Inclusion criteria:

For inclusion in the study the subject must fulfill all of the following criteria:

1. Patients aged between 18 and 70 years.
2. Chronic symptoms (>8 weeks) suggestive for GERD, as defined in Table 2 with or without reflux esophagitis grade A-D (Los Angeles classification)
3. Indication for endoscopy due to GERD symptoms is given
4. Written informed consent

Table 2: Lead GERD criteria

For inclusion in the study, all of the following lead GERD criteria should hold:

• At least one of the symptoms heartburn or regurgitation.
• At least 8 weeks ongoing symptoms.
• At least 3 times a week.
• At least moderate intensity, corresponding to light impairment in daily life and occasional need for drugs.

Exclusion criteria:

Any of the following is regarded as a criterion for exclusion from the study:

1. Severe organic esophageal disease other than reflux esophagitis (e.g. carcinoma, esophageal stenosis).
2. Gastric or duodenal ulcers
3. Patients with visible Barrett's mucosa; no histological confirmation is required for exclusion
4. History of previous esophageal or gastric surgery
5. Alcohol or drug abuse
6. Severe organic or psychiatric disease
7. Pregnancy or lactation
8. Women with child-bearing potential if no medically accepted contraceptive measures are used
9. Contra-indication to amoxicillin, clarithromycin or esomeprazole (Nexium)
10. Need for concomitant medication which could interfere with the investigational products (substrates of CYP3A4)
11. Suspected or confirmed poor compliance
12. Participation in a clinical study within 8 weeks prior to enrollment.