An experimental drug from GlaxoSmithKline has achieved what researchers call a “functional cure” for chronic hepatitis B in nearly one in five patients during clinical trials, according to new data reported by STAT News. The treatment, known as bepirovirsen, vastly outperformed current standard therapies in helping patients achieve sustained viral suppression.
Functional cure rates by treatment approach
Percentage of patients achieving sustained viral suppression, 24-week study period
Source: GSK Clinical Trial Data as reported by STAT News, 2026
Breakthrough results in phase 2 trials
The phase 2 clinical trial results showed that bepirovirsen helped 18% of patients achieve what researchers define as a functional cure, according to STAT News reporting on the study data. This means patients maintained undetectable levels of hepatitis B surface antigen (HBsAg) for at least 24 weeks after treatment ended, according to Centers for Disease Control and Prevention criteria.
In contrast, current standard treatments achieve functional cure rates of approximately 1% annually, according to the GSK trial data. The stark difference represents a potential paradigm shift in hepatitis B management, particularly for the estimated 296 million people living with chronic hepatitis B worldwide.
Bepirovirsen works through an antisense oligonucleotide mechanism, targeting viral RNA to prevent hepatitis B virus replication. This approach differs fundamentally from current nucleoside analogue therapies, which suppress but rarely eliminate the virus from patients’ systems.
Global burden drives urgent need for better treatments
Chronic hepatitis B remains a leading cause of liver cancer and cirrhosis globally, with the World Health Organization reporting approximately 820,000 deaths annually from hepatitis B-related complications. Current treatments require lifelong administration and rarely achieve complete viral clearance.
The disease disproportionately affects populations in sub-Saharan Africa and East Asia, where vertical transmission from mother to child remains common.
Safety profile and next steps
The GSK trial enrolled patients across multiple sites, with safety data showing manageable side effects primarily related to injection site reactions, according to the STAT News report. No serious adverse events were attributed directly to bepirovirsen treatment, though researchers continue monitoring long-term safety outcomes.
Phase 3 trials are expected to begin within the next 12 months, with GSK aiming to expand patient enrollment to include diverse populations and treatment-experienced individuals, according to the company’s plans reported by STAT News. Regulatory submissions could follow successful phase 3 completion, potentially making the treatment available within 3-5 years.
The 18% functional cure rate achieved with bepirovirsen represents an 18-fold improvement over current standard therapy, offering hope for millions of patients worldwide.
— GSK Clinical Trial Data as reported by STAT News, 2026
Key takeaways
- GSK’s bepirovirsen achieved functional cure in 18% of hepatitis B patients versus 1% with current therapy
- Treatment works through antisense mechanism targeting viral RNA rather than just suppressing replication
- Phase 3 trials expected to begin within 12 months, with potential approval in 3-5 years
Frequently asked questions
What is a functional cure for hepatitis B?
A functional cure means patients maintain undetectable levels of hepatitis B surface antigen for at least 24 weeks after treatment ends. While the virus may remain dormant in liver cells, it no longer replicates actively or causes progressive liver damage.
How does bepirovirsen differ from current treatments?
Unlike current nucleoside analogues that suppress viral replication, bepirovirsen uses antisense oligonucleotide technology to target and degrade viral RNA. This mechanism may allow for finite treatment courses rather than lifelong therapy.
When might this treatment become available?
GSK plans to initiate phase 3 trials within 12 months, followed by regulatory review processes. If successful, the treatment could potentially reach patients within 3-5 years through standard approval pathways.
The promising results position bepirovirsen as a potential game-changer for hepatitis B treatment, offering hope for achieving WHO’s goal of eliminating viral hepatitis as a public health threat by 2030.
Source: STAT+: Experimental hepatitis B treatment was a ‘functional cure’ for nearly 1 in 5, new data show
