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    Association Between Level of Hepatitis D Virus RNA at Week 24 of Pegylated Interferon Therapy and Outcome
    (Elsevier Science Inc, 2015) Keskin, Onur; Wedemeyer, Heiner; Tuzun, Ali; Zachou, Kalliopi; Deda, Xheni; Dalekos, George N.; Heidrich, Benjamin
    BACKGROUND & AIMS: Interferon is the only effective treatment for chronic hepatitis D virus (HDV) infection. No rules have been set for stopping treatment based on viral kinetics. We analyzed data from an international study of hepatitis D treatment to identify factors associated with outcomes of pegylated interferon treatment, with and without adefovir. METHODS: We analyzed data from the Hep-Net-International Delta Hepatitis Intervention Trial on 50 patients with compensated liver disease who tested positive for anti-HDV and HDV RNA. Subjects received pegylated interferon alpha 2a, with adefovir or placebo, or only adefovir, for 48 weeks. Twenty-four weeks after treatment ended, 41 patients were evaluated for levels of HDV RNA and DNA, liver enzymes, and hepatitis B surface antigen (HBsAg); liver biopsy specimens were analyzed for fibrosis. Response to therapy was defined as end-of-treatment response or post-treatment week 24 virologic response. In both cases virologic response was associated with undetectable HDV RNA levels. Patients with less than a 1 log decrease in HDV RNA at the end of treatment were considered null responders. RESULTS: Based on univariate and multivariate analysis, the level of HDV RNA at week 24 of treatment was associated more strongly with response to therapy than other factors analyzed. The level of HBsAg at week 24 of treatment was associated with a response to therapy only in univariate analysis. Lack of HDV RNA at week 24 of treatment, or end of treatment, identified responders with positive predicted values of 71% and 100%, respectively. At 24 weeks after treatment, a decrease in HDV RNA level of less than 1 log, combined with no decrease in HBsAg level, identified null responders with a positive predictive value of 83%. A decrease in HDV RNA level of more than 2 log at week 24 of treatment identified null responders with a negative predictive value of 95%. CONCLUSIONS: Based on an analysis of data from a large clinical trial, the level of HDV RNA at week 24 of treatment with pegylated interferon, with or without adefovir for 48 weeks, can identify patients who will test negative for HDV RNA 24 weeks after the end of treatment. This information can be used to help physicians manage patients receiving therapy for chronic hepatitis D.
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    Can response to pegylated interferon treatment in chronic delta hepatitis be predicted with on-treatment parameters?
    (Wiley-Blackwell, 2012) Onder, Fatih Oguz; Erhardt, Andreas; Idilman, Ramazan; Keskin, Onur; Dalekos, George N.; Yalcin, Kendal; Manns, Michael P.
    [Abstract Not Available]
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    Role of immunohistochemistry for hepatitis D and hepatitis B virus in hepatitis delta
    (WILEY-BLACKWELL, 111 RIVER ST, HOBOKEN 07030-5774, NJ USA, 2014) Kabaçam, Gökhan; Wedemeyer, Heiner; Savaş, Berna; Dalekos, George; Tabak, Fehmi; İdilman, Ramazan; Erhardt, Andreas; Yalçın, Kendal; Bozdayı, Mithat A.; Bozkaya, Hakan; Manns, Michael; Dienes, Hans; Yurdaydın, Cihan; Keskin, Onur
    Background & Aims: Immunohistochemical assessment of liver tissue in chronic delta hepatitis (CDH) is underinvestigated. Aim of the study was (i) to assess variables associated with hepatitis D antigen (HDAg), hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) staining in the liver. Methods: Demographic, biochemical and virologic data collected from the HIDIT 1 study were used. HBsAg, HBcAg and HDAg immunohistochemical (IHC) staining was semiquantitatively assessed. Results: Hepatitis D antigen immunohistochemical staining displayed positive correlations with age and alanine aminotransferase (ALT) and negative correlations with serum HBsAg (P = 0.01 for all). HBsAg IHC displayed a negative correlation with gamma glutamyl transferase and positive correlations with serum HBV DNA, serum HBsAg levels and HBeAg serology (P < 0.001, P = 0.02 and P = 0.007 respectively). HBcAg staining was mainly nuclear and displayed negative correlations with serum HBsAg and histologic activity (P = 0.002 and P = 0.02 respectively). Pegylated IFN based treatment led to a decline of all IHC markers, however, these markers had no impact on treatment outcome. Conclusions: These data suggest an association of liver injury with HDAg expression in CDH whereas the negative correlation between HBcAg expression and liver injury and the overall nuclear localization of HBcAg suggest that HBcAg does not contribute to liver injury in CDH. HDV cases with high level of HBV replication, high serum HBsAg levels, HBeAg positivity, that are probably in the earlier stages of disease (low gamma-glutamyl transferase), had a more intense HBsAg staining profile. Overall, the data enforce the importance of HDAg and HBsAg in different phases of CDH infection.