Understanding Hepatitis B Virus Dynamics and the Antiviral Effect of Interferon Alpha Treatment in Humanized Chimeric Mice.

Whereas the mode of action of lamivudine (LAM) against hepatitis B virus (HBV) is well established, the inhibition mechanism(s) of interferon alpha (IFN-α) is less completely defined. To advance our understanding, we mathematically modeled HBV kinetics during 14-day pegylated IFN-α-2a (pegIFN), LAM, or pegIFN-plus-LAM (pegIFN+LAM) treatment of 39 chronically HBV-infected humanized uPA/SCID chimeric mice. Serum HBV DNA and intracellular HBV DNA were measured frequently. We developed a multicompartmental mathematical model and simultaneously fit it to the serum and intracellular HBV DNA data. Unexpectedly, even in the absence of an adaptive immune response, a biphasic decline in serum HBV DNA and intracellular HBV DNA was observed in response to all treatments. Kinetic analysis and modeling indicate that the first phase represents inhibition of intracellular HBV DNA synthesis and secretion, which was similar under all treatments with an overall mean efficacy of 98%. In contrast, there were distinct differences in HBV decline during the second phase, which was accounted for in the model by a time-dependent inhibition of intracellular HBV DNA synthesis, with the steepest decline observed during pegIFN+LAM treatment (1.28/day) and the slowest (0.1/day) during pegIFN monotherapy. Reminiscent of observations in patients treated with pegIFN and/or LAM, a biphasic HBV decline was observed in treated humanized mice in the absence of an adaptive immune response. Interestingly, combination treatment did not increase the initial inhibition of HBV production but rather enhanced second-phase decline, providing insight into the dynamics of HBV treatment response and the mode of action of IFN-α against HBV. IMPORTANCE Chronic hepatitis B virus (HBV) infection remains a global health care problem, as we lack sufficient curative treatment options. Elucidating the dynamics of HBV infection and treatment response at the molecular level could facilitate the development of novel, more effective HBV antivirals. Currently, the only well-established small animal HBV infection model available is the chimeric uPA/SCID mice with humanized livers; however, the HBV inhibition kinetics under pegylated IFN-α-2a (pegIFN) in this model system have not been determined in sufficient detail. In this study, viral kinetics in 39 humanized mice treated with pegIFN and/or lamivudine were monitored and analyzed using a mathematical modeling approach. We found that the main mode of action of IFN-α is blocking HBV DNA synthesis and that the majority of synthesized HBV DNA is secreted. Our study provides novel insights into HBV DNA dynamics within infected human hepatocytes.

Persistent Loss of Hepatitis B Virus Markers in Serum without Cellular Immunity by Combination of Peginterferon and Entecavir Therapy in Humanized Mice.

Nucleot(s)ide analogues and peginterferon (PEG-IFN) treatment are the only approved therapies for chronic hepatitis B virus (HBV) infection. However, complete eradication of the virus, as indicated by persistent loss of hepatitis B surface antigen (HBsAg), is rare among treated patients. This is due to long-term persistence of the HBV genome in infected hepatocytes in the form of covalently closed circular DNA (cccDNA). In this study, we investigated whether administration of a large dose of a nucleoside analogue in combination with PEG-IFN can achieve long-term loss of HBsAg in human hepatocyte chimeric mice. Mice were treated with a high dose of entecavir and/or PEG-IFN for 6 weeks. High-dose combination therapy with both drugs resulted in persistently negative HBV DNA in serum. Although small amounts of HBV DNA and cccDNA (0.1 and 0.01 copy/cell, respectively) remained in the mouse livers, some of the mice remained persistently negative for serum HBV DNA at 13 weeks after cessation of the therapy. Serum HBsAg and hepatitis B core-related antigen (HBcrAg) continued to decrease and eventually became negative at 12 weeks after cessation of the therapy. Analysis of the HBV genome in treated mice showed accumulation of G-to-A hypermutation and CpG III island methylation. Persistent loss of serum HBV DNA and loss of HBV markers by high-dose entecavir and PEG-IFN combination treatment in chimeric mice suggests that control of HBV can be achieved even in the absence of a cellular immune response.

