The TherVacB project (A Therapeutic Vaccine to Cure Hepatitis B), a European research initiative coordinated by Helmholtz Munich with IDIBAPS participation, has now reached a major milestone with the launch of its clinical trial in patients. Building on over a decade of research, the project aims to deliver a novel, affordable, and curative immunotherapeutic approach to chronic hepatitis B. This integrated approach spans basic research, preclinical and clinical development, and is supported by tools such as a European HBV Patient Registry and inclusive outreach strategies—informed by ethical guidance on the use of social media-based recruitment—to help reach individuals not yet engaged in regular medical care.
TherVacB’s milestone in patient recruitment follows a successful phase 1a trial in healthy volunteers, in which the TherVacB vaccine candidate demonstrated a favourable safety profile and triggered the desired immune responses. The TherVacB EU project consortium now advances to a multi-centre phase 1b/2a trial, evaluating the safety, tolerability, and immune efficacy of the vaccine in patients with chronic HBV infection who are receiving standard antiviral therapy.
“TherVacB is an immune therapy aiming to empower the immune system to control or even eliminate the virus. This approach, when combined with prophylactic vaccination, screening, and awareness, supports the global goal of eliminating hepatitis B as a public health threat”, said Ulrike Protzer, Project Coordinator of TherVacB and Director of the Institute of Virology at Helmholtz Munich and the Technical University of Munich.
Xavier Forns, head of the Viral, genetic and immune-mediated liver diseases IDIBAPS research group, and Sabela Lens, IDIBAPS researcher, add: “If successful, TherVacB could become the first therapeutic vaccine to offer a functional cure, an outcome current antiviral therapies do not achieve. This shall significantly reduce the burden of disease, prevent progression to cirrhosis and liver cancer, and lower hepatitis B-related mortality worldwide.
Trial Design and Patient Impact
The clinical trial, which began in June 2025, It is enrolling a total of 81 patients across multiple international clinical sites in Germany, Italy, Spain, the United Kingdom, and Tanzania. The study is designed in two sequential phases:
- Phase 1b: Patients receive ascending doses of the vaccine components to establish the safest and most effective regimen.
- Phase 2a: The optimal dose selected from Phase 1b will be tested in a larger group of patients to confirm safety and evaluate the antiviral effect in chronically infected patients.
About the TherVacB EU Project
TherVacB is a European research project supported by the EU Horizon 2020 programme under Grant Agreement No. 848223, with a total funding of 10 million euros. Coordinated by Helmholtz Munich, the project runs from January 2020 to December 2026 and brings together leading expertise in virology, immunology, and clinical vaccine development. It also includes ethical research on social media-based patient recruitment, addressing regulatory and societal considerations through a dedicated study.
The TherVacB consortium consists of 17 partners from four European countries (Germany, UK, Spain, Italy) and Tanzania, including academic institutions, university hospitals, public health research centres, SMEs, and consultancies. In addition to clinical and translational research, TherVacB supports patient identification through the European HBV Patient Registry. A clinical site in Tanzania strengthens local capacity for diagnosis and treatment. Multilingual outreach ensures broad access to project information.
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 848223. This press release reflects only the author’s views and the European Commission is not liable for any use that may be made of the information contained therein.
