Biotron is preparing to advance its hepatitis B drug candidate into formal preclinical development after new laboratory studies found it showed strong antiviral activity against both hepatitis B and hepatitis D viruses, including in combination with an existing treatment for hepatitis delta.
The Sydney-based company said the studies, conducted at The Scripps Research Institute in San Diego, reinforced BIT-HBV001's potential as a treatment for chronic hepatitis B and for patients co-infected with hepatitis D, which causes the most severe form of viral hepatitis.
Biotron plans to undertake formal good laboratory practice preclinical studies and manufacture a GMP-grade drug product, with the aim of beginning first-in-human studies in the second half of 2027.
The company’s lead candidate has previously demonstrated activity against hepatitis B in cell-based assays, reducing a range of key viral markers including HBV DNA, hepatitis B surface antigen, hepatitis B e antigen, pregenomic RNA and cccDNA. The latter is considered an important marker of the persistent viral reservoir that contributes to chronic infection.
Biotron reported animal-model results in November last year and said in March that BIT-HBV001 was also active against hepatitis D virus. Hepatitis D is a satellite virus that can only infect people who already have hepatitis B, and co-infection is associated with a heightened risk of rapid progression to cirrhosis, liver failure and hepatocellular carcinoma.
In the latest work, researchers directly compared BIT-HBV001 with Myrcludex-B, marketed as Hepcludex, a treatment approved for chronic hepatitis delta infection in people co-infected with HBV and HDV.
Both treatments demonstrated substantial antiviral activity in infected cells. BIT-HBV001 reduced hepatitis B surface antigen by 98.1 per cent, compared with 93.8 per cent for Myrcludex-B. It reduced HBV DNA by 99.7 per cent, compared with 93.0 per cent for Myrcludex-B, while reductions in hepatitis D antigen were 81.0 per cent and 94.8 per cent respectively.
A second experiment tested the two drugs together. Biotron said analysis across four statistical models found significant antiviral synergy across three HBV and HDV replication endpoints, suggesting that combining BIT-HBV001 with Myrcludex-B could potentially achieve a similar degree of viral inhibition using lower doses of each treatment.
Managing director Michelle Miller said the results supported the program’s progression toward clinical testing and pointed to the candidate's broader potential in high-risk HBV and HDV co-infections.
“Over two billion people worldwide have been infected with HBV, and the World Health Organization estimates that more than 250 million people are chronically infected,” she said. “A functional cure for chronic HBV infection remains one of the most important unmet needs in antiviral medicine.”
