Continuous intragastric pH monitoring in the evaluation of ebrotidine, cimetidine and placebo on gastric acidity in healthy volunteers

This study was conducted to determine the efficacy and tolerance of ebrotidine (N-[(E)-[[2-[[[2-[(diaminomethylene)amino]-4-thiazolyl) methyl]thio]ethyl]amino]methylene]-4-bromo-benzenesulfonamide, CAS 100981-43.9, FI-3542), a new H2-receptor antagonist, on reducing gastric acidity after a single 800 mg dose, compared with cimetidine 800 mg once daily and placebo by means of a continuous intragastric pH monitoring.

A total of 30 healthy volunteers were allocated to receive in a double blind, parallel design the study medication. Clinical observations, physical examinations and visual analogue scales (VAS) were performed during the study to assess the tolerability of the three treatments. Ebrotidine and cimetidine caused a greater and longer-lasting gastric acid inhibition than placebo. With ebrotidine, significantly (p < 0.05) higher median pH values (and interquartile range, IQR) were reached in the post-administration (2.61, IQR 2.02-3.93), postprandial (3.38, IQR 2.82-3.91) and nocturnal (2.83, IQR 1.69-3.77) periods than with placebo: 1.82 (IQR, 1.66-2.09), 2.81 (IQR, 2.02-3.28), and 1.89 (IQR, 1.44-2.13), respectively. Cimetidine showed significant differences compared to placebo in the post-administration (2.36, IQR 1.89-3.46) and nocturnal (2.46, IQR 1.88-4.33) periods. No statistical differences were observed between the active treatments. Ebrotidine caused a significantly higher percentage of time above pH 2.0 in the post-administration and nocturnal periods compared to placebo (p < 0.05), and above pH 3.0 in the post-administration, postprandial and nocturnal periods.

No serious adverse effects, or disturbances in the VAS or in the vital signs were reported, and all medications were well tolerated. It is concluded that a single dose of ebrotidine 800 mg is as effective as cimetidine 800 mg in reducing total and nocturnal intragastric acidity.

The study also confirms the excellent safety profile of the new drug.

CITATION  Arzneimittelforschung. 1997 Apr;47(4A):539-44