Efficacy and safety of alosetron in women with irritable bowel syndrome: a randomised, placebo-controlled trial.
BACKGROUND
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder with symptoms of abdominal pain, discomfort, and altered bowel function. Antagonists of the type 3 serotonin receptor (5-HT3) have shown promising results in the relief of IBS-associated symptoms. We aimed to confirm these findings by doing a randomised, placebo-controlled trial.


METHODS
We studied 647 female IBS patients with diarrhoea-predominant or alternating bowel patterns (diarrhoea and constipation). 324 patients were assigned 1 mg alosetron and 323 placebo orally twice daily for 12 weeks, followed by a 4-week post-treatment period. Adequate relief of abdominal pain and discomfort was the primary endpoint; secondary endpoints included improvements in urgency, stool frequency, and stool consistency. Analysis was by intention to treat.


RESULTS
79 (24%) of patients in the alosetron group and 53 (16%) in the placebo group dropped out. The difference in the drop-out rate between groups was mainly due to a greater occurrence of constipation in the alosetron group. A greater proportion of alosetron-treated patients than placebo-treated patients (133 [41%] vs 94 [29%], respectively) reported adequate relief for all 3 months of treatment (difference 12% [4.7-19.2]). Alosetron also significantly decreased urgency and stool frequency, and increased stool firmness. Constipation occurred in 30% and 3% of patients in the alosetron and placebo groups, respectively.


CONCLUSIONS
Alosetron was well tolerated and clinically effective in alleviating pain and bowel-related symptoms in this population of women with IBS.
Camilleri
M
M
Gastrointestinal Research Unit, Mayo Clinic, Rochester, MN, USA.
Northcutt
A R
AR
Kong
S
S
Dukes
G E
GE
McSorley
D
D
Mangel
A W
AW
D000284:Administration, Oral; D000328:Adult; D002243:Carbolines / Q000009:adverse effects / Q000627:therapeutic use*; D003109:Colonic Diseases, Functional / Q000175:diagnosis / Q000188:drug therapy*; D004334:Drug Administration Schedule; D005260:Female; D005772:Gastrointestinal Transit / Q000187:drug effects; D006801:Humans; D008875:Middle Aged; D011985:Receptors, Serotonin / Q000187:drug effects; D044406:Receptors, Serotonin, 5-HT3; D012702:Serotonin Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D016896:Treatment Outcome
D002243:Carbolines; D011985:Receptors, Serotonin; D044406:Receptors, Serotonin, 5-HT3; D012702:Serotonin Antagonists; C090840:alosetron