Development of a Novel Site-Specific Pegylated Interferon Beta for Antiviral Therapy of Chronic Hepatitis B Virus.

Although nucleot(s)ide analogues and pegylated interferon alpha 2a (PEG-IFN-α2a) can suppress hepatitis B virus (HBV) replication, it is difficult to achieve complete HBV elimination from hepatocytes. A novel site-specific pegylated recombinant human IFN-ß (TRK-560) was recently developed. In the present study, we evaluated the antiviral effects of TRK-560 on HBV replication in vitro and in vivo. In vitro and in vivo HBV replication models were treated with antivirals including TRK-560, and changes in HBV markers were evaluated. To analyze antiviral mechanisms, cDNA microarray analysis and an enzyme-linked immunoassay (ELISA) were performed. TRK-560 significantly suppressed the production of intracellular HBV replication intermediates and extracellular HBV surface antigen (HBsAg) (P < 0.001 and P < 0.001, respectively), and the antiviral effects of TRK-560 were enhanced in combination with nucleot(s)ide analogues, such as entecavir and tenofovir disoproxil fumarate. The reduction in HBV DNA levels by TRK-560 treatment was significantly higher than that by PEG-IFN-α2a treatment both in vitro and in vivo (P = 0.004 and P = 0.046, respectively), and intracellular HBV covalently closed circular DNA (cccDNA) reduction by TRK-560 treatment was also significantly higher than that by PEG-IFN-α2a treatment in vivo (P = 0.0495). cDNA microarrays and ELISA for CXCL10 production revealed significant differences between TRK-560 and PEG-IFN-α2a in the induction potency of interferon-stimulated genes. TRK-560 shows a stronger antiviral potency via higher induction of interferon-stimulated genes and stronger stimulation of immune cell chemotaxis than PEG-IFN-α2a. As HBsAg loss and HBV cccDNA eradication are important clinical goals, these results suggest a potential role for TRK-560 in the development of more effective treatment for chronic hepatitis B infection.

Ultradeep sequencing study of chronic hepatitis C virus genotype 1 infection in patients treated with daclatasvir, peginterferon, and ribavirin.

Direct-acting antivirals (DAAs) are either part of the current standard of care or are in advanced clinical development for the treatment of patients chronically infected with hepatitis C virus (HCV) genotype 1, but concern exists with respect to the patients who fail these regimens with emergent drug-resistant variants. In the present study, ultradeep sequencing was performed to analyze resistance to daclatasvir (DCV), which is a highly selective nonstructural protein 5A (NS5A) inhibitor. Eight patients with HCV genotype 1b, who were either treatment naive or prior nonresponders to pegylated interferon plus ribavirin (Rebetol; Schering-Plough) (PEG-IFN/RBV) therapy, were treated with DCV combined with PEG-IFN alpha-2b (Pegintron; Schering-Plough, Kenilworth, NJ) and RBV. To identify the cause of viral breakthrough, the preexistence and emergence of DCV-resistant variants at NS5A amino acids were analyzed by ultradeep sequencing. Sustained virological response (SVR) was achieved in 6 of 8 patients (75%), with viral breakthrough occurring in the other 2 patients (25%). DCV-resistant variant Y93H preexisted as a minor population at higher frequencies (0.1% to 0.5%) in patients who achieved SVR. In patients with viral breakthrough, DCV-resistant variant mixtures emerged at NS5A-31 over time that persisted posttreatment with Y93H. Although enrichment of DCV-resistant variants was detected, the preexistence of a minor population of the variant did not appear to be associated with virologic response in patients treated with DCV/PEG-IFN/RBV. Ultradeep sequencing results shed light on the complexity of DCV-resistant quasispecies emerging over time, suggesting that multiple resistance pathways are possible within a patient who does not rapidly respond to a DCV-containing regimen. (This study has been registered at ClinicalTrials.gov under registration no. NCT01016912.).

