GSK said on Monday it received the first global approval for its experimental hepatitis B drug Hibsago in Japan, marking a milestone as the country's first and only functional cure for the chronic condition.
The drug, known generically as bepirovirsen, received approval in Japan under the brand name Hibsago, offering an alternative to lifelong antiviral treatments. GSK projects the medication could generate peak annual sales exceeding £2 billion ($2.73 billion), supporting its goal of surpassing £40 billion in annual revenue by 2031.
Hibsago works through three mechanisms: blocking viral DNA replication, reducing hepatitis B surface antigen levels in the blood, and stimulating the immune response for sustained disease control. Late-stage clinical studies showed that nearly one in five patients achieved a functional cure for chronic hepatitis B, according to the company.
Separately, GSK's cancer therapy dostarlimabe, marketed as Jemperli, secured a priority review designation from the U.S. FDA for a potential new indication in locally advanced rectal cancer. The agency set February 2027 as the target decision date for the review, though an earlier ruling remains possible. The application builds on existing approvals for certain subtypes of endometrial cancer and follows prior FDA designations, including Breakthrough Therapy and Fast Track status.
GSK's shares were trading 0.5% lower at £1,909.00 in London on Monday morning.
