An alprostadil analogue and human gastric secretion. A double-blind placebo-controlled study of the effects of a tablet and lyovial formulation.

The effects of single doses of 800 micrograms and 1200 micrograms of the new alprostadil analogue (prostaglandin E1 16-methyl-16-methoxy derivative) MDL 646, presented as tablet and lyovial formulations, on basal and pentagastrin-stimulated gastric acid secretion, were studied in 10 normal male volunteers using a randomised, double-blind placebo-controlled cross-over design. Compared to placebo, both doses of MDL 646 significantly decreased acid output during the basal and pentagastrin-stimulated periods. No difference between the tablet and lyovial formulations was found. Total basal output (tablet and lyovial data pooled) was reduced by 58% and 68% following 800 micrograms and 1200 micrograms MDL 646, respectively. Stimulated output was reduced to a lesser degree (15% and 27%). Inhibition of the stimulated acid secretion was observed up to 1.5 to 1.75 h after drug administration. Tolerance was good with only one subject reporting nocturnal abdominal pain following each dose of the drug and placebo.