Hepatitis B and D: an overview of the diagnosis and management

Chronic hepatitis B (CHB) represents a major global healthcare challenge with increasing morbidity and mortality because of the progression to cirrhosis and hepatocellular carcinoma (HCC). Hepatitis delta virus (HDV) is a defective virus that can propagate only in the presence of hepatitis B virus (HBV); it is the most aggressive form of viral hepatitis CHB is a dynamic disease that can be broadly categorized into four phases. HDV infection can develop after synchronous infection with HBV (co-infection) or alternatively after exposure to HDV from a patient with pre-existing CHB (superinfection). The primary treatment goal in CHB is to improve survival and quality of life by preventing disease progression and HCC development. Current treatment regimens are non-curative and, once initiated, treatment is long term in most cases. Functional cure, i.e. sustained HBsAg loss, is another goal, and novel agents in Phase II and III trial settings will contribute to achieving this target. Individuals with active HDV infection should also be offered antiviral treatment. Until recently, there were very limited options available, with conventional HBV treatments being either ineffective or poorly tolerated. More recently, the conditional approval of bulevirtide, a first-in-class HBV entry inhibitor, seems to have revolutionized the HDV treatment landscape.