GSK plc (LSE/NYSE:
GSK) today announced that the China National Medical Products
Administration (NMPA) has accepted for review a new drug
application (NDA) for bepirovirsen, an investigational antisense
oligonucleotide (ASO), for the treatment of adults with chronic
hepatitis B (CHB).
Chronic hepatitis B is a major public health challenge, affecting
more than 250 million people worldwide and an estimated 75 million
people in China1.
The current standard of care - typically nucleos(t)ide analogues -
often requires lifelong therapy and the functional cure rates
remain low, typically only 1%.[3] Functional
cure occurs when the hepatitis B virus DNA and viral protein -
hepatitis B surface antigen (HBsAg) - are undetectable in the blood
for at least 24 weeks after stopping all treatment, indicative of
the disease being controlled by the immune system without
medication. Functional cure is associated with significant
reduction in the risk of long-term liver complications, including
liver cancer.[4] Each
year, in China, approximately 450,000 deaths are caused by
CHB1.
The regulatory submission is supported by positive results from the
B-Well 1 and B-Well 2 Phase III trials, where bepirovirsen
demonstrated a statistically significant and clinically meaningful
functional cure rate. Functional cure rates were significantly
higher with bepirovirsen plus standard of care compared with
standard of care alone across all ranked endpoints, including in
patients with lower baseline HBsAg levels where an even greater
effect was observed. Bepirovirsen demonstrated an acceptable safety
and tolerability profile consistent with previous studies. These
data will be presented at a congress and submitted for scientific
peer-reviewed publication in 2026.
Bepirovirsen was granted Breakthrough Therapy designation in China
in August 2021, which is intended to expedite the review of
investigational drugs with potential for substantial improvement
over available therapies.
Clinical trial programme
B-Well 1 [NCT05630807] and B-Well 2 [NCT 05630820] trials are
global multi-centre, randomised, double-blind, placebo-controlled
trials conducted in 29 countries. They assessed the efficacy,
safety, pharmacokinetic profile, and the durability of functional
cure in nucleos(t)ide analogue (NA)-treated in non-cirrhotic
participants with CHB and baseline surface antigen (HBsAg)
≤3000 IU/ml. The primary endpoint assessed the proportion of
participants achieving functional cure in patients with baseline
surface antigen (HBsAg) ≤3000 IU/ml. A key ranked secondary
endpoint evaluated functional cure in patients with baseline HBsAg
≤1000 IU/ml.
About chronic hepatitis B
Hepatitis B is a viral infection that can cause both acute and
chronic liver disease. Chronic hepatitis B occurs when the immune
system is unable to clear the virus, resulting in long-lasting
infection. CHB affects more than 250 million people worldwide. Each
year, the disease causes approximately 1.1 million deaths, and
approximately 450,000 deaths in China.1 Many
patients often require lifelong antiviral therapy for viral
suppression; making functional cure a critical goal in disease
management.
About bepirovirsen
Bepirovirsen is a triple action investigational antisense
oligonucleotide (ASO), designed to recognise and orchestrate the
destruction of the genetic components (i.e. mRNA and pregenomic
RNA) of the hepatitis B virus that can lead to chronic disease,
potentially allowing a person's immune system to regain control.
Bepirovirsen inhibits the replication of the viral genome in the
body, suppresses the level of hepatitis B surface antigen (HBsAg)
in the blood, and stimulates the immune system to increase the
chances of a durable and sustained response.
Bepirovirsen is also being evaluated as a potential backbone
therapy for future sequential treatment strategies aimed at
expanding functional cure to broader patient
populations.
GSK licensed bepirovirsen from Ionis Pharmaceuticals and
collaborated with them on its development. Bepirovirsen has been
recognised by global regulatory authorities for its innovation and
potential to address significant unmet need in hepatitis B, with
Fast Track designation from the US FDA, Breakthrough Therapy
designation in China and SENKU designation in Japan. Bepirovirsen
is currently not approved anywhere in the world.
About GSK
GSK is a global biopharma company with a purpose to unite science,
technology, and talent to get ahead of disease together. Find out
more at www.gsk.com.
GSK cautions investors that any forward-looking statements or
projections made by GSK, including those made in this announcement,
are subject to risks and uncertainties that may cause actual
results to differ materially from those projected. Such factors
include, but are not limited to, those described in the "Risk
Factors" section in GSK's Annual Report on Form 20-F for
2025.
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WC1A
1DG
[1] WHO
Global Hepatitis Report 2024. Available at https://www.who.int/publications/i/item/9789240091672 (last
accessed March 2026)
[2] Rumgay
H et al . Global burden of primary liver cancer in 2020 and
predictions to 2040. J Hepatol. 2022;77:1598-1606. doi:
10.1016/j.jhep.2022.08.021
[3] Slaets,
L. et al. "Systematic review with meta-analysis: hepatitis B
surface antigen decline and seroclearance in chronic hepatitis B
patients on nucleos(t)ide analogues or pegylated interferon
therapy" in GastroHep 2, 106-116 (2020)
[4] EASL,
"Clinical Practice Guidelines on the management of hepatitis B
virus infection" in Journal of Hepatology Volume 83, Issue 2,
August 2025, Pages 502-583. Available at:
https://www.sciencedirect.com/science/article/pii/S0168827825001746
(last accessed: January 2026)
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