Dose-dependent gastrointestinal effects of the somatostatin analog lanreotide in healthy volunteers.

Objective To investigate the gastrointestinal effects of intravenous lanreotide. Methods Twenty healthy male subjects participated in 2 subsequent placebo-controlled, double-blind crossover studies. The effects of 3 doses of lanreotide (50, 100, and 200 μg/h) were investigated on 24-hour intragastric acidity (study I), food-stimulated gallbladder contraction, and plasma cholecystokinin release (study II). Results Lanreotide showed linear pharmacokinetics. It raised median intragastric pH significantly and in a dose-dependent manner: from 1.4 ± 0.2 (placebo) to 2.5 ± 0.8 (P < .002) during administration of 50 μg/h lanreotide, to 3.2 ± 0.7 (P < .001) during 100 μg/h lanreotide, and to 4.3 ± 0.7 (P < .001) during 200 μg/h lanreotide. However, no significant inhibition of gastrin secretion could be established. All doses completely inhibited postprandial gallbladder contraction. Conclusion Intravenous administration of lanreotide at rates applied in this study was able to significantly inhibit intragastric acid secretion and postprandial gallbladder contraction; under these conditions few untoward effects were noted. Clinical Pharmacology & Therapeutics (1999) 65, 413–419; doi: