The purpose of this study is to evaluate treatment in Gastroesophageal Reflux Disease (GERD) patients (aged 18~75) with endoscopically proven GERD treated with AGSPT201 Tablet.

This study is 4,8 weeks, outpatient, multicenter, randomized, double-blinded, active drug comparative, therapeutic confirmatory clinical study to evaluate the efficacy and safety of AGSPT201 in erosive esophagitis patients.

Inclusion Criteria:

• aged 18~75 years
• Patients whose esophageal lesions graded over LA A grade (The severity of lesions is classified by LA classification)
• Patients whose typical reflux symptoms such as heartburn, acid regurgitation, acid reflux and esophagus irritation during the past 3 month
• Symptoms on at least 2 days of the past 7 days

Exclusion Criteria:

• PPI treatment within 4 weeks before dosing or treatment of H2 blocker, sucralfate, prokinase NSAID (except low dose aspirin) within 2 weeks before dosing.
• Patients whose history of GI tract resection or vagotomy.
• Barrett's oesophagus greater than 3cm in length and high-grade dysplasia.
• Acid irrelevant Heartburn and regurgitation.
• Zollinger Ellison syndrome
• Hypersensitive and/or allergy to Pantoprazole and/or other PPI
• Pregnancy and lactation
• peptic ulcer
• serious hepatic
• any other renal, cardiac or haematological disease.
• Patients participated any other clinical studies during the past 3 months.