Preliminary findings of an ongoing postmarketing clinical trial designed to evaluate the risk-benefit profile of the weight-loss drug sibutramine (Meridia) indicate that the drug may actually increase rather than decrease the risk of cardiovascular events (see http://bit.ly/7qCgQl). Approved by the Food and Drug Administration (FDA) in 1997 for the management of obesity, sibutramine inhibits the reuptake of norepinephrine, serotonin, and dopamine. The trial, entitled Sibutramine Cardiovascular Morbidity/Mortality Outcomes in Overweight or Obese Subjects at Risk of a Cardiovascular Event (SCOUT), was designed to evaluate the potential benefits of weight management on cardiovascular outcomes in approximately 10,000 patients 55 years of age or older who were overweight or obese and had a history of either heart disease or type 2 diabetes and one other cardiovascular risk factor. Patients who had suffered from a recent myocardial infarction or stroke, or who had uncontrolled heart failure, were excluded from the study. In addition to taking either sibutramine or a placebo, study participants followed a lifestyle intervention program involving diet and exercise. The preliminary findings show that 11.4% of patients receiving sibutramine experienced a cardiovascular event (myocardial infarction, stroke, resuscitated cardiac arrest, or death), compared with 10% of those who received placebo.

Sibutramine labeling has always stated that its use should be avoided in patients with a history of coronary artery disease, congestive heart failure, arrhythmia, or stroke. The preliminary clinical trial findings appear to confirm that those precautions should be strictly followed. Although no change has been made to the sibutramine labeling at this time, the FDA is conducting an expedited safety review of the drug. NPs who prescribe sibutramine should carefully evaluate the risks and benefits of its use in each patient, and inform patients of these early findings. Adverse events associated with sibutramine use should be reported to the FDA MedWatch program at https://www.accessdata.fda.gov/scripts/medwatch/medwatch-online.htm.