugs. The potential mandate may make it harder to receive regulatory approval for emerging obesity drugs, said Reuters. The agency is not required to adhere to panel recommendations, but generally does.
Three California firms—Vivius Inc, Orexigen Therapeutics Inc., and Arena Pharmaceuticals Inc.—are currently vying for approval of their new weight-loss pills—the first in over a decade. The FDA is expected to issue a decision on Vivus’ drug Qnexa by April 17; Arena’s drug, lorcaserin, goes before an advisory panel May 10. The advisory panel began its hearing on the drugs in Silver Spring, Maryland, on March 28.
Contrave by Orexigen Therapeutics Inc. is facing several years of clinical trials. The FDA ordered Orexigen to conduct a heart safety study before it would consider approving Contrave, said Reuters.
According to Reuters, the U.S. drug advisers say that heart safety studies should be required for new obesity drugs sold in the U.S. in a 17-6 vote in favor of heart impact studies, even if clinical trials do not initially show evidence of increased heart risk. “Anti-obesity drugs have a bad track record of cardiovascular risk,” said Dr. Marvin Konstam, a professor at Tufts University School of Medicine and panel member, wrote Reuters.
Panelists did not reach consensus on whether or not firms should conduct a meta-analysis of existing data before approval, or if they must conduct a full clinical trial that focuses on cardiac safety before new obesity drugs make it to market, said Reuters. A new trial would be very time-consuming and costly, noted some of the advisors.
Most of the panelists did agree that a mandate for a pre-approval trial would be dependent on the drug’s risks and the amount of weight loss a new drug could achieve, said Reuters. The panelists also suggested that patients at increased risk for cardiac disease, such as the elderly, be enrolled heart disease in trials. According to Reuters, the advice is very similar to FDA guidance issued to Type 2 diabetes drug makers. That guidance mandates companies to prove the medications do not increase risks for heart attacks and heart problems, said Reuters.
The panel was convened 15 years after the appetite suppressant, fen-phen, was pulled from the market in 1997 after the combination drug was linked to heart-valve abnormalities. The last obesity drug to be approved by the FDA was Xenical, made by Roche Holding AG, and approved in 1999. In 2010, Abbott Laboratories pulled its weight-loss drug Meridia from the U.S. after a study revealed it increased heart attack and stroke risks in some patients, said Fox News.
Arena’s new diet drug application was just accepted by European regulators, it said. And, an analysis conducted by Vivus on Qnexa’s risks was “somewhat reassuring”; however, the significance of a heart rate increase was “uncertain,” said FDA staff in a February 17 report, according to Bloomberg.com.
Vivus has proposed a post-approval trial to review Qnexa in reducing major heart complications in obese, at-risk patients and would involve 11,300 patients over four and a-half years, said Bloomberg.com. Orexigen agreed with the FDA in September to conduct a two-year study of heart risks for Contrave and will utilize less than 10,000 patients. Orexigen is partnered with Takeda Pharmaceutical Co. Arena is studying lorcaserin for cancer risks and has partnered with Eisai Co.
The FDA previously rejected the three weight loss drugs, asking for additional information on safety risks, including the possibility of birth defects linked to Qnexa.