C型慢性肝炎に対するインターフェロン療法に関する研究

投与方法および効果判定の検討

抄録

The difference in response rate to interferon (IFN) among several treatment regimens was assessed retrospectively in 48 HCV-RNA positive patients with chronic hepatitis C. The study focused on patients' pretreatment profiles and response to treatment, histological findings before and after the treatment and the significance of HCV-RNA detection in evaluating the outcome.
A complete response (CR) evaluated by the outcome of alanine aminotransferase (ALT) was obtained in 16 of 25 patients (64.0%) treated with IFN in doses of 3 to 6 million units daily for the first 4 or 8 wks and subsequent dosing twice or three times weekly for the following 8 to 146 wks. In contrast, CR was obtained in only 7 of 16 patients (43.8%) treated with the regimen in which patients received IFN in doses of 1 to 6 million units daily for 4 to 8 wks and no subsequent IFN. In comparing the responders to IFN (25 cases) and the non responders (19 cases), there were no significant differences regarding patients' age, sex, the presence or absence of history of blood transfusion, pretreatment ALT values or histological magnitude, or total doses of IFN administered. When the basal and final biopsy samples were compared, Knodell's index of histological activity had decreased significantly in the responders but not in the non responders. In 24 of the 25 responders, HCV-RNA had disappeared from their serum at the end of treatment, and in 23 it remained undetectable 6 months after treatment. In contrast, in 6 of the 19 non responders HCV-RNA had become negative at the end of treatment but was detectable in all cases 6 months after treatment.
Thus, it is concluded that (1) a regimen of daily administration for the first 4 or 8 wks with subsequent dosing twice or three times weekly was preferable in terms of obtaining frequent CR, (2) response to IFN cannot be predicted by a patient's pretreatment profile, (3) in responders, histological activity decreases, and (4) in responders, HCV-RNA becomes undetectable not only at the end of treatment but also 6 months after treatment.