Orlistat in the Long-term Treatment of Obesity in Primary Care Settings

Objective: To evaluate the long-term efficacy and tolerability within primary care settings of orlistat, a gastrointestinal lipase inhibitor, for the treatment of obesity.

Design: Randomized, double-blind, placebo-controlled, multicenter study.

Participants: A group of 796 obese patients (body mass index, 30-44 kg/m2), treated with placebo 3 times a day (TID), 60 mg of orlistat TID, or 120 mg of orlistat TID, in conjunction with a reduced-energy diet for the first year and a weight-maintenance diet during the second year.

Setting: Seventeen primary care centers in the United States.

Main Outcome Measures: Changes in body weight and obesity-related disease risk factors.

Results: Patients treated with orlistat lost significantly more weight (7.08 +/- 0.54 and 7.94 +/- 0.57 kg for the 60-mg and 120-mg orlistat groups, respectively) than those treated with placebo (4.14 +/- 0.56 kg) in year 1 (P<.001) and sustained more of this weight loss during year 2 (P<.001). More patients treated with orlistat lost 5% or more of their initial weight in year 1 (48.8% and 50.5% of patients in the 60-mg and 120-mg groups, respectively) compared with placebo (30.7%; P<.001), and approximately 34% of patients in the orlistat groups sustained weight loss of 5% or greater over 2 years compared with 24% in the placebo group (P<.001). Orlistat produced greater improvements than placebo in serum lipid levels and blood pressure and was well tolerated, although treatment resulted in a higher incidence of gastrointestinal events.

Conclusions: This long-term study indicates that orlistat is an effective adjunct to dietary intervention in the treatment of obesity in primary care settings.