Pantoprazole effectively controls intra-oesophageal pH and promotes oesophageal healing - Further evidence for ranitidine-induced tolerance in patients with gastro-oesophageal reflux disease

Objective: The objective of this study was to compare the efficacy of pantoprazole with that of ranitidine in the control of intra-oesophageal acidity in patients with gastro-oesophageal reflux disease (GORD). Patients and Methods: Patients (n = 22; age range 30-75 years) with stage II or III CORD (Savary-Miller classification) were enrolled in a randomised. double-blind, double-dummy, parallel-group study. They were treated with pantoprazole 40mg once daily (n = 12) or ranitidine 150mg twice daily (n = 10) for 4 weeks. Intra-oesophageal 24-hour pH monitoring was performed before the study (baseline) and on days 7 and 28 of treatment. The DeMeester acid score, which takes into account the duration of reflux in the supine and upright position, as well as the number and duration of reflux episodes. was used to evaluate efficacy. Relief from symptoms was assessed on days 7 and 28; healing rates were confirmed endoscopically after 28 days of treatment. Results: Pantoprazole reduced the duration of intra-oesophageal exposure to pH below 4 over 24 hours from 6.25% at baseline to 0.15% on day 7, and to zero on day 28. In contrast, ranitidine was less effective, leading to a decrease from 4.3% over 24 hours (baseline) to 0.4% (day 7, p = 0.123) and 0.9% (day 28, p = 0.012). After 28 days of treatment. pantoprazole was superior to ranitidine in reducing the number and duration of reflux episodes and in terms of the DeMeester acid score (p less than or equal to 0.01). The effect of pantoprazole was maintained over the study period, whereas the efficacy of ranitidine declined from day 7 to day 28. Healing was observed after 28 days in 10 of 12 pantoprazole and three of 10 ranitidine recipients (p = 0.027; intention-to-treat population). There was a trend towards greater symptom relief with pantoprazole. Conclusion: Pantoprazole was superior to ranitidine, both in maintenance of intra-oesophageal pH above 4 and healing of oesophageal lesions in patients with stage II or III GORD. The efficacy of ranitidine decreased with repeated administration, indicating the development of tolerance (tachyphylaxis).