Management of interferon relapsers

Amantadine therapy for chronic hepatitis C

OBJECTIVE

Although treatment of hepatitis C has improved, up to 50% do not respond to standard therapy with interferon regimes or cannot tolerate the treatment due to side effects. The purpose of the present investigation was to evaluate the safety and effectiveness of the antiviral drug amantadine for the treatment of hepatitis C in those who had either previously failed interferon therapy or were not candidates for interferon.

DESIGN

A prospective double-blind randomized placebo-controlled trial.

SETTING

Outpatient research clinic of a teaching hospital.

PATIENTS/PARTICIPANTS

One hundred fifty-two patients with confirmed hepatitis C with abnormal liver enzymes, detectable hepatitis C RNA in the blood, and abnormal liver histology by biopsy were randomized to receive treatment or placebo.

MEASUREMENTS AND MAIN RESULTS

Patients received either amantadine 100 mg twice daily by mouth or placebo for 6 months. After 6 months, placebo-treated patients were crossed over and treated with amantadine for 6 months and amantadine-treated subjects received 6 additional months of therapy. Amantadine therapy resulted in a significant decline in serum alanine aminotransferase compared to placebo (P =.03). Nine percent cleared the virus at the end of therapy and 6.8% had a sustained virologic response 6 months after discontinuation of amantadine, but this was not statistically significant. Side effects were minimal, and the social quality of life survey improved with 12 months of amantadine (P =.02).

CONCLUSIONS

Oral amantadine may provide a safe alternative treatment for those patients who are intolerant or unresponsive to interferon.

Chronic hepatitis C patients with a post-treatment virological relapse re-treated with an induction dose of 18 MU interferon-alpha in combination with ribavirin and amantadine: a two-arm randomized pilot study

Thirty-seven chronic hepatitis C patients with virological relapse (VR) after previous interferon-alpha (IFN) or IFN/ribavirin (Riba) therapy, were re-treated. Patients were randomized for either IFN/Riba and amantadine (Ama) including a 2-week initial high IFN induction course (18 MU IFN daily) (group A) or the same 2-week IFN induction course combined with Riba/Ama, followed by Riba/Ama without IFN (group B). Treatment duration for both groups was 24 weeks with a 24-week follow-up thereafter. The inclusion in group B was prematurely stopped because all patients (n = 10) relapsed within 2 weeks after stopping IFN. Therefore, all subsequent patients were included in group A (n = 27). In group A, 44% achieved a sustained virological response (SVR) and 29% of the patients with an end-of-treatment virological response had a VR again. Of all pretreatment characteristics, only genotype non-1 patients had a significantly higher chance of achieving SVR (P < 0.001). Of the characteristics during treatment only a negative hepatitis C virus (HCV)-RNA test result in transcription-mediated amplification (TMA) at week 6 had a high predictive value for SVR, 80% in all patients and 92% in genotype non-1 patients. In conclusion, hepatitis C patients with a VR to previous antiviral treatment can be successfully re-treated with IFN induction combined with Riba/Ama for only 6 months, when they have genotype non-1 and a negative HCV-RNA test result in TMA 6 weeks after the start of therapy. Riba/Ama combination therapy without IFN does not prevent VR after 2 weeks high IFN induction.

Limited success of HCV antiviral therapy in United States veterans

OBJECTIVE

The treatment of hepatitis C virus (HCV) infection in United States veterans has become a major task for the Veterans Administration Healthcare System. Although the comprehensive diagnosis and treatment of HCV-infected patients has been mandated, little is known about the performance characteristics of HCV clinics and about the outcomes of antiviral therapy in this unique patient population.

METHODS

We retrospectively examined clinic show rates, treatment eligibility, and the response to antiviral therapy in a dedicated HCV outpatient clinic in a large urban Veterans Affairs medical center.

RESULTS

Our data demonstrate that few veterans--regardless of their age or ethnic background--pursue evaluation and treatment of their HCV infection by hepatologists. A minority of those patients who undergo a comprehensive clinic evaluation meet the standard eligibility criteria for antiviral therapy. The overall efficacy of antiviral treatment, as measured by the sustained virological response rate, is substantially lower than previously reported in randomized clinical trials. HCV-infected veterans are characterized by a unique combination of risk factors that are predictive of a poor response to antiviral therapy, including a preponderance of male gender, HCV genotype I, age > 40 yr, and histologically advanced degrees of liver disease.

CONCLUSIONS

Our study demonstrates the limitations of outpatient HCV treatment initiatives in the United States veteran population, and suggests that the overall impact of current HCV treatment programs may be small.

Analogy of human immunodeficiency virus to hepatitis C virus: the human immunodeficiency model

The human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) for many years overshadowed hepatitis C, which we now know is in some ways an even bigger problem. Important differences also exist between these two viruses and the diseases they cause, and we must be cautious about drawing too close an analogy. However, there are some striking similarities, and many lessons have been learned from HIV research over the past two decades. Parallels with HIV include persistence of the virus, genetic diversity during replication in the host, and the utility of combination treatment that is just now being appreciated with HCV infection. In the last few years, targeted antiviral drugs, such as protease inhibitors, have had an impressive effect on HIV-related morbidity and mortality. Similarities in the HIV and HCV genomes suggest that such drugs may also be useful in treating hepatitis.