EQUIPOTENT INHIBITION OF GASTRIC-ACID SECRETION BY EQUAL DOSES OF ORAL OR INTRAVENOUS PANTOPRAZOLE

Background: Pantoprazole is a proton pump inhibitor characterized by a low potential to interact with the cytochrome P450 system, and linear pharmacokinetics. The recommended oral dose for treatment of acid-rel ated diseases is 40 mg. Methods: Using a randomized, crossover study d esign we compared the ability of 40 mg oral and intravenous pantoprazo le to elevate the intragastric pH in healthy volunteers (n = 20,'per p rotocol'), during two treatment phases. The duration of each phase was 5 days. Pantoprazole 40 mg was administered once daily either as a ta blet or as an intravenous injection. A 24 h pH-metry was used to recor d the intragastric pH on day 5 of each regimen; this was compared to t he baseline curve obtained before each study period. The calculated 90 % confidence intervals (90% CI) represent the mean difference in the i ntragastric pH, attained after intravenous or oral administration. The predefined equivalence range for the 90% CI was +/- 20% for the perce ntage time at which the gastric pH was at least pH 3 or 4 and +/- I un it for the median pH. Results: Pantoprazole was well tolerated during both treatment phases. The mean of the 24 h median pH was 3.3 and 3.1 for the intravenous and oral treatments, respectively; the correspondi ng differences were 0.2 (90% CI: - 0.03 to 0.44). For the mean percent age time at which the pH was 3 or above, the respective calculated val ues were 57% and 51%, with a difference between the two administration routes of only 5.7% (90% CI: 1.8 to 9.6). At an intragastric pH of 4 or above, the mean percentage time was 42% and 38% following intraveno us and oral treatment, respectively, with a difference between the tre atment routes of only 4.4% (90% CI: 0.6 to 8.3). Conclusions: These re sults imply that the two formulations of pantoprazole can be assumed t o be equipotent. Hence, the intravenous formulation of pantoprazole co uld be considered as an alternative route of administration.