PHOENIX — Sibutramine helped people who had lost substantial amounts of weight maintain much of their weight loss for 2 years in a multicenter, double-blind, randomized trial. By 3 years, however, they had regained about as much as a control group on placebo.
In all, 466 participants started the maintenance study after losing an average of 30 kg in nonpharmacologic weight-loss programs. Although they all had begun to put the pounds back on before entering the trial, they had to have maintained at least half of their peak weight loss for 6 months to be eligible.
“The placebo group steadily gained weight throughout the study. The sibutramine group gained less weight,” Dr. James W. Anderson, the principal investigator, reported in an analysis at the annual meeting of The Obesity Society.
Indeed, the net weight gain for the two groups was significantly less with sibutramine (Meridia) for the first 2 years—0.6% vs. 3.1% at 6 months, 2.8% vs. 5.6% at 1 year, and 7.1% vs. 9.8% at 24 months. At 3 years, the sibutramine group still had less net weight gain (9.6% vs. 11.7%), but the difference was no longer statistically significant, and both groups appeared to plateau with no difference from 30 to 48 months.
Dr. Anderson, professor emeritus of medicine and clinical nutrition at the University of Kentucky, Lexington, has been medical director of the HMR Weight Loss Program at the university for 22 years. He said he proposed the study to address the common problem of weight rebound after weight loss and designed the trial to run for 60 months.
Abbott Laboratories became the study sponsor after acquiring sibutramine and decided to curtail follow-up at 36 months, Dr. Anderson said. He emphasized that he has not received any financial support from Abbott for more than 5 years.
The trial randomized 236 subjects to receive 15 mg of sibutramine per day and 230 to placebo at 26 sites. Of these, 150 placebo patients and 144 sibutramine patients completed 36 months.
The baseline population was about 48 years old on average. More than 90% were white, and three-fourths were women. The participants weighed about 91 kg with a mean body mass index slightly over 32 kg/m
With data on 289 participants, Dr. Anderson estimated that they would have maintained 10.4 kg of weight loss at 5 years—or 35.1% of their initial weight loss before entering the trial.
Blood pressure and pulse rate were significantly higher with sibutramine, said Dr. Anderson, but total adverse events were not. “Sibutramine may be a useful adjunct in selected patients,” he concluded.
'The placebo group steadily gained weight…. The sibutramine group gained less weight.' DR. ANDERSON