Virion Therapeutics and Barinthus Bio have announced promising developments in their respective clinical trials for chronic hepatitis B (CHB) therapies. Virion's VRON-0200, a T cell-based immunotherapy, has completed enrollment in the first two cohorts of its Phase 1b trial, while Barinthus Bio shared encouraging results from its ongoing Phase 2b HBV003 trial evaluating VTP-300.
Virion Therapeutics' VRON-0200 Phase 1b Trial
Virion Therapeutics, a clinical-stage biotechnology company, announced the completion of enrollment in the first two cohorts of its Phase 1b clinical trial evaluating VRON-0200 for HBV functional cure. Twenty-seven patients with chronic HBV infection have been dosed with VRON-0200 as a single (Prime), or Prime and Boost, intramuscular injection. The trial aims to assess the safety, tolerability, immunology, and clinical measures of VRON-0200 in non-cirrhotic, HBeAg positive or negative, chronic hepatitis B patients currently taking nucleos(t)ide antiviral therapy with HBV DNA < 40 IU/mL and HBsAg < 500 IU/mL (< 1,000 IU/mL for Cohort 3).
Sue Currie, PhD, COO of Virion, stated that the rapid enrollment reflects the strong interest in effective, safe, and easily administered immunotherapies for chronic HBV. Previous data from the study indicated that a single VRON-0200 injection was safe and well-tolerated, inducing immune responses and anti-HBV activity despite impaired HBV immunity in most patients prior to treatment.
VRON-0200 is designed to amplify, broaden, and enhance T cell responses, potentially including T cells not normally activated during chronic HBV infection, leading to improved viral control. A third cohort is now underway, investigating VRON-0200 in combination with investigational anti-HBV agents, including elebsiran and tobevibart.
Barinthus Bio's VTP-300 Phase 2b Trial
Barinthus Biotherapeutics shared encouraging results from its ongoing Phase 2b HBV003 trial, which evaluates VTP-300, an immunotherapy combined with low-dose nivolumab for chronic hepatitis B (CHB). Out of 121 participants, 8 achieved HBsAg loss, with 2 meeting the functional cure criteria. Notably, two participants who discontinued nucleos(t)ide analogue (NUC) therapy seroconverted to HBsAb positivity, indicating potential long-term infection control.
The trial focuses on participants with HBsAg levels ≤200 IU/mL, showing the strongest responses. Among those assessed for NUC discontinuation, 66% maintained therapy-free status, and durable HBsAg declines were observed across treatment groups. Preliminary safety data confirmed that the combination therapy was well tolerated without significant adverse events.
According to Leon Hooftman, MD, the chief medical officer for Barinthus Biotherapeutics, VTP-300 stimulates the immune system and encourages the production of de novo, disease-specific T cells, enabling the immune system to control the virus in the long term and potentially reach a functional cure.
The Need for New HBV Therapies
Chronic hepatitis B remains a significant global health issue, with an estimated 296 million people infected worldwide and 820,000 deaths per year from HBV-related liver complications. Current standard of care requires lifelong antiviral therapy to maintain control of the virus, highlighting the urgent need for curative therapies.
