seems to be a 5HT4 selective agonist? Alizyme is developing renzapride for the treatment of irritable bowel syndrome (IBS) and had successfully completed a 510 patient Phase IIb clinical trial in constipation-predominant IBS (c-IBS) patients. A separate 160 patient Phase IIb clinical trial in mixed-symptom IBS (m-IBS) patients has successfully completed enrolment and is expected to report preliminary results in October 2003. In addition, a 48 patient pharmacokinetic/pharmacodynamic study is currently ongoing at Mayo Clinic in the USA in c-IBS patients. Renzapride has both 5-HT4 agonist and a 5-HT3 -antagonist activity. These receptors influence intestinal motility and sensitivity. The dual mechanism of action of renzapride gives it a distinctive pharmacology and distinguishes it from its potential competitors. Renzapride was initially discovered at Beecham Research Laboratories. Following a development agreement with SmithKline Beecham, Alizyme gained full ownership of renzapride due to SmithKline Beecham's merger with GlaxoWellcome.In a Phase IIa clinical trial in c-IBS patients, which was completed by Alizyme in 2000, improvements in symptoms occurred with renzapride in both male and female patients.The Phase IIb clinical trial provided a successful demonstration of efficacy and safety. There was an efficacy profile across a range of c-IBS symptoms quantitatively and qualitatively similar to that of tegaserod (Novartis' Zelmac�/Zelnorm�), the only drug currently approved for these patients. IBS is suffered by approximately one in five adults at some stage in their life and is the most common reason for referral to gastroenterologists. The cause of IBS is not known but the symptoms include abdominal pain and discomfort, abdominal bloating, and constipation and/or diarrhoea. Three main groups of IBS sufferers are recognised: Constipation-predominant (c-IBS) Diarrhoea-predominant (d-IBS) Mixed symptoms (m-IBS) in which patients alternate between episodes of constipation and diarrhoea. Bada