Virion Therapeutics Reports Progress Towards HBV Functional Cure with Continued HBsAg Declines, Without Rebound, Up to Two Plus Years, After a Single VRON-0200 Dose, From its Phase 1b Study at EASL 2026

Highlights from the Data Presentation

• VRON-0200 was safe and well tolerated, with no serious treatment-related adverse events, treatment discontinuations, or treatment-related clinical laboratory abnormalities reported
• At end of study (one year after their prime VRON-0200 dose; Day 360), 85% (23/27) of patients had HBsAg declines that were sustained and/or continued to decline – 12/23 (52%) patients had a greater than 50% reduction (4 had a 1 log₁₀ IU/mL or greater decline)
• After end of study, HBsAg levels, up to 846 days after VRON-0200 prime dose, were available for 12 patients; 11/12 (92%) had continued HBsAg declines, no patient had HBsAg rebound, 2 (17%) achieved HBsAg loss, and 8 (75%) and 6 (50%) patients had >0.5 and >1.4 log₁₀ IU/mL declines, respectively, from Day 1
• A single VRON-0200 dose, with its ease of administration, favorable safety profile, and durable anti-HBV activity, may be sufficient alone for some chronically HBV-infected patients, for HBV Functional Cure
• The durability of VRON-0200’s anti-HBV activity may allow for flexibility (e.g., timing) for adding antivirals later, if needed, when using the “Spark and Fan” approach where an upfront VRON-0200 dose “primes” (e.g., “Spark”) an anti-HBV immune response, which is then boosted (e.g., “Fan”) by an antiviral regimen that removes the virus
• The results from this Phase 1b study were concurrently published in The Lancet Microbe and is now available for download

PHILADELPHIA--(BUSINESS WIRE)--Virion Therapeutics, LLC, a clinical-stage biotechnology company, developing novel T cell-based immunotherapies that utilize checkpoint modifiers, today announced at the EASL Congress 2026 (The European Association for the Study of the Liver) in Barcelona, Spain, that a single intramuscular dose of VRON-0200, its novel, first-in-class, immunotherapy for HBV Functional Cure, induced HBV-specific immune activation, restoration, and continued HBsAg declines, without rebound, up to 2+ years post dosing, in the majority of chronically HBV-infected treated patients with long term follow up. These data, presented as an oral presentation by Professor Edward Gane, M.D., from the University of Auckland, also highlighted VRON-0200’s ongoing favorable safety and tolerability profile, and sustained HBsAg declines, up to 3 months post the last dose of investigational antivirals, when given in combination with a single VRON-0200 prime dose.

Professor Gane, M.D. commented: “The goal of therapy in chronically HBV-infected patients is to have a finite course of treatment that, upon discontinuation, maintains viral suppression without the need to re-initiate antiviral agents (referred to as Functional Cure). While significant advances in the treatment of Chronic HBV are being made, HBV immune restoration, needed for viral control, appears to be limited, resulting in high rates of rapid off treatment viral rebound. What makes these VRON-0200 data so remarkable are the continued HBsAg declines, without rebound, for up to 2+ years highlighting the critical role of a patient’s own anti-HBV immune responses in controlling the virus. These long-term follow-up data suggest that VRON-0200’s anti-HBV activity may be sufficient for some patients alone, or when combined with other investigational treatments, to prevent viral rebound after Functional Cure treatment. VRON-0200’s ability to restore a patient’s own anti-HBV responses is a significant advance for the field and opens up a wide range of possible future Functional Cure treatment options.”

“It is now accepted that immune modulation is a critical part of a functional cure for patients with chronic HBV. However, restoring a patient’s own immune responses against the virus, let alone one that is durable off antiviral treatment, has been difficult,” said Dr. Sue Currie, COO, Virion, and one of the study authors. Currie added, “These new VRON-0200 longer term data show that not only does VRON-0200 stimulate (“Spark”) sustained anti-HBV activity in the majority of patients, without rebound, but this activity actually improves over time, which, for some patients, may be enough to clear the virus on their own. Given these positive clinical data, a Phase 2B SPARK-B study is in development which will evaluate off treatment (nucleos(t)ide discontinuation) Functional Cure and include patients with higher baseline HBsAg levels (<3000 IU/mL). Additionally, VRON-0200 is being considered for other chronic HBV populations including HIV/HBV and HDV/HBV co-infection, and MASH. VRON-0200’s durability and potency, ease of administration (a single intramuscular injection), and favorable safety profile, position it to be the foundational backbone agent for use alone, or in new combination therapies, that could produce meaningful Functional Cure rates for the almost 260 million persons living with chronic HBV worldwide.”

Professor Grace Wong, M.D., from the Chinese University of Hong Kong, and one of the study investigators, noted: “New Chronic HBV treatments have shown improved Functional Cure rates, and several are rapidly advancing towards regulatory approval. While beneficial, clinical responses appear to be restricted to select patient populations (e.g., low baseline HBsAg levels), and factors such as inconvenient dosing, safety and tolerability profiles, and cost, may limit their widespread use. What makes VRON-0200 so exciting is that with a single, convenient, and well tolerated dose, the potential exists for improving overall response rates by preventing viral rebound upon treatment discontinuation. I look forward to continuing to follow VRON-0200’s progress as it advances into later stage clinical trials.”

The presentation is available for download at www.VirionTx.com and more details of this study can be found at ClinicalTrials.gov (Identifier: NCT06070051).

About Chronic Hepatitis B
Despite a preventative vaccine, cases of chronic hepatitis B (CHB) continue to rise, with an estimated 254 million persons infected worldwide and 1.1 million deaths per year from HBV-related liver complications. Chronic HBV remains a global health issue with a high unmet medical need since there is no cure available. The current standard of care requires lifelong antiviral therapy to maintain control of the virus. Current and investigational HBV Functional Cure treatments have been limited by their inability to restore a patient’s own immune responses against the virus. As a result, once treatment is discontinued, and the antiviral agents are no longer present, viral rebound typically occurs. As a result, immune modulators are now considered necessary for future cure treatment strategies.

About VRON-0200
VRON-0200 is an investigational therapeutic immunotherapy designed with the goal of providing a functional cure for chronic HBV infection. Clinical data from an ongoing Phase 1b trial have shown VRON-0200 to be safe and well tolerated, and, when given as a single intramuscular dose, was immunogenic, and able to “Spark” anti-HBV activity in chronically HBV-infected patients on nucleos(t)ide therapy alone, and, also, when given with combination antiviral therapies. These results suggest the potential of VRON-0200 to be a key backbone immune modulator for HBV functional cure treatments.

About Virion Therapeutics (Virion)
Virion Therapeutics, LLC is a clinical-stage company developing novel immunotherapies that utilize proprietary checkpoint modifiers to enhance/restore, broaden, and elicit sustained immune responses, with the goal to cure cancer and chronic infectious diseases. Virion’s pipeline now includes its lead VRON-0200 clinical program, and several additional IND-enabling programs, such as its VRON-0300 oncology program for advanced solid tumors, leveraging its proprietary platform technologies.

To learn more, visit www.VirionTx.com