Epigenetic Therapy Silences Hepatitis B Virus in Early Trials
A new epigenetic therapy, CRMA-1001, has shown promise in silencing the hepatitis B virus (HBV) by adding chemical tags to viral DNA rather than cutting it. Developed by nChroma Bio and Italian researchers, the treatment targets both free-floating and integrated HBV DNA in the liver. Preclinical tests in human cells, mice, and monkeys yielded strong results with minimal side effects. A clinical trial has now begun in Hong Kong and New Zealand, with the first patient treated in January 2026. This approach aims to offer a potential cure for the 250 million people globally affected by chronic HBV, avoiding the cancer risks associated with traditional gene-editing methods.
Key points
- The therapy uses a modified Cas9 enzyme that lacks cutting activity to add methyl groups to HBV DNA, shutting down viral gene expression.
- It targets two forms of the virus: free-floating mini-chromosomes in liver cells and viral DNA integrated into the host genome.
- Preclinical studies in mice and monkeys showed efficacy with only temporary and minimal side effects.
- A clinical trial is underway in Hong Kong and New Zealand, testing multiple doses via intravenous infusion.
- The approach avoids the cancer risks associated with traditional DNA-cutting gene therapies for HBV.
Background
This development follows a broader trend in 2026 toward epigenome editing, where researchers focus on altering chemical marks that control gene activity rather than changing the underlying DNA sequence. Earlier this month, coverage highlighted the potential of this technology to treat diseases by rewriting gene expression without permanent genetic changes. Additionally, recent discoveries of ancient viral defense systems like VIPR have underscored the evolutionary history of gene-editing mechanisms, providing context for the development of safer, non-cutting therapeutic tools.
Why it matters
Chronic hepatitis B affects over 250 million people worldwide and often leads to liver cancer or severe disease rebound when medications are stopped. Current treatments rarely eradicate the virus. This epigenetic approach offers a potential one-time cure by silencing the virus's ability to replicate, addressing a major global health challenge without the safety concerns of traditional gene editing.
What to watch
The clinical trial in Hong Kong and New Zealand will test the safety and efficacy of multiple doses of CRMA-1001 in humans. Results from this trial will determine if the therapy can move to larger-scale studies and eventual approval as a standard treatment for chronic HBV.
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