Long-term intermittent administration of interferon-alpha in patients with chronic non-A, non-B hepatitis.

IFN-alpha was administered intermittently over a 6 month period in 39 patients with chronic non-A, non-B hepatitis confirmed by peritoneoscopy and liver biopsy. Three million units of IFN-alpha were administered 3 times a week for the first 6 months then twice, then once a week. In 26 patients (67%), GPT decreased and remained within the normal range during the course of administration, and in 9 patients (23%) GPT remained normal for over 6 months after the discontinuation of IFN-alpha. There was no significant difference of efficacy among 3 groups liver histology groups (CPH, CAH-2A, and CAH-2B), but GPT decreased significantly in patients with sporadic hepatitis compared to patients with a history of blood transfusion. Furthermore, GPT decreased significantly in patients with a history of a blood transfusion within the preceding 2 years compared to patients with a history of a blood transfusion over 7 years ago. GPT increased markedly after an early tapering to 2 doses weekly, but it did not increase after a 6 month administration. In conclusion, the long-term administration of 300 million unit IFN-alpha, 3 times weekly for 6 months, about 2.5 hundred million units in total, is thought to be an effective way to control chronic NANB hepatitis.