A Double-Blind, Placebo-Controlled Trial to Evaluate the Safety and Tolerability of Oral Once-Daily Prucalopride (R108512) Solution in Constipated Elderly Subjects Living in a Nursing Facility

This is a multicenter, Phase II, dose-escalation trial with a 4 week double-blind, placebo-controlled treatment period. There will be four treatment cohorts (0.5 mg, 1 mg, 2 mg, or 4 mg) with 25 subjects in each. The first cohort of 25 subjects will be randomly assigned to receive either 0.5 mg R108512 or placebo in a 4 to 1 ratio, respectively, for four weeks. After two weeks of treatment, the safety and tolerability of this dose will be evaluated for each subject by an independent (external) safety committee. If, at the completion of treatment, the safety committee grants approval to proceed to a higher dose, the second cohort will be randomly assigned to receive either 1 mg R108512 or placebo for four weeks. In a likewise manner, each dose will be evaluated for safety and tolerability before the next cohort will be treated with a higher dose. No subject can participate in more than one treatment cohort.

Subjects will be instructed not to change their diet or lifestyle during the trial. Subjects will be allowed to continue the use of routine stool softeners and fiber supplements during the trial; however, all existing stimulant or osmotic laxative medication will be withdrawn. If, during the trial, the subject does not have a complete bowel movement for three or more consecutive days, he/she will be allowed the use of his/her usual stimulant or osmotic laxative or an enema as a rescue medication. No laxatives or enemas should be used within the 24 hours before and 24 hours after the start of double-blind treatment.