Achievement of sustained viral response after switching treatment from pegylated interferon α-2b to α-2a and ribavirin in patients with recurrence of hepatitis C virus genotype 1 infection after liver transplantation: a case report.

We report a case in which sustained viral response was achieved after switching treatment from pegylated interferon (PEG-IFN) α-2b to α-2a and ribavirin (RBV) in patients with recurrence of hepatitis C virus (HCV) infection after living donor liver transplantation. The patient was a 62-year-old man with liver cirrhosis due to HCV genotype 1b infection. The patient had 8 amino acid (aa) substitutions in the interferon sensitivity-determining region, and had substitutions for mutant and wild-type at aa70 and aa91, respectively, in the core region. The patient had minor genotype (GG) IL28B single nucleotide polymorphisms (rs8099917). He had initially received interferon α-2b and RBV for 2 years, and later developed hepatocellular carcinoma (HCC). After surgical resection of HCC, he subsequently received PEG-IFN α-2b and RBV for 1.5 years, without undetectable viremia during the treatment course. Due to recurrence of HCC, the patient received a living donor liver transplantation. Later on, hepatitis C relapsed. For the management of relapse, he received another course of PEG-IFN α-2b and RBV. However, breakthrough viremia occurred. PEG-IFN was thus switched from α-2b to α-2a and RBV for another 17 months. The patient eventually achieved a sustained viral response.

Interleukin-28B single nucleotide polymorphism of donors and recipients can predict viral response to pegylated interferon/ribavirin therapy in patients with recurrent hepatitis C after living donor liver transplantation.

BACKGROUND AND AIM: Interleukin-28B (IL28B) single nucleotide polymorphism (SNP) influences viral response (VR) to interferon (IFN) therapy in patients with hepatitis C. We studied the relationship between VR and the IL28B polymorphism (rs8099917) in patients on long-term pegylated IFN plus ribavirin (PEGIFN/RBV) therapy for recurrent hepatitis C after living-donor liver transplantation (LDLT). METHODS: Thirty-five patients with recurrent hepatitis C after LDLT were treated with PEGIFN/RBV. We evaluated the effect of IL28B SNP on the outcome in 20 patients infected with hepatitis C virus genotype 1 who completed IFN therapy. RESULTS: The sustained VR (SVR) rate was 54% (19/35) for all patients; 46% (13/28) for genotype 1. The SVR rate of donors' TT group (major genotype) was higher than that of donors' TG+GG group (minor genotype) (73% vs 20%), while that of recipients' TT group was similar to that of recipients' TG+GG group (64% vs 50%). With regard to the combined effect of donors' and recipients' IL28B SNP, the SVR rates of TT:TT (donors':recipients'), TT:TG+GG, TG+GG:any group were 81%, 50%, and 20%, respectively. The VR rate of TT:TT, TT:TG+GG and TG+GG:any group at 12 weeks were 28%, 0%, and 0%; those at 48weeks were 70%, 50%, 20%, and those at the end of treatment were 100%, 50%, 20%, respectively. The multivariate analysis identified IL28B of donors:recipients (TT:TT) as the only independent determinant of SVR (odds ratio 15.0, P=0.035). CONCLUSION: Measurement of donors' and recipients' IL28B SNP can predict the response to PEGIFN/RBV therapy, and the donors' IL28B SNP might be a more significant predictor than that of the recipients.

Serum miR-192-5p levels predict the efficacy of pegylated interferon therapy for chronic hepatitis B.

