Adults with obesity who received Novo Nordisk’s diabetes drug Victoza (liraglutide) lost significantly more weight than those receiving Roche’s Xenical (orlistat), according to the

 results of a study published in The Lancet. The researchers said the data show Victoza, which is approved in Europe to treat type 2 diabetes, may offer “a new mode of action for the treatment of obesity and improved efficacy compared with” current therapies.

In the trial, 564 patients without type 2 diabetes who had a body mass index of between 30 and 40 were randomised to receive one of four once-daily Victoza doses, Xenical three times daily, or placebo. The volunteers also undertook a daily exercise regimen and reduced their daily calorie intake by 500 calories.

After 20 weeks, results showed that the mean weight loss for those receiving Victoza was 4.8 kilograms to 7.2 kilograms, compared to 4.1 kilograms with Xenical and 2.8 kilograms with placebo. In addition, 76 percent of subjects receiving the highest dose of Victoza lost more than 5 percent of their body weight, compared to 44 percent receiving Xenical and 30 percent on placebo. Victoza also reduced blood pressure at all doses tested, and led to a decrease in the prevalence of prediabetes at the three highest doses examined.

In an accompanying editorial in The Lancet, George Bray questioned “whether long-term use of an injectable drug is palatable as a treatment for obesity,” but remarked that GLP-1 agonists, such as Victoza, will fulfill “their promise for the treatment of obesity.” In response to the study, GlaxoSmithKline, which markets a lower-dose over-the-counter version of orlistat as alli, said the comparison between the products was "not fair" because of their different methods of delivery and the fact that only one dose of Xenical was used in the study.