The effects of orlistat on body weight and glycaemic control in overweight patients with type 2 diabetes: a randomized, placebo-controlled trial.

AIM: To assess the long-term effects of orlistat on body weight, glycaemic control and cardiovascular risk factors in overweight patients with type 2 diabetes.

METHODS: This was a multicentre, randomized, placebo-controlled study with a 4-week placebo plus diet lead-in period and a 48-week, double-blind treatment period. Overweight or obese adults [body mass index (BMI) >or= 28 kg/m2] with HbA1c of 6.5-11% and clinical type 2 diabetes were randomized to orlistat (120 mg t.i.d. n = 189) or placebo (n = 180) in conjunction with a low-calorie diet. Patients had either received sulphonylurea therapy for at least 2 months before the study or were not receiving any antidiabetic medication (the majority of which were drug-naïve).

RESULTS: After 1 year, patients in the orlistat group lost significantly more weight than patients in the placebo group (-5.4% vs. -3.6%; p = 0.006). Moreover, significantly more patients achieved weight loss of >or= 5% with orlistat compared with placebo (51.3% vs. 31.6%; p = 0.0001). Patients treated with orlistat also had significantly greater improvements than placebo-treated patients in HbA1c (-0.9% vs. -0.4%; p < 0.001), fasting glucose (-1.6 vs.-0.7 mmol/l; p = 0.004) and post-prandial glucose (-1.8 vs. -0.5 mmol/l; p = 0.003). In addition, orlistat-treated patients had a significantly greater reduction in LDL cholesterol compared with placebo. Overall, orlistat had a similar safety profile to placebo, with the exception of a higher incidence of generally mild and transient gastrointestinal events known to be associated with the mode of action of orlistat.

CONCLUSIONS: Treatment with orlistat plus diet resulted in significant weight loss, improved glycaemic control and cardiovascular risk factor profile in overweight patients with type 2 diabetes.