Philadelphia PA, June 25, 2021 (GLOBE NEWSWIRE) -- Virion Therapeutics, LLC, developer of T cell-based immunotherapies that utilize the first genetically encoded checkpoint inhibitor, today presented an oral presentation entitled “VRON-0200, A therapeutic HBV vaccine with an intrinsic checkpoint inhibitor elicits broad CD8+ T cell responses and sustained antiviral declines in preclinical studies” at ILC.
Top line results following vaccination include:
- Induction of potent, broad, and sustained CD8+ T cells to key HBV antigens detectable in blood, liver, and spleen.
- 2-3 log10 copies/mL sustained HBV DNA declines in blood in all VRON-0200 vaccinated animals.
- The addition of gD, Virion’s proprietary genetically encoded inhibitor of an early T cell checkpoint, was required for substantial antiviral activity.
- Significant correlation between CD8+ T cell responses and antiviral declines (r-value: -0.491; p=0.004).
Chronic HBV infection impairs CD8+ T cell functions resulting in the loss of virus control. VRON-0200 is a therapeutic vaccine being developed for chronic HBV infections that uses key HBV antigens that are conserved between multiple viral genotypes and combined with a novel genetically encoded inhibitor of an early T cell checkpoint that blunts T cell activation. When inserted into a viral platform this combination enhances and broadens CD8+ T cell responses to the antigens expressed by the vaccine.
“The treatment of chronic HBV infection requires lifelong antiviral therapy to suppress the virus and prevent damage to the liver. The development of a treatment that can induce functional HBV-specific T cells to control the infection without the need for additional therapies has been highly sought after” said Andrew Luber, Pharm.D., President, and chief executive officer of Virion. “We believe VRON-0200 could be the key immune-modulator for use in combination ‘Functional Cure’ treatment strategies”.
“VRON-0200 is unique in its ability to stimulate broad and sustained HBV-specific CD8+ T cell responses. Due to the gD checkpoint inhibitor adjuvant, which allows for T cell stimulation to weaker antigens that are normally not triggered by a natural infection, we expect to achieve activation of new HBV-specific T cells rather than recall of already activated and potentially impaired T cells which failed when a patient was first exposed to the virus. That makes VRON-0200 so promising” said Hildegund Ertl, MD, Professor, Vaccine & Immunotherapy Center, at The Wistar Institute in Philadelphia PA and Co-Founder of Virion Therapeutics.
Jacob Lalezari, MD, Acting Chief Medical Officer of Virion and Director, Quest Clinical Research in San Francisco CA commented “The data presented today showing sustained multi-log viral declines following a single intramuscular injection is exciting and unlike any other immune-modulator, T cell therapy or therapeutic vaccine in development. If the unique mechanism of action of VRON-0200 is confirmed in humans, it would represent a significant advance in the treatment of Chronic HBV.”
Virion is scheduled to begin patient enrollment in a First-In-Human Phase 1b clinical trial at the end of 2022. The above presentation is available via the EASL-ILC meeting website, https://easl.eu/event/the-international-liver-congress-2021.
ABOUT VRON-0200
VRON-0200 is a pan genotypic, multi-region therapeutic vaccine for treatment of chronic HBV infections that contains three unique elements: 1) selected regions of HBV core and polymerase optimized for maximum immune recognition of multiple genotypes; 2) a series of heterologous chimpanzee adenoviral vectors to which humans have limited pre-existing neutralizing antibodies and that belong to different serotypes thereby allowing for optimal responses after prime-boost immunizations, and 3) gD, a genetically encoded inhibitor of an early T cell checkpoint that strengthens and broadens CD8+ T cell responses. In contrast to monoclonal antibody checkpoint inhibitor therapies, gD is locally acting and rapidly cleared which results in a low risk for “off target” side effects. In animals, a single intramuscular injection of VRON-0200 produces potent and broad CD8+ T cell responses with sustained multi-log reductions in HBV DNA in blood. A Phase 1b study in chronically HBV-infected patients is scheduled to begin enrollment in late 2022.
ABOUT VIRION THERAPEUTICS, LLC
Virion Therapeutics, LLC, is a science driven company developing innovative immune-based treatments for virally associated cancers and chronic viral infections utilizing the first genetically encoded checkpoint inhibitor given via vaccination. Our novel T cell-based immunotherapies induce potent, diverse, and sustained T cell-mediated immune responses, allowing us to target common diseases with unmet medical needs. Founded in early 2018 to advance technology licensed from The Wistar Institute, an international leader in biomedical research with special expertise in vaccine, cancer and infectious disease research, Virion has built an experienced biotechnology management team, augmented by its advisory board that has extensive domain knowledge in antiviral, vaccine, and oncology therapeutic arenas.