Amantadine-HCL in the treatment of chronic hepatitis C in non-responders to alpha-interferon. Effect on ALT serum levels and viral load

Due to the limited efficacy of alpha-interferon for chronic hepatitis C amantadine has been proposed as a possible alternative method of treatment. However, few studies about efficacy of amantadine in chronic hepatitis C are available with controversial results. Stimulated by recent data in the literature, we studied the effect of 100 mg of amantadine HCL (alone) PO bid, for a four month period on alanine aminotransferase serum levels and viral load in a cohort of 18 patients (14 males and 4 females) with chronic hepatitis C, non-responders to alpha-interferon. Inclusion criteria were: detectable serum HCV-RNA, alanine aminotransferase above the upper limit of normal, chronic inflammation on liver biopsy, no other associated chronic liver disease and written informed consent. Available biopsies showed initially four cases of cirrhosis, six of chronic persistent hepatitis and eight of chronic active hepatitis. The most prevalent HCV genotypes were 3a (n = 9, 52.94%) and 1b (n = 6, 32.29%). Viral load (Amplicor HCV Monitor, Roche, USA) and alanine aminotransferase levels were obtained at baseline and after four months of treatment. All patients enrolled into the study but one completed the treatment. One patient discontinued amantadine due to severe depression. No significant reduction was observed between baseline and final values of alanine aminotransferase (139.118 +/- 79.789 vs. 99.588 +/- 62.583 U/L, P = 0.059) and viral load (7.154 +/- 1.596 vs. 6.574 +/- 1.584 log copies/mL, P = 0.147). Amantadine alone was not effective neither eradicating viremia nor normalizing alanine aminotransferase levels in chronic hepatitis C non-responders to alpha-interferon patients. It is suggested that only a study with amantadine alone in-patients without previous treatments could determine its efficacy in comparison with alpha-interferon.