Two drugs approved in 2012 to treat obesity have hardly become big sellers. That’s partly because of the cost and spotty insurance coverage. A month’s supply for phentermine-topiramate (Qysmia) is about $160 and the cost for lorcaserin (Belviq) is about $200.
But it may also be attributable to the drugs’ modest effectiveness and safety concerns, according to two Dartmouth researchers who wrote a column in JAMA Internal Medicine warning about the drugs’ unknown health risks.
“Neither medication is marketed in Europe because of safety concerns,” wrote column authors Drs. Steven Woloshin and Lisa Schwartz, family medicine physicians at the Dartmouth Institute for Health Policy and Clinical Practice in Lebanon, N.H.
They’re referring to uncommon side effects seen in clinical trials that are listed on the drugs’ labels, including memory loss, attention difficulties, language problems, and depression. Both also cause low blood sugar in those on medication for type 2 diabetes.
In deciding to OK the drugs, the US Food and Drug Administration determined that the health problems associated with being obese outweigh the drugs’ risks. But the agency also required that the manufacturers continue to conduct safety trials.
Woloshin and Schwartz wrote that these “safety trials are behind schedule” and “until there is more convincing evidence about the cardiovascular safety of these drugs, physicians and patients should approach them cautiously.”