FDA rejects weight-loss drug lorcaserin and a few others

By ACSH Staff — Oct 25, 2010
Americans may be singing the obesity blues for a while after the FDA announced Saturday that it has rejected Arena Pharmaceuticals’ weight-loss drug lorcaserin due to tumor findings in animal studies that the agency fears might indicate a risk of cancer in humans. The FDA is also set to announce by Thursday a final decision for Vivus Inc.’s weight-loss drug Qnexa, which a panel voted against by a 10-to-6 vote in July, citing safety concerns such as birth defects, depression, and an increased heart rate.

Americans may be singing the obesity blues for a while after the FDA announced Saturday that it has rejected Arena Pharmaceuticals’ weight-loss drug lorcaserin due to tumor findings in animal studies that the agency fears might indicate a risk of cancer in humans. The FDA is also set to announce by Thursday a final decision for Vivus Inc.’s weight-loss drug Qnexa, which a panel voted against by a 10-to-6 vote in July, citing safety concerns such as birth defects, depression, and an increased heart rate.

Abbott Laboratories also took a hit earlier this month when its weight-loss drug Meridia was pulled from the market due to an increased risk of cardiovascular events in patients with elevated blood pressure or known cardiovascular risk factors. “Why should we be surprised by this finding?” asks ACSH's Dr. Gilbert Ross. “Instead of pulling Meridia — one of the few effective weight-loss drugs — from the market, it should be restricted to patients who do not possess these risk factors. In fact, those exhibiting the side effects never should have been given the drug in the first place. Now, no one can use it.”

When announcing their ruling, the FDA found that the risks outweighed the “marginal” effectiveness of these weight-loss drugs.

“But what about the risks of obesity?” exclaims ACSH's Dr. Elizabeth Whelan. “Prescription Xenical and over-the-counter Alli are the only weight-loss drugs we have left, and not everyone can take them.”

Dr. Ross was also perturbed that the FDA declined lorcaserin because rodents given high doses of the drug developed tumors. “This does not in any way correlate with cancer risk in humans. This methodology of assessing carcinogenic risk is obsolete and needs to be scrapped. We said it in 2005 with our publication America’s War on Carcinogens, and we’ll keep saying it.”