van Campenhout MJH, Rijckborst V, Brouwer WP, et al. - Given a moderate correlation of serum hepatitis B core-related antigen (HBcrAg) level with covalently closed circular DNA (cccDNA), researchers investigated if the addition of HBcrAg in monitoring the effect of peginterferon (PEG-IFN) therapy for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) infection is valuable. There were 133 HBeAg-negative, mainly Caucasian CHB patients, treated with 48 weeks of PEG-IFN alfa-2a who were assessed for serum HBcrAg level. Observations suggest that among Caucasians with HBeAg-negative CHB, patients with treatment response show a stronger decline of HBcrAg during PEG-IFN treatment. Compared with hepatitis B virus DNA and quantitative hepatitis B surface antigen, HBcrAg was not superior in predicting response during PEG-IFN treatment.