A study to look at the rates of remission (non re-appearance of erosive esomeprazole) when treated with esomeprazole or lansoprazole; in patients in with erosive esomeprazole (EE) that is in remission (i.e. previously healed EE).

Inclusion Criteria:

• Episodes of heartburn (described as a burning feeling rising from the stomach or lower part of the chest up towards the neck) for 2 days or more during the last 7 days prior to baseline
• Confirmed diagnosis of Erosive Esophagus, patients must undergo an endoscopy before entering the study.

Exclusion Criteria:

• Any signs of gastrointestinal bleeding at the time of the starting the study.
• Any previous gastric or esophageal surgery.
• Various gastrointestinal diseases as listed in the protocol.