Mirum Pharmaceuticals has secured approval from the US Food and Drug Administration (FDA) for Livmarli (maralixibat) oral solution to treat cholestatic pruritus.

Livmarli is an oral, once-daily inhibitor of ileal bile acid transporter (IBAT). It is approved for treating two rare liver diseases that affect both children and adults.

The FDA has cleared the IBAT inhibitor for cholestatic pruritus in patients aged five years and older with progressive familial intrahepatic cholestasis (PFIC).

Mirum Pharmaceuticals has also filed an additional supplementary new drug application (sNDA) to provide a higher concentration formulation of Livmarli, which was used during the MARCH trial.

The sNDA is expected to allow label expansion for younger patients with PFIC, the biopharmaceutical company said.

Additionally, Livmarli is authorised in the US for patients aged three months and older, in Europe for two months and older, in Canada, and in other regions globally, for the treatment of cholestatic pruritus in individuals with Alagille syndrome (ALGS).

Mirum Pharmaceuticals CEO Chris Peetz said: “Livmarli has the potential to have a transformational impact for patients with cholestatic pruritus associated with PFIC, and importantly, offers an option for those patients with the rarest of subtypes.

“Thank you to the patients, families, and clinicians whose study participation made this approval possible.”

The approval was based on findings from the Phase 3 MARCH study, which is said to be the biggest randomised trial in PFIC.

It included 93 patients with a variety of hereditary PFIC types including PFIC1, PFIC2, PFIC3, PFIC4, PFIC6, and unknown mutational status.

Additionally, Mirum Pharmaceuticals has applied for approval of the IBAT inhibitor in PFIC for patients two months of age and older in Europe.

Livmarli has been granted orphan designation for ALGS and PFIC and breakthrough therapy designation for ALGS and PFIC type 2.

Mirum Pharmaceuticals’ late-stage pipeline consists of two investigational therapies for debilitating liver diseases.

Last year in September, the company completed the acquisition of Travere Therapeutics’ bile acid product portfolio including Cholbam and Chenodal for an upfront payment of $210m.