Clinical significance of changes in serum hepatitis B virus DNA titer in patients with chronic hepatitis B treated with interferon.
BACKGROUND: Interferon (IFN) has been used in the treatment of patients with chronic hepatitis B virus (HBV) infection. Nonetheless, the changes in serum HBV DNA titer during IFN treatment and the effect of these changes on the therapeutic results have not been well studied. METHODS: Twenty patients with chronic hepatitis B who were positive for serum hepatitis B e antigen (HBeAg) and HBV DNA received IFN-alpha 2a 4.5 million units by subcutaneous injection three times a week for 24 weeks. Twenty age- and sex-matched patients with chronic hepatitis B were selected as a control group. Treatment response was defined as the normalization of serum alanine aminotransferase (ALT) and the seroconversion of serum HBeAg 24 weeks after discontinuation of the IFN treatment. Serum HBV DNA was measured using the branched DNA (bDNA) signal amplification assay. RESULTS: There was no significant difference in pretreatment mean serum ALT and HBV DNA titer in either the IFN-treated or the control group. Treatment response was found in six (30%) of 20 IFN-treated patients and in four (20%) of 20 control patients (p > 0.05). Serum HBV DNA titer fell after IFN treatment and remained undetectable only in patients with final treatment response. Serum HBV DNA was negative at week 12 of the IFN treatment in four (67%) of six patients with treatment responses, significantly higher than in none (0%) of 14 patients without a treatment response (p = 0.001). Multivariate logistic regression revealed that the negativity of serum HBV DNA at week 12 of the IFN treatment successfully predicted treatment response. CONCLUSIONS: Thirty percent of the patients with chronic hepatitis B responded to IFN-alpha 2a 4.5 million units subcutaneously injected three times a week for 24 weeks. Negativity of serum HBV DNA measured by bDNA assay at week 12 of the IFN treatment may suggest a beneficial treatment outcome.