The findings come from a clinical trial sponsored by Abbott, which makes Meridia. Each of the 22 medical centers participating in the study had its own weight loss program. Some were more effective than others.
But overall, Children's Hospital of Philadelphia researcher Robert I. Berkowitz, MD, and colleagues found that the 368 extremely overweight 12- to 16-year-olds in the study who took Meridia did better after one year than the 130 who took inactive placebo pills.
"The addition of [Meridia] to a behavior therapy program in our 12-month, placebo-controlled study conducted in obese adolescents ... resulted in statistically significant improvements [in body mass]," Berkowitz and colleagues report in the July 18 issue of Annals of Internal Medicine.
Indeed, the body mass index for the teens who took Meridia -- a measure of weight relative to height and the chief indicator of obesity-- dropped about 17% from the "overweight" category (the highest risk category for children and teens) to the "at risk of overweight" category.
In addition to losing weight, Meridia helped teens lose an average of more than 3 inches from their waistline. Those who took placebo pills lost less than an inch of waist circumference.
Fewer teens taking Meridia dropped out of the study -- but the dropout rate still was high. Only about three-fourths of those who got Meridia, and fewer than two-thirds of those who got placebo, finished the study.
Over the year of taking the drug, Meridia was well tolerated. Racing pulse was a little more common in those who took the drug, but study doctors did not consider this clinically significant. The drug also sometimes causes dry mouth, constipation, dizziness, and insomnia.
In an editorial accompanying the Berkowitz team's report, CDC researcher William H. Dietz, MD, PhD, notes that the findings do not address the question of whether Meridia will work for longer than one year.
And Dietz raises an important question: Who needs drug therapy for obesity? Given the fact that it's a life-long struggle to keep weight off, will teens who get short-term benefit from the drug need to continue treatment indefinitely?
"We must still carefully weigh the decision to prescribe drug therapy, because the long-term risks or benefits of drug therapy in children and adolescents are unknown," Dietz suggests. "Because drug therapy is likely to have higher lifetime risks and costs than behavioral interventions, physicians should aim for sustained behavior change and reserve drug therapy for the severely overweight adolescent who cannot otherwise lose weight."
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