Background: Until very recently, interferon (INF) in Spain was authorized in chronic hepatitis C (C-HCV) at a dosis of 3 megaunits (mu) for 6 months. Nonetheless, the rate of maintained complete response is lower than that obtained with more prolonged treatments. The first aim of this study was to retrospectively know the effectiveness of alpha INF in patients treated for 6 or 12 months with a dosis of 3 or 5-6 MU. The second was to analyze the characteristics of the patients who achieved a maintained complete response.
Patients and methods: Patients with C-HCV treated in 9 hospitals in Andalucía, Spain who fulfilled the following conditions were retrospectively analyzed: liver biopsy prior to treatment, positive test for anti HCV and a follow up of at least 6 months after alpha INF treatment. A total of 344 patients were studied: 267 treated with alpha INF-2b, 51 with alpha INF-2a and 26 with lymphoblastoid INF. One hundred ninety-five patients were treated for 6 months and 149 for 12 months.
Results: Seventy-seven (22%) of the patients presented maintained complete response, 170 (50%) did not respond and 97 (28%) relapsed. On comparing the three types of interferon used over 6 months, no significant differences were observed. Neither were differences found on comparing the dosis of 3 mu versus 5 or 6 mu. On analyzing the treatments of 6 and 12 months, the following was observed, respectively: maintained complete response 15% vs 32%, relapse 29% vs 30% and non responders 57% vs 38% (p < 0.001). Multivariate analysis demonstrated that the patients who responded the best to INF were those who presented the following characteristics: female sex, age under 40 years last, history of transfusion or IVDA, basal GPT level higher than 145 IU/I, GGT less than 55 IU/I, less evolved histologic lesions and duration of treatment over 12 months.
Conclusions: Of the different treatments analyzed with alpha interferon in chronic hepatitis C, the best was found to be that with 3 mu during 12 months.