The irritable bowel syndrome (IBS) drug market in the US, Europe and Japan will more than triple from $459m in 2008 to $1.52bn in 2018, according to a new report.

The Decision Resources report found that the market in the US, France, Germany, Italy, Spain, the UK and Japan can expect large-scale growth mostly on the back of several novel first-in-class therapy launches, expected from 2011 onwards.

The new drugs include including Salix‘s Xifaxan, Ironwood/Forest/Almirall/Astellas’s linaclotide, Tioga/ONO‘s asimadoline and Lexicon/Symphony Icon‘s LX-1031.

Two of these therapies in particular, linaclotide and asimadoline, have the potential to treat motility and pain symptoms associated with IBS, which will afford them a distinct advantage over available drugs, according to the report.

Decision Resources analyst Iva Holder said that linaclotide will enter the highly underserved market for constipation-predominant IBS and with launches anticipated in the US and Europe, it is forecast to be a major contributor to market growth.

“Although linaclotide will capture a relatively small percentage of the total patient share, it will account for 40% of overall market sales in 2018 due to its premium pricing,” Holder said.

The Pharmacor 2010 report also points to concerns about serious side effects associated with 5-HT-receptor-modulating therapies, which have created a much stricter and challenging regulatory environment for developers of treatments for IBS.

As a result, few new therapies have reached the market in recent years, creating further opportunity for the development of novel therapies for the indication.