Albireo Pharma on Tuesday said the FDA cleared Bylvay (odevixibat) to treat moderate-to-severe itching in patients aged three months and older with progressive familial intrahepatic cholestasis (PFIC), making it the first drug approved for all subtypes of the rare liver disorder. The decision comes a day after the company obtained European marketing authorisation for the once-daily ileal bile acid transport inhibitor, which decreases reabsorption of bile acids from the small intestines.

"Treating children with PFIC can be difficult and frustrating given the current treatment options," said Richard Thompson, principal investigator of the Phase III PEDFIC 1 and PEDFIC 2 trials on which both approvals were based, adding "Bylvay gives us a non-surgical option and will change how we treat PFIC."

PEDFIC 1 included 62 patients, ages six months to 17 years, with PFIC type 1 or type 2 who were randomised to receive one of two oral doses of odevixibat or placebo once daily for 24 weeks. Bylvay achieved both its pruritus and serum bile acid primary endpoints against placebo, and was also and was well tolerated with very low incidence of diarrhoea/frequent bowel movements.

Albireo said PEDFIC 2, a single-arm, long-term extension study involving 79 patients with PFIC type 1, 2, and 3 between the ages of four months to 25 years, reaffirmed that Bylvay delivered sustained reductions in serum bile acids as well as improvements in pruritus assessments, growth and other markers of liver function in patients treated up to 48 weeks. Across both trials, Bylvay was well tolerated with diarrhoea/frequent stools being the most common treatment-related gastrointestinal adverse events, although the company said there were no serious side effects related to the drug.

Immediate US launch

Albireo says it will commercially launch Bylvay in the US in the coming days, adding that its focus now will be on access and reimbursement, sales promotion and patient support. With the approval, the FDA also issued a rare paediatric disease priority review voucher, which the company said it plans to monetise. The drugmaker indicated that it plans to directly commercialise Bylvay in the EU, including Germany, with a launch anticipated for September following German price listing.

Meanwhile, Bylvay is being studied in other rare paediatric cholestatic liver diseases, including the Phase III BOLD trial in patients with biliary atresia and the Phase III ASSERT study in Alagille syndrome. Top-line data from the ASSERT trial is expected in 2022 and the BOLD trial expected in 2024.