BACKGROUND: The efficacy of antireflux surgery (ARS) and proton pump inhibitor therapy in the control of gastroesophageal reflux disease is well established. A direct comparison between these therapies is warranted to assess the benefits of respective therapies. STUDY DESIGN: There were 310 patients with erosive esophagitis enrolled in the trial. There were 155 patients randomized to continuous omeprazole therapy and 155 to open antireflux surgery, of whom 144 later had an operation. Because of various withdrawals during the study course, 122 patients originally having an antireflux operation completed the 5-year followup; the corresponding figure in the omeprazole group was 133. Symptoms, endoscopy, and quality-of-life questionnaires were used to document clinical outcomes. Treatment failure was defined to occur if at least one of the following criteria were fulfilled: Moderate or severe heartburn or acid regurgitation during the last 7 days before the respective visit; Esophagitis of at least grade 2; Moderate or severe dysphagia or odynophagia symptoms reported in combination with mild heartburn or regurgitation; If randomized to surgery and subsequently required omeprazole for more than 8 weeks to control symptoms, or having a reoperation; If randomized to omeprazole and considered by the responsible physician to require antireflux surgery to control symptoms; If randomized to omeprazole and the patient, for any reason, preferred antireflux surgery during the course of the study. Treatment failure was the primary outcomes variable. RESULTS: When the time to treatment failure was analyzed by use of the intention to treat approach, applying the life table analysis technique, a highly significant difference between the two strategies was revealed (p < 0.001), with more treatment failures in patients who originally were randomized to omeprazole treatment. The protocol also allowed dose adjustment in patients allocated to omeprazole therapy to either 40 or 60 mg daily in case of symptom recurrence. The curves subsequently describing the failure rates still remained separated in favor of surgery, although the difference did not reach statistical significance (p = 0.088). Quality of life assessment revealed values within normal ranges in both therapy arms during the 5 years. CONCLUSIONS: In this randomized multicenter trial with a 5-year followup, we found antireflux surgery to be more effective than omeprazole in controlling gastroesophageal reflux disease as measured by the treatment failure rates. But if the dose of omeprazole was adjusted in case of relapse, the two therapeutic strategies reached levels of efficacy that were not statistically different.