Japan’s Ministry of Health, Labour and Welfare (MHLW) has approved GSK’s Hibsago (bepirovirsen), an antisense oligonucleotide (ASO), as a functional cure for chronic hepatitis B (CHB) virus infection in adult patients who have received at least six months of prior nucleos(t)ide analogue therapy and meet pre-defined viral markers.
The approval marks the first global approval for bepirovirsen, and makes Hibsago the first and only treatment approved in Japan as a functional cure for CHB.
Tony Wood, chief scientific officer, GSK, said, “After 6-months of treatment with Hibsago, patients could be freed from lifelong therapy and reduce their risk of long-term liver complications. This is a major advance for CHB management and our innovative hepatology portfolio, and we look forward to further regulatory decisions in other countries.”
According to GSK, the approval was supported by results from the Phase III B-Well trials, which demonstrated a 19 per cent functional cure rate among adults with HBsAg levels of ≤3,000 IU/mL, compared with around 1 per cent with the current standard of care after one year of treatment.
Functional cure occurs when the hepatitis B virus DNA and viral protein – HBsAg – are undetectable for at least 24 weeks after stopping all treatment. This indicates the disease is controlled by the immune system without medication. GSK said the loss of HBsAg is associated with up to an 89 per cent reduction in risk of liver cancer and a 62 per cent reduction in risk of all-cause mortality.
The approval was accelerated under Japan’s SENKU designation, which is granted to innovative medicines with the potential to address high unmet medical needs.
GSK licensed bepirovirsen from Ionis Pharmaceuticals and collaborated with the company on its development. The drug has also received Fast Track and Breakthrough Therapy designations from the US FDA, as well as Breakthrough Therapy and Priority Review designations in China.
GSK is continuing regulatory submissions for bepirovirsen in multiple countries, with a US decision expected in the coming months. The company is also evaluating the treatment in future sequential treatment strategies.
