Preliminary results from a large study involving  Meridia, Abbott Labs’ popular prescription weight loss medication, have indicated that the drug  may be associated with a higher risk of  heart-related side-effects.  The findings prompted the  U.S. Food & Drug Administration (FDA) issued a Meridia Early Communication over the weekend.

Because of the serious nature of the issue, the FDA said it is conducting an expedited safety review of Meridia.  The agency will communicate its findings to the public as soon as this review is complete.

In the meantime, the FDA reiterated the importance of avoiding the use of  Meridia in patients with a history of heart disease, congestive heart failure, arrhythmias, or stroke, as recommended in the drug’s current labeling.  The agency also advised that  healthcare professionals should continue to evaluate the benefits and risks of Meridia, taking into account individual patient medical histories. Patients should talk to their healthcare professional about whether Meridia is right for them, the FDA said.

The study that prompted the Meridia Early Communication is called Sibutramine Cardiovascular Morbidity/Mortality Outcomes in Overweight or Obese Subjects at Risk of a Cardiovascular Event (SCOUT).   SCOUT, which began in 2002 was designed to show that weight loss with Meridia and standard care was more effective in reducing the number of cardiovascular events compared to weight loss from a placebo and standard care. The study involved approximately 10,000 patients who were 55 years of age or older, overweight or obese, and had a history of heart disease or type 2 diabetes plus one additional cardiovascular risk factor. Patients who recently had a heart attack or stroke, or had poorly controlled congestive heart failure were not included in the study.

In the Early Communication, the FDA said it was recently made aware that the preliminary analysis of SCOUT’s primary endpoint suggests that patients using Meridia experienced a higher number of cardiovascular events compared to those using a placebo. The preliminary data shows that cardiovascular events were reported in 11.4% of patients using Meridia compared to 10% of patients using a placebo. According to the FDA Early Communication, this difference is higher than expected, suggesting that Meridia is associated with an increased cardiovascular risk in the study population.

Meridia was approved by the FDA in 1997 for the management of obesity, including weight loss and maintenance of weight loss, in conjunction with a reduced calorie diet.  It  is only recommended for obese patients with an initial body mass index (BMI) ≥ 30 kg/m2, or BMI ≥ 27 kg/m2 with other risk factors (e.g., diabetes, high cholesterol, controlled high blood pressure).