The aim of this study is to compare investigator and patient-assessed gastroesophageal reflux disease symptoms in patients with erosive GERD or endoscopic-negative GERD (enGERD). An endoscopy will be performed at study start and study end. During the study, the patients will complete a patient-orientated, self-assessed reflux questionnaire (ReQuest™ questionnaire). The study duration consists of a baseline period (8 days) and treatment period (28 days). Pantoprazole (tablet) will be administered once daily at one dose level. The study will provide further data on safety and tolerability of pantoprazole.

Main Inclusion Criteria:

• Written informed consent
• Outpatients
• History of GERD-related symptoms for at least 6 months prior to study inclusion
• Endoscopically confirmed erosive GERD or non-erosive GERD

Main Exclusion Criteria:

• Acute peptic ulcer and/or ulcer complications
• PPIs during last 7 days prior to study start
• Systemic glucocorticoids or non-steroidal anti-inflammatory drugs including COX-2 inhibitors during the last 28 days prior to study start; except regular intake of acetylsalicylic acid up to a daily dose of 163 mg/day
• Intake of PPIs in combination with antibiotics for eradication of H. pylori