A Revolutionary Step Towards Combating Hepatitis B: nChroma Bio's CRISPR-Based Therapy
In a groundbreaking development, nChroma Bio has received the green light from Hong Kong's regulatory authorities to initiate a Phase 1/2 clinical trial for its lead candidate, CRMA-1001. This marks a significant milestone not only for the company but also for the entire field of hepatitis B research and treatment.
By: Gorm Palmgren - December 17, 2025
The decision to move forward with this advanced in vivo epigenetic editing program comes at a crucial juncture. The HBV field is shifting its focus from lifelong viral suppression to finite-course, functional cure strategies. And here's where it gets controversial: instead of relying on DNA cutting, nChroma Bio's approach utilizes CRISPR-derived transcriptional regulation, a less explored avenue in the treatment of chronic viral diseases.
"This regulatory clearance is a defining moment for nChroma and for the millions affected by chronic HBV," Jeff Walsh, CEO of nChroma Bio, emphasized. With the Certificate for Clinical Trial, nChroma can now test CRMA-1001 on human subjects with chronic hepatitis B virus infection, a condition that affects over 250 million people worldwide and often evades functional cure with current antiviral therapies.
Professor Man-Fung Yuen of The University of Hong Kong, the principal investigator for the trial, highlights the global impact of hepatitis B and the potential of CRMA-1001: "Hepatitis B poses a significant public health threat, leading to life-threatening conditions like cirrhosis and liver cancer. As a novel epigenetic silencer, I'm excited about the prospects of CRMA-1001 offering a functional cure for those living with HBV. I'm eager to contribute to a development that could transform the lives of millions."
CRMA-1001 represents a departure from traditional CRISPR gene-editing methods that rely on DNA cleavage. Instead, it employs a catalytically inactive Cas9 (dCas9) fused with proprietary epigenetic effector domains to silence viral gene expression without altering the DNA. This therapy targets both covalently closed circular DNA (cccDNA) and integrated HBV DNA (intDNA), the persistent viral reservoirs responsible for chronic HBV.
By inducing targeted DNA methylation at these viral loci, CRMA-1001 aims to shut down antigen production at the transcriptional level, potentially leading to a finite-course, functional cure. This distinction is crucial, as epigenetic silencing, by avoiding double-strand breaks, may reduce the risks associated with permanent genome modification. Additionally, it offers durability that RNA-based approaches often lack.
The regulatory clearance follows a series of promising preclinical data presented at The Liver Meeting 2025. CRMA-1001 demonstrated impressive results in both transgenic and AAV-HBV mouse models, achieving over three-log reductions in hepatitis B surface antigen (HBsAg) with durability extending to at least six months. Non-human primate studies further supported the platform's safety and durability, with a single dose producing sustained gene silencing for over a year.
"The findings underscore the potential of CRMA-1001's next-generation epigenetic silencing approach to achieve a durable functional cure for chronic HBV patients," nChroma Bio stated. The upcoming Phase 1/2 study will primarily focus on safety, tolerability, and early antiviral activity signals. While a functional cure is the ultimate goal, the mechanistic rationale has garnered interest from clinicians frustrated by the limitations of lifelong viral suppression.
"This regulatory clearance is a defining moment for nChroma and for the millions affected by chronic HBV," Jeff Walsh reiterated. "We believe we can reshape the trajectory of chronic hepatitis B with deeper, more sustained responses, leveraging the potency of our therapy to surpass the limits of existing and investigational treatments."
If successful, CRMA-1001 will not only validate nChroma's disease-first approach to genetic medicines but also establish CRISPR-based epigenetic regulation as a distinct therapeutic modality, separate from traditional gene editing and transient RNA therapies.
For the CRISPR medicine landscape, this program signifies a strategic shift from rewriting genomes to reprogramming gene expression. Durability, safety, and reversibility emerge as key design principles as the field progresses deeper into clinical trials.
The news was announced in a press release on December 16, 2025. To stay updated on the latest CRISPR medicine developments, sign up for the free weekly CMN Newsletter.
And this is the part most people miss: the potential impact of epigenetic regulation in the field of medicine is immense. It offers a new dimension to precision medicine, allowing for targeted interventions without permanent genetic modifications. But what are your thoughts? Do you think CRISPR-based epigenetic therapies will revolutionize the treatment of chronic viral diseases? Share your insights and let's spark a discussion!
