GSK wins regulatory approvals for hepatitis B drug and cancer therapy

• Bepirovirsen approved in Japan as the first functional cure for chronic hepatitis B, offering a finite treatment course alternative to lifelong antiviral pills, with peak sales projected to exceed £2 billion ($2.73 billion) annually
• The drug works through three mechanisms: blocking viral DNA replication, lowering hepatitis B surface antigen levels, and boosting immune response for longer-lasting disease control
• Dostarlimab received FDA priority review for rectal cancer with a February 2027 action date, building on existing approvals for endometrial cancer subtypes and receiving both Breakthrough Therapy and Fast Track designations

GSK Wins Regulatory Approvals for Hepatitis B Drug and Cancer Therapy

Key Developments:

British pharmaceutical giant GSK announced two significant regulatory milestones on August 24. The company received Japan's approval for its chronic hepatitis B drug bepirovirsen (branded as Hibsago) and secured a priority FDA review for its cancer therapy dostarlimab (Jemperli) as a rectal cancer treatment.

Hepatitis B Drug - Bepirovirsen (Hibsago):

• First global approval granted in Japan, positioned as the country's first and only functional cure for chronic hepatitis B
• Works through three mechanisms: blocking viral DNA replication, lowering hepatitis B surface antigen levels, and boosting immune response
• Approval based on late-stage clinical studies demonstrating functional cure potential
• Offers finite treatment course alternative to lifelong antiviral medications
• GSK projects peak annual sales exceeding £2 billion ($2.73 billion)
• Key contributor to GSK's revenue target of over £40 billion by 2031

Cancer Therapy - Dostarlimab (Jemperli):

• FDA granted priority review for locally advanced rectal cancer treatment
• Currently approved for specific endometrial cancer subtypes
• Assigned FDA action date of February 2027, though decision could come earlier
• Previously received FDA Breakthrough Therapy and Fast Track designations
• Not yet approved for rectal cancer anywhere globally

Market Implications:

These approvals strengthen GSK's oncology and infectious disease portfolios, with bepirovirsen representing a potentially transformative treatment addressing significant unmet medical needs in hepatitis B management. The projected multi-billion revenue contribution supports GSK's ambitious 2031 growth targets.