The combination therapy of interferon and amantadine hydrochloride for patients with chronic hepatitis C

The effect of interferon treatment for chronic hepatitis C patients with genotype 1b virus has been suboptimal. We studied the effect of the combination therapy of interferon and amantadine on patients with a high serum viral load of genotype 1b virus.

We studied the virological response of naive chronic hepatitis C patients with a high viral load of genotype 1b virus (4.5 log copies/50 microL or 100 kcopies/mL and higher) during interferon and amantadine administration for 6 months and 6 months after the end of treatment. Twenty patients were treated with interferon alone (natural interferon-beta 6 MU daily for 6 weeks and thrice-a-week for 20 weeks) for 26 weeks. Eleven patients were treated with the combination therapy of interferon and amantadine hydrochloride (100 mg orally daily) for 26 weeks.

After daily administration of interferon-beta intravenously once a day for 6 weeks, all patients showed the negative tests of serum HCV-RNA by polymerase-chain-reaction methods by the combination therapy, while 13 patients (65.0%) showed the negative tests by interferon alone (p = 0.0257). At the end of treatment, serum HCV-RNA were not detected in 54.5% of patients treated with interferon and amantadine, while it was detected in 50.0% of patients treated with interferon alone. At 6 months follow-up, only one patient (9.1%) could eradicate HCV-RNA in patients with interferon and amantadine, while no patient could with interferon monotherapy (not significantly).

Amantadine hydrochloride has the additive effects to interferon treatment on the virological responses of serum HCV-RNA during a co-administration, although the combination therapy has not shown a significantly promising effect on the eradication of HCV-RNA in the patients with chronic hepatitis C with a high viral load of genotype 1b virus.