A British pharmaceutical company announced Thursday that its experimental treatment for chronic hepatitis B demonstrated promising results in advanced clinical trials, with nearly 20% of participants achieving what researchers call a functional cure.
GSK shared comprehensive results from two clinical studies of bepirovirsen during a medical conference presentation on Thursday.
The treatment represents a cornerstone of GSK’s strategy to reach annual revenues exceeding £40 billion ($54 billion) by 2031. Company officials project the medication could generate peak yearly sales surpassing £2 billion.
According to GSK’s findings, a six-month treatment regimen with bepirovirsen enabled 19% of participants who began with surface antigen concentrations of 3,000 international units per millilitre (IU/ml) or lower to reach a functional cure. This classification requires patients to remain treatment-free for a minimum of six months while maintaining hepatitis B virus DNA and surface antigen levels below detectable thresholds.
Success rates increased to 26% among participants whose initial surface antigen levels measured 1,000 IU/ml or below.
Industry experts had previously suggested that response rates between 15% and 20% would represent meaningful progress and could lead to widespread clinical adoption.
Worldwide, more than 250 million individuals suffer from chronic hepatitis B, while existing standard treatments enable only 1% to 4% of patients to eliminate the virus for extended periods.
Current widely-prescribed nucleotide analogues typically require lifetime administration and control viral activity without completely removing it from patients’ systems.
“To have six months of injections to achieve functional cure of this magnitude … is, to me, a great advance in the management of my patients,” said Dr. Seng Gee Lim, lead investigator of the studies.
Dr. Lim noted that participants generally responded well to the medication, with most adverse reactions consisting of minor irritation at injection sites.
GSK has submitted applications for regulatory clearance of bepirovirsen to authorities in the U.S., Japan, China and Europe. The U.S. regulator is scheduled to announce its decision by October 26.
