Interleukin-28 gene polymorphisms may contribute to HBsAg persistence and the development of HBeAg-negative chronic hepatitis B.

BACKGROUND & AIMS: Aim of this study was to investigate whether a potential association exists between several single nucleotide polymorphisms (SNPs) of the IL-28B gene (rs12979860, rs1188122, rs8099917, rs8105790, rs12980275) and HBsAg persistence. Further, a potential effect on the development of HBeAg-negative CHB vs. inactive HBsAg carrier state was assessed in a genotype D HBV cohort. A cohort of chronic HDV patients was also used to see if they behave differently compared to chronic HBV patients. METHODS: This study was conducted in three main patient cohorts: Group 1 consisted of 482 patients with HBsAg persistence. Of them 143 were inactive carriers, 94 had HBeAg-positive chronic hepatitis B (CHB) and 245 had anti-HBe-positive CHB. Group 2 represents spontaneously recovered HBV patients; they were anti-HBs and anti-HBc positive. Group 3 consisted of 176 chronic hepatitis delta (CHD) patients with antidelta and HDV-RNA positivity. DNA sequencing was performed for genotyping. RESULTS: When patients with HBsAg persistence were compared with spontaneously recovered patients, a significant difference was observed for rs8105790 (P < 0.0001), rs12980275 (P < 0.02). Patients who had the CC/TC genotype for rs8105790 (P < 0.0001) and AA genotype for 1188122 (P < 0.02) were more likely to be inactive HBsAg carriers, when inactive HBsAg carriers were compared with HBeAg-negative CHB patients. Comparison of CHD patients vs. recovered HBV patients was parallel to that of HBV persistence vs. recovered HBV with similar significant differences in same SNPs. CONCLUSION: These results suggest that IL-28B polymorphisms may contribute to HBsAg persistence and the development of the inactive HBsAg carrier state.

Clonal analysis of the quasispecies of antiviral-resistant HBV genomes in patients with entecavir resistance during rescue treatment and successful treatment of entecavir resistance with tenofovir.

BACKGROUND: Clonal analysis of quasispecies of resistant HBV genomes in patients with entecavir (ETV) resistance receiving lamivudine (3TC) plus adefovir (ADV) rescue therapy has never been performed. METHODS: A sample of 10 patients with ETV resistance who were switched to 3TC+ADV treatment were analysed for changes in viral quasispecies. Serum samples at baseline, and at months 3 and 6 of 3TC+ADV treatment could be clonally analysed in 7 of 10 patients; 3-82 clones per sample (total 1,068 clones, mean 63) were sequenced. RESULTS: 3TC+ADV therapy led to a modest decline in HBV DNA. Almost all clones had L180M and M204V 3TC resistance mutations before and during combination therapy. All clones had ≥1 of the S202G, T184F, T184A, T184L, T184I and M250V ETV resistance mutations. The percentages of detected clones bearing 3TC (rtL180M and rtM204V) and ETV mutations did not change with rescue 3TC+ADV therapy. In 7 of 8 patients with detectable HBV DNA (median 5.17 log(10) copies/ml) after a median 24 months of ADV therapy, HBV DNA became undetectable with 3TC plus tenofovir after 6 months of treatment. CONCLUSIONS: In patients with ETV resistance tenofovir is effective. Clonal analysis data indicate no selection of specific HBV mutants during rescue 3TC+ADV.

Entecavir treatment of chronic hepatitis D.

BACKGROUND: Hepatitis D virus (HDV) requires hepatitis B surface antigen (HBsAg) to propagate infection and cause disease. Entecavir is a nucleoside analog with potent antiviral efficacy, and in the woodchuck animal model it also decreased hepatitis B virus (HBV) cccDNA and woodchuck surface antigen. The aim of this study was to investigate the efficacy of entecavir in chronic hepatitis D (CHD). METHODS: This single-center study was conducted in patients with compensated liver disease. All patients had to have detectable hepatitis HDV RNA and elevated levels of alanine aminotransferase (ALT). Entecavir was given at a dosage of 1 mg/d for 1 year. The primary end point was achievement of undetectable HDV RNA at the end of treatment. RESULTS: Thirteen consecutive patients were assessed. All patients had detectable HDV RNA, and 8 had detectable HBV DNA at baseline. At the end of treatment, HBV DNA became undetectable in all patients (P = .001). No significant decline in HDV RNA, ALT, or quantitative HBsAg levels was observed. The primary end point of undetectable HDV RNA at the end of treatment was achieved in 3 patients who had significantly lower baseline HDV RNA levels than nonresponders (2.99 log(10) copies/mL ± .70 vs 4.68 ± .97; P = .0185). In all 3 patients, ALT levels were also normal at the end of treatment. CONCLUSIONS: One year of entecavir treatment is ineffective in CHD. Any generalized beneficial effect of nucleoside/nucleotide analog treatment may necessitate prolonged treatment. Patients with CHD with HBV dominance, which is likely to occur in the later phases of CHD, may be a reasonable patient cohort in which to target nucleoside/nucleotide analog therapy.

Molecular characterization of a novel entecavir mutation pattern isolated from a multi-drug refractory patient with chronic hepatitis B infection.

BACKGROUND: Prolonged antiviral treatment results in selection and accumulation of resistant strains in quasispecies pool in hepatitis B virus (HBV) infection. OBJECTIVES: The aim of this study was to characterise a novel HBV pattern which shows resistance to lamivudine, adefovir dipivoxil and entecavir using in vitro phenoyping assay. STUDY DESIGN: A male 36 years old patient diagnosed with anti HBe-positive chronic hepatitis B (CHB) had received lamivudine treatment for 7 years following an initial unsuccessfull interferon treatment. The therapy had been switched to adefovir and then to entecavir when breakthrough occcured during each treatment. This led only to a temporary HBV DNA decline which soon was followed by viral breakthrough despite the lack of known entecavir resistance mutations. Patient died after 9 months of entecavir treatment from liver failure. A total of 434 clones from 6 different serum samples were analysed retrospectively. HBV genomes bearing mutation patterns suggestive of antiviral resistance were analysed by in vitro phenotyping assay. RESULTS: Dominance of a clone carrying L80LV, L91I, M204I, S219A, N238D, Y245H changes was detected in the last serum sample of the patient just before his death. This pattern displayed 30.4 fold resistance to entecavir when compared with the wild type HBV by in vitro phenotyping assay. CONCLUSION: A novel mutation pattern showing a high degree of resistance to entecavir was documented. In this pattern, the S219A and Y245H mutations mainly seem to contribute to the emergence of ETV resistance.