No abstract

We examined the efficacy of decreasing high doses (beginning at 18 MU/day) of interferon-alpha 2a vs. that of daily low doses (3 MU) in the treatment of chronic hepatitis delta virus infection. Patients treated with 18 MU had a somewhat higher frequency of normalization of serum ALT levels than patients treated with low doses (31% and 12%, respectively, on an intention-to-treat basis). A decrease in the percentage of hepatitis D virus RNA positivity was observed in both groups at the end of treatment. Thus, whereas in baseline samples 10 (62%) of the patients in each group were positive for hepatitis D virus RNA in serum on slot-blot hybridization, these numbers decreased to 5 (31%) and 4 (25%) patients in groups 1 and 2, respectively, at the end of therapy. However, hepatitis D virus RNA, detected by means of nested polymerase chain reaction, remained in all but two (one in each group) patients who completed the treatment. Finally, during posttreatment follow-up, hepatitis D virus RNA levels returned to baseline values, and only one patient remained negative for this marker. The beneficial effect of interferon-alpha was only transient. Only two patients (one from each treatment group) had persistently normal serum ALT levels after 18 mo of follow-up. Finally, the presence of serum hepatitis D virus RNA at the end of therapy, detected with nested polymerase chain reaction, might be a good marker for the prediction of viral replication relapse.

We compared the response and the relapse rates of HBeAb-positive patients treated with interferon-alpha for 6 or 12 months. Thirty-eight HBeAb-positive patients which chronic hepatitis B were randomly allocated into two groups: Group I (19 patients receiving 10 MU of recombinant interferon-alpha 2b three times a week for 2 months, followed by 5 MU three times a week for 2 months and then 3 MU three times a week for 2 months); Group II (19 patients receiving 10 MU of recombinant interferon-alpha 2b three times a week for 2 months, followed by 5 MU three times a week for 2 months and then 3 MU three times a week for 8 months). At the end of treatment, alanine aminotransferase normalization was higher but not more significant in Group I than in II (53% vs 26%), while hepatitis B virus DNA clearance was similar in both groups (21% in Group I vs 26% in Group II). However, at 12 months of follow-up, biochemical relapses occurred only in Group I (60% vs 0% in Groups I and II, respectively). Five complete responders cleared hepatitis B surface antigen at that time. In conclusion, prolonged treatment of HBeAb patients is efficient in reducing the biochemical relapse.

MxA protein is interferon inducible, and its role as an antiviral mediator is being studied in various viral diseases. Several cytokines, including type 1 interferons (alpha and beta), interleukins 2 and 12, and granulocyte, macrophage, and granulocyte-macrophage colony-stimulating factors, were tested for their ability to induce human MxA protein synthesis in peripheral blood mononuclear cells from 15 chronic hepatitis B virus-infected patients and 6 healthy subjects as controls. Constitutive MxA expression was scarce in patients and controls but increased significantly in response to type I interferons. MxA responsiveness to interferon alpha was diminished significantly in chronic hepatitis B patients, compared with healthy donors (P < 0.05); this effect was more marked in patients with high viremia levels. Interleukins 2 and 12, and none of the colony-stimulating factors tested, induced low, but detectable, MxA protein levels. These results indicate that chronic infection by hepatitis B virus may impair activation of the immune cells and their capacity to respond to type 1 interferons.