We examined the association between serum miRNA (-192-5p, -122-3p, -320a and -6126-5p) levels and the efficacy of pegylated interferon (Peg-IFN) monotherapy for chronic hepatitis B (CHB) patients. We enrolled 61 CHB patients treated with Peg-IFNα-2a weekly for 48 weeks, of whom 12 had a virological response (VR) and 49 did not VR (non-VR). A VR was defined as HBV DNA < 2,000 IU/ml, hepatitis B e antigen (HBeAg)-negative, and nucleos(t)ide analogue free at 48 weeks after the end of treatment. The non-VR group showed a significantly higher HBeAg-positivity rate, ALT, HBV DNA, and serum miR-192-5p levels at baseline (P = 0.024, P = 0.020, P = 0.007, P = 0.021, respectively). Serum miR-192-5p levels at 24-weeks after the start of treatment were also significantly higher in the non-VR than the VR group (P = 0.011). Multivariate logistic regression analysis for predicting VR showed that miR-192-5p level at baseline was an independent factor (Odds 4.5, P = 0.041). Serum miR-192-5p levels were significantly correlated with the levels of HBV DNA, hepatitis B core-related antigen, and hepatitis B surface antigen (r = 0.484, 0.384 and 0.759, respectively). The serum miR-192-5p level was useful as a biomarker for the therapeutic efficacy of Peg-IFN in CHB treatment.

IL28 variation affects expression of interferon stimulated genes and peg-interferon and ribavirin therapy.

BACKGROUND & AIMS: Common genetic variation within the IL28 locus has been found to influence the effect of peg-interferon and ribavirin combination therapy against chronic hepatitis C virus (HCV) infection. Expression of IL28 in peripheral blood cells has been reported to be higher in patients with IL28 SNP genotypes associated with favorable response. METHODS: We analyzed 52 liver and 114 blood samples obtained from patients with HCV genotype 1b. We used reverse transcription-real time polymerase chain reaction to analyze expression levels of IL28 and several interferon stimulated genes (ISGs), including MxA, double stranded RNA dependent protein kinase (PKR), 2'-5' oligo-nucleotide synthetase (OAS1), ISG15, and SOCS1. RESULTS: Interestingly, expression of IL28 was significantly lower in patients with the response-favorable rs8099917 TT genotype compared to those with TG or GG genotypes (p<0.005). In hepatic cells, expression of MxA, PKR, OAS1, and ISG15 were also significantly lower in rs8099917 TT patients (p<0.001, p=0.005, p=0.001, p<0.001, respectively), whereas in peripheral blood mononuclear cells ISG expression levels did not differ significantly. Among patients treated with peg-interferon plus ribavirin therapy, liver mRNA levels of IL28, MxA, PKR, OAS1, and ISG15 were significantly or marginally lower in responders who became negative for HCV RNA (p=0.001, 0.004, 0.014, 0.051, and 0.015, respectively). CONCLUSIONS: Expression levels of ISGs are differentially regulated in the liver and peripheral blood. The mechanism underlying the expression levels of IL28 and ISGs and the correlation with the effect of the therapy should be further investigated.

Prediction of response to peginterferon-alfa-2b plus ribavirin therapy in Japanese patients infected with hepatitis C virus genotype 1b.

Variation at the IL-28B locus was recently reported to be a significant predictive factor of viral response to pegylated-interferon plus ribavirin combination therapy against chronic hepatitis C. Predictive factors for the effect of therapy, including IL-28B polymorphism rs8099917 and viral and clinical factors were investigated. A total of 288 patients were enrolled who were chronically infected with hepatitis C virus (HCV) genotype 1b and treated with combination therapy. Among them, 87 patients completed 48 weeks of therapy without dose reduction or discontinuation. In multivariate regression analysis, the rs8099917 TT genotype was the only independent factor significantly associated with sustained viral response (P = 0.016, OR 61.5), whereas substitutions at amino acid 70 (aa 70) of the HCV core protein (P = 0.038, OR 5.9) and non-TT genotypes (P = 0.002, OR 17.2) were associated with nonvirological response. Both factors were also associated with viral dynamics during the initial stage of the therapy. Correlation analysis revealed that rs8099917 genotype was correlated with γ-glutamyl transpeptidase, hyaluronic acid, and HCV core aa 70. In conclusion, host (IL-28B polymorphism) and viral (aa 70) factors independently affect response to combination therapy.

