Safety and Antiviral Activity of a Monoclonal Hepatitis B Antibody: a Phase 1b, Open-label Trial in Individuals With Chronic Hepatitis D Infection

Hepatitis D virus (HDV) is a major global health issue, with an estimated 12 million people living with the infection worldwide. HDV infection requires the presence of hepatitis B virus (HBV), as it relies on hepatitis B virus for replication within the liver cells. Treatment options for HDV are limited and cannot cure the infection. The combination of concurrent HBV and HDV increases the risk of developing severe liver disease, including cirrhosis and liver cancer. This risk would significantly decrease if HDV is eliminated or reduced. Consequently, there is a need for the development of new treatment options. Colleagues at Rockefeller University in New York have identified the antibody HepB mAb19, which effectively reduces the amount of circulating HBV antigens. Since HDV depends on HBV to replicate, we will test this antibody as a potential treatment for HDV. The trial design is a phase 1b open-label aiming at including 15 study participants with chronic hepatitis D infection. All study participants will receive two or three dosis of the antibody, HepB mAB19, and will be followed for 60 weeks after the first HepB mAb19 infusion. This study will evaluate the safety and pharmacokinetics of this antibody, as well as its potential effects on viral levels of HDV RNA and antiviral immune responses in individuals living with chronic HDV infection.