Conditions: Ulcerative Colitis
Keywords: Pharmacokinetics Aminosalicylates Mucosal levels Rectal dialysis
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 2
Healthy volunteers: yes

Brief summary:
The investigators plan to develop a novel method of estimating 5-ASA levels in the rectum at a mucosal level using in vivo rectal dialysis technique towards the eventual goal of determining the optimal dosing of Asacol® that would provide therapeutic levels of 5-ASA in the left colon.

Detailed description:
Asacol® is mesalazine in a pH-dependent tablet (Eudragit S) that remains intact until reaching the terminal ileum. The tablet dissolves at a pH 7 or greater, allowing mesalazine release in the terminal ileum and throughout the colon; hence, it would be anticipated that this form of 5-ASA will produce higher concentrations in the left colon in patients with active ulcerative colitis compared to other immediate release forms of 5-ASA. However, preliminary research using dynamic computer modeling and simulation predicted that patients with active ulcerative colitis (characterized by an increased stool frequency) treated with Asacol® and Lialda (another delayed release formulation) will achieve very low 5-ASA levels in the sigmoid colon and rectum. The model predicts that these 5-ASA preparations will be relatively ineffective in treating the left side of the colon in active ulcerative colitis.

Arms:
arm 1: Rectal dialysis will be done after 1 week on 1200 mg asacol arm 2: Rectal dialysis will be done after 1 week on 2400 mg asacol

Interventions: intervention 1: Rectal dialysis intervention 2: Rectal dialysis
Intervention descriptions: intervention 1: Rectal dialysis done after 1 week on either 1200/2400 mg Asacol dose to test rectal mucosal 5-ASA levels intervention 2: Rectal dialysis done after 1 week on either 1200/2400 mg Asacol dose to test rectal mucosal 5-ASA levels

Protocol document: