Weight loss drug Belviq might cause cancer, FDA warns

Federal regulators are warning the public of a possible increased risk of cancer in taking the weight-loss drug Belviq.

Results from a clinical trial “show a possible increased risk of cancer” with the prescription medication known in generic form as Lorcaserin, according to an alert issued Tuesday by the U.S. Food and Drug Administration.

Those taking the drug should talk to their doctors, advised the FDA, which is still evaluating the findings it currently views as inconclusive.

A trial involving about 12,000 participants over five years found “more patients taking Lorcaserin were diagnosed with cancer compared to patients taking placebo, which is an inactive treatment,” stated the FDA, which approved the drug in 2012. “We are continuing to evaluate the clinical trial results and will communicate our final conclusions and recommendations when we have completed our review.”

Manufactured by Eisal Inc., the U.S. subsidiary of Japan’s Eisal Co. Ltd, Lorcaserin is billed as helping obese and overweight people shed pounds by reducing the hunger pangs that prompt some to ditch diets.

Touted as a “holy grail” in the fight against obesity after a 2018 study yielded promising results, the appetite suppressant works by stimulating brain chemicals that make its users feel more full. But the headlines overhyped the drug, according to the U.K.’s National Health Service fact-checking service, which noted the study found “a small amount of weight loss” over a period of 40 months.

“Patient safety is Eisai’s priority and we will continue to work closely with the FDA to evaluate the clinical trial results,” a spokesperson for the drug maker emailed CBS MoneyWatch on Wednesday.

“We recommend patients speak directly with their health care professional in order to make the best decision about their medical treatment,” the Eisai spokesperson added. “As indicated in the FDA’s communication, at this time, the FDA and Eisai cannot conclude that Belviq increases the risk of cancer.”

First published on January 15, 2020 / 1:52 PM

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