Pilot study of interferon gamma for chronic hepatitis C

Background/Aims: Currently, there are no effective therapies available for patients with chronic hepatitis C who have failed to respond to optimal interferon alfa-based regimens. The aims of this pilot study were to assess the antiviral activity and safety of interferon gamma in chronic hepatitis C. Methods: Patients with chronic hepatitis C, genotype 1, who had not responded to or who had relapsed after therapy with interferon alfa and ribavirin were enrolled in a trial of interferon gamma 1b given in doses of 100, 200 or 400 μg subcutaneously three times weekly for 4 weeks. Frequent blood samples were obtained for HCV RNA levels. Results: Fourteen patients were enrolled. Geometric mean HCV RNA levels remained unchanged. Serum aminotransferase levels also did not change, while there were significant decreases in neutrophil counts (-41% from baseline) and hematocrit (-5%). Low grade fever and malaise were common with the first injection of interferon gamma, but no serious side effects were encountered. Conclusions: Although relatively well tolerated, interferon gamma in doses of 100-400 μg thrice weekly had no effect on HCV RNA levels in patients with chronic hepatitis C who had failed to achieve a sustained response to interferon alfa-based therapies.