A comparison between two induction regimes for the interferon treatment of chronic hepatitis C. Response related factors.

Treatment of chronic hepatitis C with alfa interferon for 6 months achieves sustained responses in 15-25% of the patients. The initial induction with higher doses and the prolongation of treatment can improve the results. A randomized, prospective study was carried out to compare the efficacy of a short term induction schedule of interferon alfa-2b (group A) versus a long term one (group B). 106 patients with chronic hepatitis C were included: 54 received 5 megaunits tiw for 8 weeks and 52 for 16 weeks; afterwards, interferon was reduced to 3 megaunits up to 9 months. The percentage of sustained responses, transient responses and non responses were 18.5%, 24% and 57.4% in group A and 23.1%, 28.8% and 48.1% in group B (NS). The following factors were related to a poor response in the univariate analysis: an increase of serum iron levels, ferritin, Gamma-GT and bilirubin, anti-nuclear antibody positivity, presumed non-parenteral infection, an AST/ALT ratio greater than 0.75, a higher Knodell's index and a greater necrosis and fibrosis score. The multivariate analysis revealed that elevated serum iron and ferritin and anti-nuclear antibody positivity had an independent predictive value related to a non response. Our results appear to suggest that an induction with higher doses and the treatment over nine months are more efficient than the classic schedule. The prolongation of the induction period does not provide additional advantages.

Clinical efficacy of intramuscular human interferon-beta vs interferon-alpha 2b for the treatment of chronic hepatitis C.

We have conducted a randomized study to compare the efficacy and tolerance of human interferon (IFN) beta vs recombinant IFN-alpha 2b in patients with chronic active hepatitis C. Forty patients were included: 21 received IFN-alpha (group A) and 19 IFN-beta (group B). IFN was administered intramuscularly at a dose of 6 MU three times a week (tiw) for 2 months (induction phase), followed by 3 MU tiw for 4 months. Clinical, epidemiological and pathological features were similar in the two groups. Normal alanine aminotransferase (ALT) values at the end of treatment was regarded as a response to therapy and the response rate was 57% (12/21) in group A and 5.2% (1/19) in group B (P < 0.01). Both types of IFN induced a significant decrease in mean ALT values by the end of the induction phase (P < 0.01). When the dose was reduced to 3 MU, a marked, but not significant increase in ALT, was seen in group B, whereas no increase was seen in group A. IFN-beta was better tolerated and haematological adverse effects (platelet and leucocyte decrease) were less pronounced with IFN-beta. Hence, human IFN-beta was less effective than IFN-alpha in treating chronic hepatitis C virus (HCV). Doses of IFN-beta of 3 MU intramuscular (IM) tiw were clearly insufficient and it remains to be established whether higher doses of intramuscularly IFN-beta can be useful.

Treatment of chronic hepatitis C with recombinant interferon alfa-2b for nine months.

This randomised, controlled trial was designed to assess the response to a nine month course of interferon (IFN) alfa-2b, starting with a higher than usual dose. Forty eight patients received IFN 5 million units (MU) three times a week for eight weeks followed by 3 MU three times weekly for seven months; 25 patients in the control group received no treatment. The overall response to treatment was 68.7%, an improvement over other studies, but the high rate of relapse (85% in patients who responded) suggested that a nine month treatment period was insufficient in most cases. Histological improvement was seen in more than 80% of responders to interferon, including a reduction in inflammatory activity, necrosis, and fibrosis.

Response related factors in recombinant interferon alfa-2b treatment of chronic hepatitis C.

In an analysis of the clinical and laboratory variables that can influence the response to interferon alfa-2b treatment, 48 patients with chronic hepatitis C virus infection received interferon 5 million units (MU) subcutaneously three times weekly for eight weeks followed by 3 MU three times weekly for seven months. Response related factors on univariate analysis were found to be age > 40 years, non-parenteral source of infection, pretreatment positive antinuclear antibodies (ANA), cirrhosis, and high serum iron, ferritin, gamma glutamyl transferase, and IgM. An independent predictive value (multivariate analysis) was also found for cirrhosis, ANA, serum iron, and ferritin. A baseline aspartate aminotransferase/alanine aminotransferase ratio of 0.5 and a striking increase during interferon treatment were associated with a complete response.