Ironwood Pharmaceuticals has decided to discontinue the IW-3718 development programme after the Phase III IW-3718-302 trial missed its primary endpoint in refractory gastroesophageal reflux disease (GERD) patients.

The drug candidate failed to demonstrate a statistically significant improvement in heartburn severity.

IW-3718 is a gastric-retentive formulation of colesevelam. It is designed to maintain bile-acid sequestrant in the stomach for a longer duration, where it was positioned to stop bile prior to reaching the oesophagus.

An independent data monitoring committee reviewed data from IW-3718-302 and found that the study failed to meet the necessary criteria. The drug candidate was generally well-tolerated in trial participants.

Based on these results, the company intends to halt IW-3718 development. This includes termination of enrolment in IW-3718-301, another Phase III trial assessing the investigational drug.

The company is also planning an organisational restructuring and cutting down of the current workforce by almost 35%.

The company also intends to decrease the headcount by about 100, to have approximately 210 full-time employees by the first quarter of next year.

With workforce reduction, Ironwood estimates to save at least $45m annually and around $50m by discontinuing the IW-3718 programme. Cost savings achieved through this restructuring would total to more than $95m.

Ironwood anticipates one-time costs of approximately $10-$12m associated with discontinuing development of IW-3718, mainly due to planned workforce reduction.

Anticipating economic challenges related to Covid-19, Ironwood plans to restructure its commercial organisation.

It will focus on maximising the commercialisation of Linzess, a treatment for patients with irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC).

Ironwood CEO Mark Mallon said: “We have made the difficult decision to re-align our resources and capital with our business moving forward.

“With a streamlined organisation that we believe will be positioned well to deliver in this current environment, we aim to continue our efforts to maximise Linzess and to drive further growth and profitability.”

In May last year, Ironwood and Allergan reported results of Phase IIIb clinical trial of Linzess on multiple abdominal symptoms in adult patients with IBS-C.