Diseases & conditions

GSK Drug Shows Potential Cure for Chronic Hepatitis B

Is bepirovirsen a genuine breakthrough for hepatitis B or is it too early to celebrate a cure?

Published MAY 28

GSK Drug Shows Potential Cure for Chronic Hepatitis B

Story

Above: Hepatitis B virus. Image credit: Cavallini James/BSIP/Universal Images Group/Getty Images

The Facts

Phase 3 trial results for bepirovirsen, an investigational antisense oligonucleotide developed by GSK and Ionis Pharmaceuticals, published in the New England Journal of Medicine on Thursday, show that the drug functionally cured 1 in 5 patients with chronic hepatitis B infections, meaning they remained virus-free without treatment for at least six months.
BioSpace
NEJM
Pooled data from the B-Well 1 and B-Well 2 trials, conducted across 29 countries and involving more than 1,838 patients, showed a 19% functional cure rate in the overall study population, compared with 0% in the placebo group.
National Geographic
FierceBiotech.com
Among participants with baseline hepatitis B surface antigen at or below 1,000 IU/mL — representing roughly 45% of diagnosed chronic hepatitis B cases globally — a functional cure rate of 26% was recorded, versus 0% in the placebo group.
AJMC
FirstWord Pharma
In the pooled safety analysis, serious adverse events occurred in 7% of bepirovirsen recipients versus 4% of placebo patients. The most common adverse events were injection site erythema, local pain and temporary rises in alanine aminotransferase levels.
AJMC
NEJM
Bepirovirsen is under priority review by the U.S. Food and Drug Administration with Breakthrough and Fast Track Designation and is also under review in Europe, Japan and China. GSK anticipates the first regulatory decisions in the third quarter of 2026.
BioSpace
FirstWord Pharma
The current standard of care for chronic hepatitis B typically requires lifelong antiviral therapy, with functional cure achieved in less than 1% of patients. The disease affects more than 240 million people worldwide and causes approximately 1.1 million deaths annually.
Morning Star
The New York Times

Sources Split

LEFT

CENTER

RIGHT

ESTAB
CRIT

CENTER

PRO
ESTAB

The Spin

Narrative A

Bepirovirsen is a genuine breakthrough for the 240 million people living with chronic hepatitis B — a disease that kills 1.1 million annually and currently demands lifelong treatment. About 1 in 5 patients achieved a functional cure, meaning the immune system controls the virus without any medication. That's a massive leap from the less-than-1% functional cure rate of existing standard care.

GSK

Narrative B

Headlines describing a hepatitis B cure may overstate early results because the treatment achieved a functional cure in only a minority of trial participants. Researchers still lack long-term evidence proving patients remain permanently virus-free, while side effects, accessibility and high treatment costs remain concerns. Chronic hepatitis B remains challenging, and broader studies are necessary before celebrating a cure.

CNN