What benefits of Alli have been shown in studies?

Because Alli is based on another medicine containing the same active substance already authorised in the European Union (Xenical 120 mg capsules), some of the studies involved patients who took Xenical.

Alli capsules have been studied in three main studies. Two of the studies, involving a total of 1,353 overweight or obese patients with a BMI of 28 kg/m2 or more and lasted from one to two years, comparing Alli given at different doses with placebo (a dummy treatment), in combination with dieting. Neither the patients nor the doctors knew which treatment each patient was taking until the end of the study. The third study compared Alli with placebo in 391 overweight patients with a BMI between 25 and 28 kg/m2. The study lasted four months.

In all of the studies, the main measure of effectiveness was the change in weight.

The company also carried out studies to show that Alli 27 mg chewable tablets have the same effect on fat absorption as Alli 60 mg capsules.