Acid suppression in healthy subjects following lansoprazole or pantoprazole

AIM: To compare the effect of lansoprazole, 30 mg once daily, with that of pantoprazole, 40 mg once daily, for the inhibition of gastric acid secretion. METHODS: Two randomized, single-blind, two-way, crossover studies were conducted in 74 healthy male volunteers. Lansoprazole, 30 mg, or pantoprazole, 40 mg, was administered once daily for five consecutive days with at least a 2-week washout period between regimens. Ambulatory 24-h intragastric pH was recorded at baseline and on days 1 and 5 of each crossover treatment period. RESULTS: On day 1 in both studies, lansoprazole, 30 mg, produced significantly higher mean 24-h intragastric pH values when compared to pantoprazole, 40 mg (3.78 vs. 3.08, P < 0.001, and 3.97 vs. 3.20, P < 0.001, in the first and second studies, respectively). In both studies, lansoprazole, 30 mg, produced significantly greater proportions of time that the intragastric pH was above 3, 4 and 5 when compared with pantoprazole, 40 mg (P < 0.005 in all comparisons). By treatment day 5 in the first study, lansoprazole, 30 mg, continued to produce a higher mean 24-h intragastric pH (4.15 vs. 3.91, P=0.014) and a significantly greater percentage of time that the intragastric pH was above 4 (63% vs. 56%, P=0.017) and 5 (41% vs. 30%, P < 0.001) when compared with pantoprazole, 40 mg. In the second study, the effects on intragastric pH were comparable between the two treatment groups. Headache was the most commonly reported adverse experience (nine lansoprazole-treated subjects, seven in the first study and two in the second study; six pantoprazole-treated subjects, five in the first study and one in the second study). CONCLUSIONS: Lansoprazole, 30 mg once daily, produces a faster onset and greater degree of acid inhibition than pantoprazole, 40 mg once daily. The implications for these differences on symptom relief and healing of erosive oesophagitis should be explored.