Gilead has new data backing up its liver disease candidate GS-9674 in non-alcoholic steatohepatitis (NASH), tipped as one of the next big growth markets for pharma.
The phase 2 data presented at The Liver Meeting show that farnesoid X receptor (FXR) agonist GS-9674 was able to reduce liver fat content and improve biomarkers of liver function compared to placebo in patients with NASH, which is characterised by a build-up of fat that can lead to fibrosis, cirrhosis, and in some patients, the need for a liver transplant.
In the NASH study, 39% of patients taking a high dose of the drug once daily for 24 weeks experienced at least a 30% reduction in liver fat, compared to 12.5% of the placebo group.
The new data shows Gilead’s drug is working as expected, but analysts said the results don’t look particularly robust when compared to Intercept Pharma’s Ocaliva (obeticholic acid), which is already on the market for primary biliary cirrhosis (PBC) and in phase 3 for NASH patients with cirrhosis.
Gilead has positioned GS-9674, a non-bile acid FXR, as having fewer side effects than Ocaliva, particularly pruritus (itching). Ihis was seen in 14% of the high-dose group compared to 4% of the placebo arm, but still compares favourably to Ocaliva which – according to the EMA – can cause itching in 60% of recipients or more.
All eyes are now on new data from a rival FXR agonist from Novartis, called tropifexor, which is due to be reported at The Liver Meeting later today and, according to some analysts, is less likely to cause itching.
Gilead has said it intends to continue development of GS-9674, however, and the latest results nevertheless put it another step further on the path to developing an effective NASH treatment, and address a market that some analysts have predicted could be worth upwards of $20bn.
The company has said that it believes combination therapy will be the key to having a big impact in NASH, and to the that end it is combining GS-9674 with two other candidates – ASK1 inhibitor selonsertib and ACC inhibitor GS-0976 – in a phase 2 trial that is due to read out next year.
It’s facing some strong competition there too, however, with Novartis and Pfizer recently agreeing to join forces to develop combination NASH drugs. Novartis is contributing tropifexor – currently in phase 2 – while Pfizer’s is putting ACC inhibitor (PF-05221304), DGAT2 inhibitor (PF-06865571) and KHK inhibitor (PF-06835919) into the alliance. All Pfizer’s drugs are in early- to mid-stage development.
Orphan disease
Meanwhile, Gilead also reported phase 2 results with GS-9674 in another liver condition, a rare disease called sclerosing cholangitis that causes the network of ducts that drain bile from the liver to become inflamed and scarred over time.
Once again, in that study the FXR agonist was associated with a significant improvement in liver biochemistry and markets of cholestasis (reduced bile flow) compared to placebo.