The US Food & Drug Administration (FDA) has given the green light to bepirovirsen (Hibsago) from GSK as a potential functional cure for adults with chronic hepatitis B – but with no cirrhosis – who are taking antiviral therapy, reports MedPage Today.
The approval was based on findings from the B-Well 1 and B-Well 2 trials, which demonstrated that nearly one in five patients taking the antisense oligonucleotide drug along with background antivirals achieved a functional cure, compared with none in a placebo group.
“This is the start of a new era in treating people with chronic hepatitis B,” said investigator Norah Terrault, MD, of Keck School of Medicine at the University of Southern California-Los Angeles, in a statement from GSK. “Bepirovirsen offers patients the potential to achieve functional cure after a short period of treatment, a long-standing goal for patients and physicians alike.”
In the phase 3 trials, 19%-20% of patients with hepatitis B surface antigen (HBsAg) levels of 3 000 IU/mL or less had a functional cure with bepirovirsen at week 72. In those with HBsAg levels of 1 000 IU/mL – about 45% of diagnosed cases worldwide – the functional cure rate reached 26%.
Chronic hepatitis B virus (HBV) infection can cause serious liver disease, including cirrhosis, and more than half of liver cancer cases globally can be attributed to hepatitis B.
Bepirovirsen is given as a six-month course and can be self-administered after the first dose.
The indication stipulates use along with nucleos(t)ide analogue reverse transcriptase inhibitor therapy in patients who have taken antiviral therapy for at least six months, have suppressed HBV blood levels, and have HBsAg levels of 3 000 IU/mL or less. The most common side effects are injection site reactions, fatigue, fever, and headache.
The FDA’s approved prescribing information includes a boxed warning about serious hepatic flares during treatment and low platelet counts, which can cause life-threatening thrombocytopenia.
Other warnings include risks of worsening kidney function, serious inflammatory adverse reactions such as vasculitis, and serious risks from improper injection. Because of those risks, patients using bepirovirsen require regular blood tests. Bepirovirsen is not recommended in patients with hepatitis D virus co-infection.
MedPage Today article – FDA Green Lights Potential Functional Cure for Chronic Hep B (Open access)
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The stealth and tragedy of hepatitis B in South Africa
Adults should screen at least once for hepatitis B – CDC recommendation
Majority of hepatitis B cases remain undiagnosed and untreated