Singapore: Astellas Pharma has obtained the marketing approval of Irribow OD 1 Tablets 2.5µg / 5µg (generic name: ramosetron hydrochloride) in Japan. They were approved for an additional formulation of Irribow Tablets with the indication of diarrhea-predominant irritable bowel syndrome (IBS-D ) in male.

Irribow OD Tablet is a drug for treating IBS-D developed using WOWTAB which is one of the Astellas' proprietary drug delivery technologies. It can be ingested without water since it quickly disintegrates upon contact with saliva in the mouth. It can be easily taken even by elderly patients and patients with impaired swallowing function. It is also useful for patients with avoided water consumption and meets various needs of patients. Astellas offers Gaster D Tablet for the treatment for peptic ulcers and gastritis, Harnal D Tablet for the treatment for functional symptoms of benign prostatic hyperplasia and Vesicare OD Tablet for overactive bladder, which were developed with using WOWTAB technology.

Irribow Tablet is a serotonin 5-HT3 receptor antagonist discovered by Astellas. Serotonin is a member of neurotransmitter which is greatly related to gastrointestinal motility, secretion and sensation. Stress may stimulate the serotonin release and activate the 5-HT3 receptors on enteric nerve, which induces the acceleration of intestinal transit resulting in diarrhea. In addition, the increase in intracolonic pressure also induces serotonin release, and it will bind to 5-HT3 receptor at the terminal of afferent neuron, causing intestinal nociceptive transmission to central nervous system.

Irribow Tablet improves abnormal defecation associated with the acceleration of intestinal transit by inhibiting 5-HT3 receptor selectively. It also improves visceral hypersensitivity by suppressing the transmission of intestinal nociception.

Astellas expects to further contribute to irritable bowel syndrome treatment by introducing into Japanese market Irribow OD Tablet which can further improve the compliance with its more convenient dosing option.