Chronic hepatitis C

Interferon Therapy in Liver Cirrhosis Type C

Objective:

To review current information on the role of interferon (IFN) therapy in patients with liver cirrhosis type C.

Data Sources:

All relevant articles from 1989 to December 1998 were identified by a MEDLINE search using the terms interferon treatment and liver cirrhosis. Some studies were identified from bibliographies of selected articles.

Study Selection:

More than 97 articles were identified. Reports were included if they contained new or relevant information on the hepatitis C virus (HCV), IFN therapy in liver fibrosis and cirrhosis, outcome of cirrhosis, hepatocellular carcinoma (HCC), or adverse effects related to IFN. Abstracts were included only when they added information not otherwise available in the literature.

Data Synthesis:

Response to IFN is unfavorably influenced by the presence of cirrhosis; there are several other predictors of response. IFN therapy can decrease the risk of development of HCC in some patients. In patients with compensated cirrhosis type C, a higher dosage of IFN-alfa and longer duration of therapy are associated with a better response. Combined therapy with IFN-alfa 2b and ribavirin is more effective than therapy with IFN-alfa alone. Therapy with human lymphoblastoid IFN (L-IFN) produces sustained response rates equivalent to those of recombinant IFN-alfa. Consensus IFN (CIFN) is more effective than IFN-alfa 2b. Larger dosages of CIFN are associated with better results. Normal alanine transaminase concentration and the absence of serum HCV RNA after treatment and again after 24 weeks of observation indicate a successful end point of IFN therapy. Adverse effects related to IFN treatment are usually minor.

Conclusions:

Although the presence of cirrhosis predicts a poor response to IFN treatment, some patients benefit from this therapy. Reasonable treatment regimens for patients with compensated HCV cirrhosis include IFN-alfa therapy, 6 MU subcutaneously three times weekly for 12 months, L-IFN 3 MU intramuscularly three times weekly for six months, or CIFN 9 or 12 μg subcutaneously three times weekly for six months. Patients receiving IFN should be seen every two to four weeks, with frequent monitoring of complete blood count and serum transaminase concentrations.

Treatment of chronic hepatitis C virus infection with recombinant consensus interferon

To assess the safety and efficacy of consensus interferon (IFN-Con-1), 55 patients with chronic hepatitis C infection were treated with either 3, 6, 9, 12, or 15 microg IFN-Con-1 s.c. three times a week for 24 weeks, followed by 24 weeks of observation. There was a dose-response relationship with respect to the number of patients with normalized ALT concentrations or undetectable HCV RNA. At the end of the 24-week treatment period, the serum ALT had normalized in 18% of patients given the 3 microg dose and 42% of patients given the 12 microg or 15 microg doses of IFN-Con-1. At the end of the posttreatment observation period, the serum ALT was still normal in 10% of patients given the 3 microg, 6 microg, or 9 microg doses and in 50% of patients given the 15 microg dose. Also, at the end of the 24-week treatment period, 27% of patients given the 3 microg dose and 75% given the 15 microg dose had undetectable serum HCV RNA. At the end of the posttreatment observation period, the proportion of patients with undetectable HCV RNA ranged from 9% of those given the 3 microg dose to 50% of those given the 15 microg dose. Our study indicates that treatment with IFN-Con-1 appears to be safe and effective. In addition, use of 15 microg of IFN-Con-1 resulted in significantly more patients with sustained ALT normalization and absence of HCV RNA 6 months after cessation of therapy compared with treatment with lower doses of IFN-Con-1. Additional trials are underway to confirm these findings.