By: Eric Colman, M.D.
More than one-third of the adult U.S. population is obese, a proportion that has risen dramatically in the last three decades. With FDA’s recent approval of two new prescription weight loss drugs, marketed under the trade names Belviq and Qsymia, the outlook for successful drug therapies to fight our nation’s growing obesity epidemic has improved. Before these two approvals, there had not been a new weight loss drug approved by FDA in more than 13 years.
In clinical testing prior to approval, compared with lifestyle modification alone, patients treated with Belviq plus lifestyle modification had an average weight loss of about 3.5% and patients treated with Qsymia plus lifestyle modification averaged weight loss of approximately 6% to 9%. Although these results are a step in the right direction, there are a few important things to keep in mind about these products.
First, if you’re looking to lose a few pounds before going to the beach or after over- indulging on vacation, these drugs are not for you. They are not even intended for use by otherwise healthy people who are significantly overweight. Both are only intended for use in people who are obese, defined as having a body mass index (BMI) over 30, or for certain overweight patients who are not obese but have a significant health problem like diabetes, high blood pressure, or high cholesterol.
These new products have received a great deal of media attention, but one aspect of their use not highlighted by the media is that these drugs are intended for chronic use as part of a comprehensive weight loss program that includes modifications to diet and increased exercise. Obesity is a chronic disease, similar to diabetes or high blood pressure, and requires long-term treatment to help patients avoid regaining weight once a treatment program is stopped. Some patients may require long-term use of a weight loss drug in order to achieve and sustain a healthy body weight, which can be associated with significant improvements in co-morbid conditions such as diabetes and hypertension.
Another point to keep in mind is that Belviq and Qsymia are both associated with potentially serious risks, which is a key reason why they are approved by FDA only for use in obese patients whose risk from the health consequences of obesity and its related health issues outweigh the risks associated with using the drug. For instance, among other adverse effects, Qsymia can cause birth defects and Belviq can cause a dangerous chemical imbalance called “serotonin syndrome.” Doctors and patients who are considering the use of these drugs as part of an individualized weight management program must carefully consider the potential benefits and the potential risks and carefully follow the label instructions for how to use these drugs safely and effectively, including stopping use of the drugs if weight loss is not achieved.
After 13 years without a new weight loss drug on the market, Belviq and Qsymia represent new hope for many who have been struggling with obesity, and will be valuable tools in their efforts to overcome the condition. Finally, however, what may be most important to remember about these two new products is that they are not “cures” for obesity. A balanced diet, exercise and other healthy lifestyle choices will remain critical components of successfully achieving and maintaining a healthy weight.
Eric Colman, M.D., is Deputy Director of the Division of Metabolism and Endocrinology Products in FDA’s Center for Drug Evaluation and Research