Biotron's BIT-HBV001 Shows Superior Antiviral Activity Against Hepatitis B Compared to Standard Therapy
Key Insights
Biotron (search)'s lead candidate BIT-HBV001 (search) demonstrated potent antiviral effects in two mouse models, reducing HBV DNA (search) levels by 62-65% over 16 days of treatment.
The compound showed superior performance compared to tenofovir, achieving near-complete inhibition across five HBV (search) replication markers including 77% reduction in cccDNA (search), the persistent viral reservoir.
BIT-HBV001 (search) exhibited synergistic activity when combined with tenofovir against HBV DNA (search), suggesting potential for lower-dose combination therapies.
Biotron (search) (ASX:BIT) has reported significant advances in its Hepatitis B Virus (search) (HBV (search)) development program, with new data showing its lead candidate BIT-HBV001 (search) demonstrating superior antiviral activity compared to current standard-of-care therapy. The findings, conducted at the SCRIPPS Research Institute (search) in California, provide the most substantial evidence to date of the drug's capabilities across multiple laboratory and animal models.
Robust In Vivo Performance Across Mouse Models
The company evaluated BIT-HBV001 (search) in two widely used HBV (search) disease models: a genetically engineered mouse that expresses HBV in the liver, and a humanized model engrafted with human hepatocytes that can be infected with the virus and produce infectious particles. In both models, mice received regular dosing over 16 days, after which liver and blood samples were analyzed.
In the engineered Tg05-C57Bl/6 model, BIT-HBV001 (search) reduced HBV DNA (search) levels by approximately 65%, though levels of HBsAg remained unchanged. The humanized MUP-uPA-SCID/Beige model showed similar viral DNA reduction of about 62%, while also producing a significant reduction in HBsAg of about 48%. According to Biotron (search), this difference reflects the compound's unique mechanism of action across various stages of HBV (search) replication.
Superior Laboratory Performance Against Multiple Viral Markers
A follow-up in vitro study comparing BIT-HBV001 (search) to tenofovir (TDF), the current first-line therapy for chronic HBV (search), revealed striking differences in antiviral activity. BIT-HBV001 strongly inhibited all five HBV replication markers assessed, including 99.97% inhibition of HBV DNA (search), 97% inhibition of HBsAg, 97.6% inhibition of HBeAg (search), and 99.4% inhibition of pregenomic RNA (search).
Critically, the compound achieved a 77% reduction in cccDNA (search), the persistent viral reservoir that underpins chronic infection and represents a major barrier to achieving functional cure. In contrast, tenofovir significantly inhibited only HBV DNA (search), with minimal or no activity on the four remaining endpoints, consistent with its established clinical profile.
Synergistic Combination Potential
A combination study indicated that BIT-HBV001 (search) and tenofovir act synergistically to suppress HBV DNA (search), suggesting that lower doses of each drug could achieve the same antiviral effect. While no synergy was observed on other markers due to tenofovir's limited scope of action, the standard therapy did not interfere with BIT-HBV001's broader antiviral activity.
"This was an extensive series of experiments with our best HBV (search) drug against a complex challenging virus," said Biotron (search) Managing Director Michelle Miller. "We now have a clearer understanding of the mechanism of action of this new class of drug, which has demonstrated advantages over the current standard of care first-line treatment."
Intellectual Property and Clinical Significance
Biotron (search) has filed a patent covering BIT-HBV001 (search) and a series of related small-molecule compounds, including their structures, methods of manufacture and therapeutic use. The company positions these compounds as a new class of HBV (search) drugs capable of targeting pathways beyond those affected by current standard-of-care treatments.
Miller emphasized the clinical significance of the findings: "The inhibition of cccDNA (search), a marker of HBV (search) persistence, is particularly encouraging." Chronic HBV infection (search) affects an estimated 250 million people globally and is linked to serious complications including cirrhosis (search) and liver cancer (search).
The work builds on earlier studies that established the drug's safety profile in mice and identified appropriate dosage ranges for ongoing experiments, positioning BIT-HBV001 (search) as a promising next-generation therapy targeting viral persistence mechanisms not adequately addressed by existing treatments.