The purpose of this study, conducted academic Pilot research purposes, this is not clear as to permit. when orlistat to sibutramine merge if there are additional effects of BMI and group, which has an attribute that is greater for the combined effect is to analyze.

• Study phase: Investigator-initiated clinical study (Pilot study)
• Method of blinding: Double-blind
• Control: Placebo-controlled
• Assignment method: Randomization (Sibutramine monotherapy group: Orlistat and Sibutramine combination group = 1 : 1)
• Studied disease: Obesity
• Study population: Subjects eligible for inclusion/exclusion criteria
• Dosing period: Total 18 weeks Run-in period (2 weeks), dosing period (12 weeks) and post-dosing observation period (4 weeks)

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.

MAOInclusion Criteria:

1. A patient who gave one's voluntary written consent to participate in this clinical study
2. Aged ≥ 18 and < 50 years old
3. An obese patient with a body mass index (BMI) ≥ 27 kg/m2
4. In case of a women, premenopausal woman

Exclusion Criteria:

1. A patient with the weight change ≥ 5% over the past 3 months
2. A patient who was receiving a MAO(monoamine oxldase) inhibitor within 1 months of screening
3. A patient with an active acute or chronic disease at the participation of the study
4. A patient with the malignancy history within the past 5 years
5. A patient diagnosed with secondary obesity (Cushing's syndrome, thyroid disease, etc.)
6. A patient with a significant cardiovascular disease (coronary vascular disease, congestive heart failure, peripheral arterial obstructive disease, arrhythmia, cerebrovascular disease, etc.), poorly controlled hypertension defined by JNC(Joint National Committee) 7 guidelines, diabetes, severe hepatic/renal disease and CNS(Central Nervous System) disease, drug abuse, psychiatric disorder, positive prostatic hyperplasia concurrent with urinary retention and glaucoma within the past 1 year according to medical records
7. A patient falling under the followings from screening test results Hemoglobin < 10g/L or platelets < 100* 103/μL Total bilirubin > 2.0mg/dL Serum GOT(Glutamate oxaloacetate transaminase) or GPT(glutamic pyruvate transaminase) > 120 IU/L Serum creatinine > 1.4mg/dL Serum uric acid > 10mg/dL Thyroid stimulating hormone < 0.1μIU/mL or > 6.5 μIU/mL
8. A patient with clear unexplained abnormal findings in chest X-ray, urinalysis, electrocardiogram
9. A pregnant women or breastfeeding mother
10. A patient participating in another clinical study other than this study
11. Other patient who is legally and mentally not appropriate to participate in a clinical study, at the judgment of the investigator
12. A person who participated in other clinical study within the past 3 months