Types of human leukocyte antigen and decrease in HCV core antigen in serum for predicting efficacy of interferon-Alpha in patients with chronic hepatitis C: analysis by a prospective study

A prospective study was conducted to evaluate the influence of host factors, including human leukocyte antigen (HLA), and viral factors, including hepatitis C virus (HCV) core antigen, on the response to interferon (IFN)-Alpha.

Natural IFN-Alpha was given to 66 patients with chronic hepatitis C at a dose of 9 million units per day for 2 weeks, followed by 9 million units three times a week for 22 weeks.

Sustained virological response without detectable HCV RNA in serum 24 weeks after the end of IFN therapy was achieved in 21 patients, while it was not in 32 patients; the remaining 13 patients were not evaluated. HCV core antigen and HCV RNA started to decrease 1 and 4 weeks, respectively, after the commencement of IFN in responders ( P = 0.02 and P = 0.05, respectively). On univariate analysis, age of 50 years or less ( P < 0.001); lack of HLA DR6 ( P = 0.018) or DR52 ( P < 0.041); platelets more than 14 x 10(4)/mm(3) ( P = 0.031); HCV core antigen 500 fmol/l or less ( P = 0.001); and HCV RNA 100 KIU/ml or less were predictive of response. On multivariate analysis, age 50 years or less (odds ratio [OR], 4.009; P = 0.039); lack of HLA DR6 (OR, 8.130; P = 0.027); IFN-naive (OR, 11.63; P = 0.016); HCV core antigen 500 fmol/l or less (OR, 10.61; P = 0.007); and genotypes other than 1b (OR, 8.929; P = 0.010) were predictive of response.

Lack of HLA DR6 determined the response to IFN. HCV core antigen was useful in predicting and monitoring the response to IFN.