Hepatitis B virus core-related antigen (HBcrAg) (HBcrAg)

Hepatitis B virus core-related antigen (HBcrAg) is a composite viral marker comprising three proteins encoded by the precore/core region of the HBV genome: the hepatitis B core antigen (HBcAg), the hepatitis B e antigen (HBeAg), and a 22-kDa precore protein (p22cr) (Source: Journal of Hepatology, 2018). HBcrAg serves as a critical surrogate marker for the presence and transcriptional activity of intrahepatic covalently closed circular DNA (cccDNA), which remains the primary obstacle to achieving a functional cure for chronic hepatitis B (Source: NIH, PubMed PMID: 30615913). Because HBcrAg levels remain detectable even when HBsAg is low or undetectable, it provides a more accurate reflection of the viral reservoir during nucleos(t)ide analogue therapy (Source: Hepatology Communications, 2020). Therapeutic interventions targeting the core protein, such as capsid assembly modulators (CAMs), directly impact the production and assembly of these antigens by disrupting the viral lifecycle (Source: Clinical Infectious Diseases, 2021). Additionally, HBcrAg is utilized clinically to predict the risk of hepatocellular carcinoma development and the likelihood of viral relapse following the discontinuation of antiviral treatment (Source: World Journal of Gastroenterology, 2020).

Other names

HBcrAgHepatitis B core-related antigenPrecore/core gene productsHBcAgHBeAgp22cr

Capsid assembly modulation, viral RNA degradation via RNA interference, inhibition of cccDNA transcription, and inhibition of reverse transcription.