Interferon alfa en el tratamiento de la hepatitis cronica C: curso de 24 versus 48 semanas. Resultados de un estudio randomizado / Interferon alfa in the treatment of chronic hepatitis C: course of 24 versus 48 weeks. Results of a randomized trial

RESUMO

The aim of this trial was to investigate if a more prolonged course of interferon (IFN) is able to increase the long-term benefit in patients with chronic hepatitis C. Forty-four patients with active chronic hepatitis and antibodies to HCV were randomly assigned to receive IFN-alfa 2b 3 MU t.i.w. during 24 weeks (group I, n 23) or during 48 weeks (group II, n 21). In the evaluation of results, complete response was considered when the ALT values returned to normality during the treatment; and sustained response, when the ALT values persisted below normal range during at least 6 months post therapy. Histologic changes were compared by using the Histological Activity Index, or Knodell score. Viremia status was evaluated for the study of HCV RNA (by nested-RT-PCR). Results: There were no significant differences between boths groups before treatment, in terms of age, sex, ALT, or histologic findings (11 patients in group I, and 7 in group II had cirrhosis). Complete response was found in 9 patients (39.1 per cent) from group I; in 11 (52.4 per cent) from group II (NS). Basal histologic findings were identified as the only predictive factor of complete and sustained response, by logistic regresion analysis. Considering only noncirrhotic patients, complete response was seen in 58.3 per cent in patients from group I, 71.4 per cent in group II. Sustained response was obtained in 4 patients from group I, (17.4 per cent), 7 from group II (33.3 per cent) (NS). Post IFN liver biopsies were performed in 23 patients (12 from group I, 11 from group II). In group I patients, there were no significant changes. In group II, Knodell score was found to be significantly decreased post IFN (pre IFN, median 10, range 3-15; post IFN, median 6, range 2-14) (p<0.05). HCR RNA was absent in serum during the follow-up post IFN in 2 patients from group I, in 3 from group II. The results of this study show that a 48 weeks course of IFN has a trend to achieve a higher sustained response than the usual regime (but non significant); and it produces a decrease in the histologic activity. The best predicitve factor of positive response was the absence of cirrhosis in our study (although we did not evaluate viral factors, such as genotypes or HCV viremia levels).