Abstract

Chronic delta hepatitis is a severe disease with a rapidly progressive course for which currently no effective treatment exists. Treatment with alpha-interferon (alpha-IFN) can inhibit HDV replication and improve serum chemistries in a number of patients. Meta-analysis of five randomized controlled trials using at least 5 MU/m2 of alpha-IFN t.i.w. for a minimum of 3 months showed that alpha-IFN had a statistically significant effect in normalizing ALT values during therapy at a p level of less than 0.001, with a 10.24 odds ratio and a 28.69% risk difference (Mantel-Haentzel-Peto chi 2 = 24.13) but had no significant effect on ALT activity after its discontinuation. From hitherto available results, it appears that the best treatment schedule is a 5 MU standard dose of alpha-IFN given daily (QD) or 9 MU t.i.w. for at least 1 year, which is associated with a remission of the disease in 50-70% of patients. A trial conducted in Greece showed that the mean duration of disease remission under alpha-IFN therapy was 3.8 months per year compared to 1.7 months per year of non-treatment (relative risk = 2.8). Unlike hepatitis B, no factors predictive of the response to alpha-IFN therapy have been identified except, perhaps, for the duration of the disease. No adjuvants have been found to enhance the efficacy of alpha-IFN treatment and no therapeutic alternatives are available at present. Advances in understanding HDV replication and the pathogenetic mechanisms in chronic delta hepatitis may bring about significant improvement in its therapy in the future.