Regulators in Europe have recommended the suspension of Abbott Laboratories’ obesity treatment sibutramine based on its links to an increased risk of cardiovascular events and the company has accepted the decision.

The European Medicines Agency has completed a safety review initiated in November looking at sibutramine, sold as Reductil, Reduxade and Zelium in Europe and Meridia in the USA. Now, the agency has decreed that “the risks of these medicines are greater than their benefits”.

The review was prompted by data from the SCOUT study which investigated long-term cardiovascular effects of sibutramine in 10,000 patients, enrolled for up to six years, with high cardiovascular risk. The findings have shown “an increased risk of serious, non-fatal cardiovascular events, such as stroke or heart attack, with sibutramine compared with placebo”, the EMEA says.

The agency’s Committee for Medicinal Products for Human Use added that weight loss achieved with the drug “is modest and may not be maintained after stopping”. It has therefore recommended the suspension of marketing authorisations across the European Union to the European Commission for a final decision.

The need for such a decision seems arbitrary now as late last night, Abbott said it will suspend European sales. However, Eugene Sun, vice president of global pharmaceutical R&D, said “we believe there are many patients who benefit from sibutramine and respectfully disagree with the committee's opinion”. Nevertheless, he added, “we will act promptly to comply with the…recommendation."

No suspension in USA but stronger warning
Meantime in the USA, the Food and Drug Administration says Abbott has agreed to add a stronger warning to the label that states the drug should not be used in patients with a history of cardiovascular disease. The agency will hold a public advisory committee meeting once it completes its review of SCOUT and Abbott is expected to submit the full results in March. Australia's Therapeutic Goods Administration has taken a similar action.