1. Home>
2. Specialties>
3. General Medicine>
4. Summary and Comment

Orlistat, a New Drug for Weight Reduction.

Orlistat is a new weight-reducing drug that works by inhibiting gastrointestinal lipases and lowering fat absorption. Two double-blind, randomized trials supported by the manufacturer tested an oral dose of 120 mg three times daily.

A European multicenter group compared orlistat with placebo in 688 obese persons on a hypocaloric diet. At one year, average weight loss was significantly greater with orlistat (10.3 vs. 6.1 kg with placebo); 39 percent of the orlistat patients lost more than 10 percent of initial bodyweight, versus 18 percent of those on placebo. All subjects were again randomized to orlistat or placebo and advanced to a eucaloric (weight maintenance) diet for a second year of study; orlistat was more effective in preventing regain of weight than placebo. Those receiving placebo after orlistat steadily regained most of the weight lost on orlistat.

In a U.S. study of 322 obese patients with type 2 diabetes, orlistat-treated patients lost significantly more weight on a mildly hypocaloric diet than placebo recipients (mean, 6.2 vs. 4.3 kg) after one year. They also had modest but significant improvements in fasting glucose and glycohemoglobin levels.

Comment: Taking orlistat for one to two years promoted moderate weight loss in nondiabetic and diabetic patients. Gastrointestinal side effects were common in both trials, but only about 4 percent of subjects reportedly withdrew for this reason. The drug also reduced serum levels of fat-soluble vitamins in some patients. Orlistat is under consideration by the FDA, which is currently examining follow-up safety data.

— AS Brett

Published in Journal Watch General Medicine August 21, 1998

Citation(s):

Sjostrom L et al. Randomised placebo-controlled trial of orlistat for weight loss and prevention of weight regain in obese patients. Lancet 1998 Jul 18 352 167-173.

• Medline abstract (Free)

Hollander PA et al. Role of orlistat in the treatment of obese patients with type 2 diabetes: A 1-year randomized double-blind study. Diabetes Care 1998 Aug 21 1288-1294.

• Medline abstract (Free)

2011 Year in Review