Affecting hundreds of millions of people, chronic hepatitis B is a widespread global health problem for which there is as yet no cure. In a preclinical study involving the German Center for Infection Research (DZIF), Heidelberg University Hospital, University Medical Center Hamburg-Eppendorf and the US company Vir Biotechnology, the potential of an engineered investigational human monoclonal antibody for the treatment of chronic hepatitis B and hepatitis D has been demonstrated. Based on the results, clinical trials with the monoclonal antibody VIR-3434 are ongoing.