Factors Predictive of Response to Interferon Therapy in Chronic HCV Infection

Kim, Yun Soo; Kwan, So Young; Suh, Dong Jin; Lee, Chang Hong

Abstract

BACKGROUND/AIMS: Although interferon-a(IFNa) is currently the most effective antiviral agent for treating patients with chronic hepatitis C, its efficacy is not always reliable. Factors suggested to infruence outcome of IFN-a therapy for chronic hepatitis C are histological activity, level of viremia and HCV genotype, etc. The aim of this study was to determine the relationship between several pretreatment factors and response to IFN-a therapy in patients with chronic HCV infection.
METHODS
Fifty-four patients with chronic HCV infection(47 with chronic hepatitis and 7 with liver cirrhosis) who received IFN-a(2a or 2b) therapy(3 6 MU, three times a week, for 3 12 months) were included. Level of serum HCV RNA(50 patients), HCV genotype(27 patients) and IgM anti- HCV(21 patients) during pretreatment period were assayed.
RESULTS
Overall, 19(35%) subjects achieved sustained response(SR), 12(22%) had transient response(TR) and 23(43%) did not respond (nonresponse;NR). Mean age of patients with SR, TR and NR was 46+ 10, 51+ 7.5 and 54+ 9.7 years, respectively(p<0.05 between SR and NR). Among 30 patients with biopsy-proven chronic hepatitis, 13(43%) achieved SR;but only one(14%) in 7 patients with liver cirrhosis. Mean serum HCV RNA level(X10' copies/ml) was higher in nonresponders(7,7+ 13.0) compared with SR(2.3+ 2. 7) or TR(3.1+ 4.9), although statistically insignificant HCV genotyping in 27 patients revealed type la in 5(18.5%), 1b in 14(52%), 2a in 5(18.5%), 2b in 1(3.7%) and 4 in 2(7%), respectively. In non-1b patients, SR rate was significantly higher than 1b patients(69.2% vs. 21.4%, p=0.03). Although IgM anti-HCV was positive in 12(57%) among 21 patients studied, the positive rate and the titer of IgM anti-HCV was not significantly different in three groups.
CONCLUSION
Our results suggest that in patients with chronic hepatitis C, infection with genotype 1b, old age, high serum HCV RNA level and the presence of cirrhosis would predict poor response to IFN therapy.