The US Food and Drug Administration (FDA) has announced that it has approved Rezdiffra (resmetirom) for the treatment of adult patients with noncirrhotic non-alcoholic steatohepatitis (NASH) with moderate-to-advanced liver scarring (fibrosis), for use alongside diet and exercise.

This approval follows an analysis of the safety and efficacy of the drug based on a surrogate endpoint at month 12 in a 54-month, randomised, double-blind, placebo-controlled trial, which measured the extend of liver inflammation and scarring.

At the 12-month mark, liver biopsies demonstrated that a larger proportion of those treated with Rezdiffra achieved NASH resolution or an improvement in liver scarring, compared to those treated with a placebo. Approximately 26-27% of patients on 80mg of the drug and 24-36% of those on 100mg experienced NASH resolution and no worsening of liver scarring compared to only 9-13% of those in the placebo group.

According to the FDA’s press release, it ‘approved Rezdiffra under the accelerated approval pathway, which allows for earlier approval of drugs that treat serious conditions and address an unmet medical need, based on a surrogate or intermediate clinical endpoint that is reasonably likely to predict clinical benefit. The required aforementioned 54-month study, which is ongoing, will assess clinical benefit after 54 months of Rezdiffra treatment’.

Nikolay Nikolov MD, active director of the Office of Immunology and Inflammation at the FDA’s Center for Drug Evaluation and Research, commented: “Previously, patients with NASH who also have notable liver scarring did not have a medication that could directly address their liver damage. Today’s approval of Rezdiffra will, for the first time, provide a treatment option for these patients, in addition to diet and exercise.”