Assess the Additional Weight Loss Effect of Orlistat Used in Combination With Sibutramine

After the screening period, patients eligible for inclusion/exclusion criteria would administer Sibutramine placebo and Orlistat placebo during 2 weeks of the run-in period, Subsequently, subjects are randomized to 2 groups of the Sibutramine monotherapy group and the Orlistat and Sibutramine combination group. Sibutramine monotherapy group would receive Sibutramine 10mg once daily and Orlistat placebo three times daily for 12 weeks; the Orlistat and Sibutramine combination group would receive Sibutramine 10mg once daily and Orlistat 120mg three times daily for 12 weeks. After completing the dosing period, the occurrence of adverse events would be checked for 4 weeks and the study would be completed. Body weight, abdominal CT(Computed Tomography)(visceral fat examination), body fat analysis, etc. would be measured before the study initiation and after 14 weeks of treatment, and comparatively analyzed. A two sample t-test is conducted for the inter-group comparison and a paired t-rest is conducted for the comparison between baseline and after 14 weeks after the study initiation.