LOSS OF SERUM HCV RNA AT WEEK-4 OF INTERFERON-ALPHA THERAPY IS ASSOCIATED WITH MORE FAVORABLE LONG-TERM RESPONSE IN PATIENTS WITH CHRONIC HEPATITIS-C

To determine the virological factors associated with a favorable long- term response to interferon-alpha (IFN) therapy in chronic hepatitis C virus (HCV) infection, 61 Japanese patients with chronic HCV infectio n were treated with IFN for 24 weeks (780 million units in total) and followed for 8 to 16 months after cessation of therapy. Ten patients d ropped out because of severe side effects. Of the 51 patients who comp leted IFN therapy, 23 showed complete and sustained response (CR-->SR) , 13 complete response with early relapse (CR-->Rel), and 15 no respon se to IFN (NR). For the pretreatment serum HCV RNA level, 20/23 who ha d CR-->SR had <10(6) eq/ml compared to 3/13 CR-->Rel and 1/15 NR (P < 0.01). Serologically defined HCV type 2 infection was also associated with a better opportunity to develop CR-->SR compared to CR-->Rel of N R (P < 0.01). Loss of serum HCV RNA at week 4 of IFN therapy was also associated with a more favorable long-term response [17/19 CR-->SR wer e HCV RNA negative compared to 3/11 CR-->Rel (P < 0.01) and 2/13 NR (P < 0.01)]. In contrast, normalization of serum alanine aminotransferas e (ALT) levels at week 4 was found in 9/19 CR-->SR compared to 8/11 CR -->Rel (P = NS), and 0/13 in NR (P < 0.01). Six months after cessation of IFN therapy, 3/25 CR-->SR patients were HCV RNA positive despite n ormalization of serum ALT levels. These data indicated that in additio n to pretreatment serum HCV RNA levels and HCV type, the kinetics of r esponse to IFN (at week 4) were also predictive of subsequent long-ter m response to IFN in patients with chronic HCV infection. (C) 1995 Wil ey-Liss, Inc.