Activity and tolerance of a continuous subcutaneous infusion of interferon-alpha2b in patients with chronic hepatitis C.

We administered interferon-alpha2b (IFN-alpha2b) by continuous subcutaneous infusion (60,000 IU/h, or 10 million IU/week) over 3 months to 7 patients with chronic hepatitis C. All had previously responded, as assessed by normalization of transaminases to the same dose of IFN administered by intermittent injection over 6 months, but had relapsed after cessation of therapy. The continuous infusion was tolerated well at the site of infusion, and the systemic side effects were similar in type but were lesser in intensity than with intermittent dosage. Four of 7 subjects had normalization of transaminase at the end of week 12 of therapy. Serum HCV RNA and HCV by PCR decreased with treatment, and there was a prompt and sustained increase in serum beta2-microglobulin and of 2', 5' OAS activity. The level of the latter appeared to correlate with response of the transaminase. Serum IFN concentrations were low but detectable throughout therapy. After stopping IFN administration, the transaminases in responders increased again to pretreatment levels.