Efficacy and Safety of EsoDuo®

Inclusion Criteria: 1. Male or Female aged ≥ 19 years 2. Patients diagnosed with non-erosive reflux disease or mild erosive reflux disease 3. Episode of heartburn the GERD symptom(either heartburn or gastric acid reflux) Exclusion Criteria: 1. Surgery history on stomach or esophagus 2. Barrett's esophagus (over 3cm), esophageal varices, esophageal stricture, esophageal achalasia, eosinophilic esophagitis, and primary motility disorders 3. Patients diagnosed with Grade C or Grade D according to the LA Classification system during upper gastrointestinal endoscopy 4. Patients with a history of malignancy within the past 5 years prior to the screening visit (Visit 1) 5. Patients who have taken prohibited concomitant medications within 14 days prior to the screening visit or require continuous administration of prohibited medications during the trial period. 6. Clinically significant Abnormal Lab test 7. Pregnant woman, Breastfeeding woman.