OBJECTIVETo investigate the clinical significance of neutralizing anti-interferon-alpha antibodies (NA) in chronic hepatitis B patients treated with recombinant interferon-alpha(rIFN-alpha).

METHODSOne hundred and eighty-one patients (128 male and 53 female) with histological proven chronic hepatitis B were treated with 5 MU recombinant interferon-alpha 1b (rIFN-alpha 1b) subcutaneously thrice weekly for 6 to 37 (median 10) months. For each patient, Specific detection of serum HBV DNA level with fluorescent-quantitative PCR, HBeAg with enzymoimmunoassay and NA with an antiviral neutralizing biological assay were performed during therapy.

RESULTSNA was found in 61 (33.7%) of 181 patients. At the end of treatment, complete-response was achieved in 17 (27.9%) of 61 patients with NA and in 54 (45.0%) of 120 patients without NA, respectively (chi2=4.979). For NA positive patients, the complete-response rate was significantly lower in those who had not achieved partial-response prior to or at the same time as NA occurred than in those who did (3.8%, 1/26, vs. 45.7%, 16/35, chi2 = 7.457). Moreover, it was lower in patients who either had 20pg/ml of serum HBV DNA or above or HBV DNA had being reduced by less than 60% recent 3 months, but higher in those who had less than 20pg/ml of HBV DNA and HBV DNA had being reduced by 60% or above (20.0%, 9/45, vs. 56.3%, 9/16, chi2 = 11.009).

CONCLUSIONNA may negate the antiviral effects of rIFN-alpha in chronic hepatitis B patients treated with rIFN-alpha, especially if they appear before partial-response or at the occasion at which serum HBV DNA level was not below 20pg/ml or HBV DNA had being reduced by less than 60% recent 3 months.