We have followed up 44 patients with chronical viral Delta hepatitis. All the patients underwent a clinical, hematologic, biochemical and an immunologic examinations; quantitative determination of HBV DNA through PCR and HDV RNA and instrumental determination. It was revealed that cytolysis prevailed in the cases of the majority of patients, as compared to the cholestasis. The PegInterferon alfa 2a or alfa 2b therapy (duration ≥48 weeks) was performed in the cases of 44% of the immunologically assessed patients. Analyzing the post-therapy indices of the humoral immune status of the patients compared with the native ones, no real differences between the values of IgM, IgG and IgE and the T-lymphocyte line were identified in these two evolutionary periods. The antiviral treatment's success rate in cases of patients with chronic viral Delta hepatitis is reduced (about 25% of patients are efficiently treated), a fact that suggests the necessity of a new therapy option for these patients.