London, UK | March 27, 2026
EMA Accepts First-in-Class Hepatitis B Therapy for Review
GSK has announced that the European Medicines Agency (EMA) has accepted the marketing authorisation application (MAA) for bepirovirsen, an investigational antisense oligonucleotide (ASO) therapy targeting chronic hepatitis B (CHB). This milestone positions bepirovirsen as a potential first-in-class treatment designed to address a major unmet medical need affecting approximately 3.2 million people in Europe and over 250 million globally.
Chronic hepatitis B remains a leading cause of liver cancer and liver-related mortality, with current standard-of-care therapies requiring lifelong treatment and delivering functional cure rates of only around 1%. The EMA review marks a significant step forward in advancing finite, curative treatment approaches that could transform disease management and reduce long-term healthcare burden.
Phase III Data Demonstrates Functional Cure Potential
The regulatory submission is supported by positive data from the Phase III B-Well 1 and B-Well 2 trials, which demonstrated statistically significant and clinically meaningful functional cure rates with bepirovirsen in combination with standard-of-care therapies. Functional cure—defined as sustained loss of hepatitis B surface antigen (HBsAg) and undetectable viral DNA for at least 24 weeks after treatment—represents the ultimate goal in hepatitis B therapy. The trials met all primary and key secondary endpoints, with particularly strong efficacy observed in patients with lower baseline HBsAg levels (≤1000 IU/ml).
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Importantly, the therapy showed an acceptable safety and tolerability profile, consistent with earlier studies. These findings highlight bepirovirsen’s potential to significantly improve cure rates compared to existing antiviral therapies, which primarily focus on viral suppression rather than eradication.
Innovative Mechanism Targets Viral Replication and Immunity
Bepirovirsen employs a triple-action mechanism, targeting the genetic material of the hepatitis B virus (HBV) to suppress replication, reduce viral protein levels, and enhance the body’s immune response. By degrading viral mRNA and pregenomic RNA, the therapy aims to restore immune control over the infection, potentially enabling long-term remission without continuous medication. The drug is also being explored as a backbone therapy for combination and sequential treatment strategies, which could further expand its clinical impact across broader patient populations.
Given that chronic hepatitis B contributes to approximately 56% of global liver cancer cases and causes over 1.1 million deaths annually, the development of therapies capable of delivering durable functional cure represents a major breakthrough in infectious disease and hepatology. With EMA review now underway, bepirovirsen could redefine the future treatment paradigm for hepatitis B, shifting from lifelong disease management to finite, curative interventions.
Source: GSK press release
