By Manas Mishra

(Reuters) – Gilead Sciences Inc said on Monday all combinations of its three drugs to treat NASH were unsuccessful in a mid-stage study, the latest failure in a string of trials seeking to develop the first approved treatment for the fatty liver disease.

NASH, or non-alcoholic steatohepatitis, is a fatty liver disease related to obesity that affects about 5% of the global population and is poised to become the leading cause of liver transplants.

Gilead’s study tested three experimental drugs selonsertib, cilofexor and firsocostat, that all work on different mechanisms.

The trial failed its main goal of recording a statistically significant increase in the proportion of patients that achieved improvement in fibrosis, or building up of scar tissue in the liver, without the worsening of NASH.

However, the company said some improvements were seen in multiple measures of fibrosis and liver function in patients with advanced fibrosis treated with a combination of firsocostat and cilofexor, compared with placebo.

Given Gilead’s past failures in NASH, expectations were low for the trial, Oppenheimer & Co analyst Hartaj Singh said prior to the data.

“People have started to realize that NASH is a very complicated disease,” said Singh.

“I’ve talked to a lot of people about Gilead over the last few months. Almost nobody asks me about Gilead’s NASH programs anymore,” Singh told Reuters.

With no approved treatments, rivals such as Cymabay Therapeutics and Intercept Pharmaceuticals Inc are racing to get a chunk of the market for NASH treatments, which by some estimates is expected to reach $20 billion by 2025.

Gilead said the three experimental drugs were generally well tolerated by patients as monotherapies and in dual combination regimens in the trial.

(Reporting by Manas Mishra and Tamara Mathias in Bengaluru; Editing by Vinay Dwivedi and Amy Caren Daniel)