Null hypothesis: Change in weight from baseline to week 52 = 0 Alternative hypothesis: Change in weight from baseline to week 52 ≠ 0 The sample size calculation was based on the statistical hypotheses. Using a two-sided Wilcoxon signed-rank test with significance level 0.05 and power 80%, a sample size of 36 is needed to detect a weight change from baseline to week 52 of 0.5 standard deviation, which corresponds to a medium effect size according to Cohen. To account for drop-outs 50 patients will be enrolled in the study