Regulators in the USA and Europe are reviewing preliminary data which suggests that patients taking Abbott Laboratories’ obesity drug Meridia have a higher number of cardiovascular events.

The European Medicines Agency’s Committee for Medicinal Products for Human Use has started a safety review of anti-obesity medicines containing Meridia (sibutramine), sold in Europe as Reductil, Zelium, Reduxade, based on data coming from the SCOUT study which investigates long-term cardiovascular effects of the drug in a population with high cardiovascular risk. The review was triggered by Germany and the CHMP will “assess the impact of the new data on the benefit-risk balance of these medicines and make a recommendation whether their marketing authorisations should be maintained, changed, suspended or revoked”.

Across the Atlantic, the US Food and Drug Administration is also looking at whether use of Meridia increases the likelihood of heart attack, stroke, resuscitated cardiac arrest or death compared to placebo. The agency insisted that it is making no conclusions about the preliminary findings at this time, but said that they highlight the importance of avoiding the use of sibutramine in patients with a history of coronary artery disease, congestive heart failure, arrhythmias, or stroke, as recommended in the current Meridia labelling.

Abbott notes that sibutramine is approved for patients who are obese but have no history of cardiovascular disease and 90% of patients in the SCOUT study, begun in 2003 in response to a request by the EMEA in 2003, do not belong to the group for which Meridia is permitted. The company is reviewing the data, but does not believe that they show any need for a change in the safety profile of the drug when it is used in the approved patient population.