Spain's Almirall  and partner Ironwood Pharmaceuticals have presented positive late-stage data on linaclotide in patients who have irritable bowel syndrome with constipation.

The companies announced positive top-line results from an 803-patient Phase III trial which show statistical significance and clinically relevant improvement for linaclotide-treated patients over placebo both for abdominal pain/abdominal discomfort responder and IBS degree of relief responder over three months. Significant improvement was also achieved for the main secondary endpoints (stool frequency and consistency, straining and bloating).

Almirall added that the safety results were consistent with those observed in previous trials, although overall rates of discontinuation due to adverse events were 8% for linaclotide and 3% for placebo. Also more patients suffered from diarrhoea on the Ironwood/Almirall drug, 19% versus 4% on placebo.

Still, Per Olof Andersson, executive director of R&D at the Barcelona-headquartered group, said "these results are very promising and we believe linaclotide will be a valuable treatment in an area with such high unmet need". He added that the firms are looking forward to the results of a second pivotal trial in the fourth quarter led by Ironwood, after which filing dates in Europe will be determined.

Almirall licensed the European rights to linaclotide in May last year, paying an upfront fee of $40 million and taking a stake in Ironwood for a further $15 million.