Interferon-alpha treatment of hepatitis C virus-associated mixed cryoglobulinemia

Etiologic treatment of hepatitis C virus-associated mixed cryoglobulinemia

The treatment of mixed cryoglobulinemia (MC) includes several drugs--steroids, cyclosporins, colchicine, plasmapheresis--but given the documented association between MC and hepatitis C virus (HCV), the treatment of choice seems to be antiviral therapy. Several authors have reported the efficacy of interferon (IFN) alpha in the inhibition of HCV replication and reduction of cryoglobulin levels. The therapy with IFN as monotherapy in MC shows a complete response rate in only 10 -12% of cases. Complete response to therapy using a combination of IFN plus ribavirin varies in different studies from 18% to 64% of cases. There are only two studies on the treatment of MC with peginterferon plus ribavirin. Both studies, given the high number of complete responders, reinforce the idea that peginterferon plus ribavirin is, at present, the best available treatment for cryoglobulinemic syndrome. The results obtained with peginterferon combined therapy are superior to standard interferon plus ribavirin in treatment-naive patients. In fact, a sustained virological response was observed in 44% of patients; the same results were obtained for clinical (purpura and arthralgia disappearance) and biochemical (aminotransaminases normalization) responses. New drug combinations, like peginterferons plus anti-CD20 antibodies, should be considered for treatment of MC in the future.

Treatment with peg-interferon alfa-2b and ribavirin of hepatitis C virus-associated mixed cryoglobulinemia: a pilot study

BACKGROUND/AIMS

The aim of this study is to verify the efficacy and safety of peg-interferon alfa-2b in combination with ribavirin for initial treatment of HCV-associated mixed cryoglobulinemia.

METHODS

Eighteen patients (7 women and 11 men) affected by mixed cryoglobulinemia were included in the study and treated with peg-interferon alfa-2b 1.0 microg/kg once a week plus ribavirin (1000 mg daily) for 48 weeks, regardless of the HCV genotype.

RESULTS

At the end of the treatment HCV-RNA became undetectable in 15 patients (83%) and most patients improved clinically. One subject suspended treatment at 13th week due to depression. A large fraction of the patients (8 cases: 44%) relapsed both virologically and clinically a few weeks after the end of therapy. At the end of follow-up, only eight patients (44%) obtained a sustained virological response.

CONCLUSIONS

Peg-interferon alfa-2b in combination with ribavirin seems safe and useful for patients affected by mixed cryoglobulinemia, but not as effective as in patients with HCV-positive chronic hepatitis without cryoglobulinemia.

Cryoglobulinemia

Cryoglobulinemia may be found in a spectrum of disorders spanning clear-cut-B-cell neoplastic states, in which cryoprecipitation manifests as ischemic or occlusive vasculopathy, to a variety of immune complex diseases, in which vasculitis or glomerulonephritis may occur. Symptomatic cryoglobulinemia is many diseases, driven by and driving antibody-antigen responses, hepatic dysfunction, lymphoproliferation, and immune complexes. Distinguishing features that cause only some cryoglobulins to be symptomatic, elucidating the pathogenic mechanisms of HCV in cryoglobulin formation, and devising better therapies and more systematic evaluation of existing therapies are among the challenges for the future. Prognostication and classification will continue to rely on Brouet's classification (types I, II, and III), but additional features will probably include the presence or absence of HCV, HCV factors (genotype, titer), coexisting infections, B-cell clone burden, host factors, and immune system interactions (B- and T-cell idiotype networks, cytokines). Although antiviral therapy is a reasonable option for HCV-associated cryoglobulinemia, not all patients are HCV-positive, and only 60% to 80% of HCV-positive patients respond to IFN. In addition, not all patients tolerate IFN, and in those who do, the response is often short-lived once the treatment is discontinued. Only creative strategies, systematically studied, will provide long-awaited solutions.

[Antiviral treatment of hepatitis C virus infection]

Hepatitis C virus infection is common and almost always chronic and can lead to cirrhosis and hepatocellular cancer. The primary goal of the treatment is virus eradication and the secondary is to reduce inflammation and liver cell damage. Interferon is the only effective therapy but disappearance of the virus is sustained in only 10 to 15%. The factors most closely associated with a response to treatment are absence of cirrhosis, low serum hepatitis C virus RNA level and genotype other than type 1. Recent studies have suggested that interferon treatment may reduce the subsequent risk of hepatocellular carcinoma in responders. The combination of interferon and oral ribavirin therapy increase the sustained response rate to about 40% in initial treatment and 50% for the treatment of relapse. The other therapeutic combination are less well documented. New agents such as hepatitis C virus-specific anti-protease may be available in the next future and treatment is evolving toward multiple-drug regimens.