FDA Issues New Obesity Drug Heart Warning: BioBuzz

WASHINGTON (TheStreet) -- Abbott Labs'(ABT Quote) weight-loss drug Meridia may cause a higher incident of heart-related adverse events, including heart attacks, strokes and death, than patients using a placebo, according to preliminary data flagged in an alert by the U.S. Food and Drug Administration late Friday.

The new, unexpected warning about a possibly serious side effect related to an approved weight-loss drug comes at an inopportune time for the three small drug makers -- Arena Pharmaceuticals(ARNA Quote), Vivus(VVUS Quote) and Orexigen Therapeutics(OREX Quote) -- who will soon seek regulatory approval for new obesity drugs.

Meridia is a weight-loss drug approved in 1997. As part of its post-approval commitments, Abbott has been conducting a large study of 10,000 patients to determine whether treatment with Meridia could reduce the number of heart-related adverse events compared to a placebo.

In mid-November, however, Abbott reported to regulatory agencies that treatment with Meridia was associated with an 11.4% rate of cardiovascular events compared to 10% for patients treated with placebo.

"This difference is higher than expected, suggesting that sibutramine is associated with an increased cardiovascular risk in the study population," said the FDA in its statement released Friday evening. Sibutramine is the scientific name for Meridia.

Meridia's label already comes with a warning that the drug should not be used in patients with a history of heart disease. An Abbott spokesman told Dow Jones Newswire that most of the patients in the study would not normally be prescribed Meridia because they had some form of heart disease, therefore the company doesn't believe that the safety profile of Meridia has changed.