cilansetron and Colonic-Diseases--Functional

Topics: Antidepressive Agents; Benzofurans; Carbazoles; Carbolines; Colonic Diseases, Functional; Gastrointestinal Agents; Humans; Indoles; Physical Examination; Pyridines

Cilansetron is a 5-HT3 antagonist tinder development by Solvay Pharmaceuticals as a potential treatment for irritable bowel syndrome (IBS). The compound targets non-constipated men and women with IBS. Cilansetron is being evaluated in phase III trials, but up to now, only scarce information has been made available and most publications have appeared in abstract form only. In July 2001, it was reported that regulatory submissions were expected in 2003 [416185]. Also in July 2001, after discussion with the FDA, Solvay initiated a revised phase III program in diarrhea-predominant IBS and signed a five-year 'preferred-provider' clinical services agreement with Quintiles Transnational to conduct the trial. At this time, Solvay was also seeking marketing partners for cilansetron [416185]. By October 1999, Solvay was treating cilansetron as one of its main priorities, as it represented a novel class of compound [342434]. Solvay has predicted peak sales of euro 100 m to euro 1000 m [420654].

Topics: Animals; Carbazoles; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Colonic Diseases, Functional; Female; Histamine Agonists; Humans; Male; Pyridines; Structure-Activity Relationship

The aim of this study was to establish a pathophysiologic model of irritable bowel syndrome, and then to evaluate the pharmaceutical efficacy of ramosetron, a potent serotonin 3 (5-HT(3)) receptor antagonist, and other anti-irritable bowel syndrome agents in this model. Rats stressed by a conditioned stress procedure exhibited marked prolongation of freezing time, an index of fear level, and an increase in the frequency of defecation (P<0.01). A corticotropin-releasing factor (CRF) antagonist, alpha-helical CRF, inhibited both defecation and freezing behavior, while the antidiarrheal loperamide inhibited defecation only. The 5-HT(3) receptor antagonists ramosetron, cilansetron and alosetron also inhibited defecation (ED(50) values: 0.012, 0.094, 0.078 mg/kg p.o., respectively) without affecting freezing behavior. Ramosetron showed longer-lasting effect on defecation than cilansetron. Stress also resulted in increases in both proximal and distal colonic transit rates. Ramosetron and other 5-HT(3) receptor antagonists at doses inhibiting stress-induced defecation also ameliorated both stress-stimulated colonic transit rates. These results suggest that ramosetron, as well as agents used for the treatment of irritable bowel syndrome with diarrhea, has beneficial effects against emotional stress-induced colonic dysfunction. Furthermore, this emotional stress model may be useful in evaluation of drugs to treat irritable bowel syndrome presenting with diarrhea.

Topics: Animals; Behavior, Animal; Benzimidazoles; Carbazoles; Carbolines; Colon; Colonic Diseases, Functional; Conditioning, Psychological; Corticotropin-Releasing Hormone; Defecation; Disease Models, Animal; Dose-Response Relationship, Drug; Fear; Gastrointestinal Transit; Immobilization; Irritable Bowel Syndrome; Loperamide; Male; Peptide Fragments; Pyridines; Rats; Rats, Sprague-Dawley; Receptors, Serotonin, 5-HT3; Serotonin 5-HT3 Receptor Antagonists; Serotonin Antagonists; Stress, Psychological; Time Factors; Treatment Outcome