A Trial to Evaluate the Efficacy and Safety of YH12852 in Patients With Functional Dyspepsia

Inclusion Criteria: 1. Subjects must be willing and able to provide written informed consent. 2. BMI of \< 35 kg/m2 3. Patients experiencing one or more of functional dyspepsia symptoms beginning at least 6 months prior according to Rome III criteria, with the symptom(s) evident over the last 3 months at the time of screening 4. Patients with no evidence of organic lesions based on upper GI endoscopy, which could be the cause of dyspeptic symptoms 5. Women of childbearing potential (WOCBP) must have a negative pregnancy test result at the screening visit and use an adequate method of contraception to avoid pregnancy throughout the study Exclusion Criteria: 1. Women who are pregnant or breastfeeding. 2. Women with a positive pregnancy test result on enrollment or prior to investigational product administration. 3. Subjects with a history of surgery that could affect gastrointestinal motility 4. Subjects with inflammatory bowel disease 5. Clinically significant chronic infection (eg. AIDS, etc), or significant medical or psychiatric illness. 6. Serious cardiovascular disease (including QT prolongation defined as QTc interval ≥ 450msec) or respiratory disease 7. History of alcohol or drug abuse within the previous one year. 8. Subjects with mental illness (e.g. schizophrenia, dementia etc) that may render the inability to complete the study 9. Physical and Laboratory Test Findings 10. Administration of any other investigational product or participation in other clinical trials within 3 months prior to randomization.