Prolongation of interferon therapy for recurrent hepatitis C after living donor liver transplantation: analysis of predictive factors of sustained virological response, including amino acid sequence of the core and NS5A regions of hepatitis C virus.

OBJECTIVE: The aim of the present retrospective study was to evaluate the therapeutic efficacy and predictive factors of prolongation of treatment with peginterferon (PEGIFN) combined with ribavirin (RBV) for recurrent hepatitis C after living donor liver transplantation (LDLT). METHODS: Fifty-three patients underwent LDLT due to HCV-related end-stage liver disease. Sixteen patients were removed from the study as a result of early death (n=14), no recurrence of HCV (n=1) and refusal of antiviral therapy (n=1). Therapy is ongoing in another 10 patients. The remaining 27 patients were available to establish the efficacy of IFN therapy. HCV genotype was 1b in 24 patients. All patients with genotype 1b were treated with IFN therapy for at least 48 weeks after HCV RNA levels had become undetectable. Amino acid substitutions in the HCV core region and NS5A region were analyzed by direct sequencing before LDLT. RESULTS: The rate of sustained virological response (SVR) was 37.0% (10/27). SVR rate in patients with genotype 1 was 29.2% (7/24) and 100% (3/3) in patients with genotype 2. Most patients with genotype 1b whose HCV RNA reached undetectable levels achieved SVR (87.5%; 7/8). However, mutation of the HCV core region and number of ISDR mutations were not associated with SVR rate in LDLT in our study. CONCLUSIONS: Prolonged IFN therapy for more than 48 weeks after HCV RNA reached undetectable levels might prevent virological relapse of HCV.

Pilot study of tenofovir disoproxil fumarate and pegylated interferon-alpha 2a add-on therapy in Japanese patients with chronic hepatitis B.

BACKGROUND: A prospective pilot study of tenofovir disoproxil fumarate (TDF) and pegylated interferon alpha 2a (P-IFN) add-on therapy was conducted to evaluate its efficacy in reducing viral antigen levels in Japanese patients with chronic hepatitis B (UMIN 000020179). METHODS: Patients with chronic hepatitis B receiving maintenance TDF therapy and exhibiting hepatitis B surface antigen (HBsAg) level > 800 IU/ml were divided into two arms. P-IFN was added for 48 weeks in the add-on arm (n = 32), while TDF monotherapy was maintained in the control arm (n = 51). Both groups were followed for 96 weeks after baseline measurements. RESULTS: Almost all patients in the control arm displayed a slow and constant reduction in HBsAg during follow-up. In contrast, roughly half of the add-on arm exhibited a sharp decline in HBsAg during P-IFN administration, which disappeared after halting P-IFN. At 96 weeks after baseline, 41% (13/32) of patients in the add-on arm had shown a rapid decrease in HBsAg, versus 2% (1/51) in the control arm (p < 0.001). Add-on therapy and increased cytotoxic T-cell response were significant factors associated with a rapid decrease in HBsAg according to multivariate analysis. In addition, higher HB core-related antigen (HBcrAg) level at baseline (p = 0.001) and add-on therapy (p = 0.036) were significant factors associated with a rapid reduction in HBcrAg. CONCLUSIONS: TDF and P-IFN add-on therapy in Japanese patients with chronic hepatitis B facilitated rapid decreases in HBsAg and HBcrAg. Further studies are needed to improve early HBsAg clearance rate.

Reduction of hepatitis B surface antigen in sequential versus add-on pegylated interferon to nucleoside/nucleotide analogue therapy in HBe-antigen-negative chronic hepatitis B patients: a pilot study.

BACKGROUND: Although pegylated interferon (PEG-IFN) and nucleotide/nucleoside analogue (NA) combination therapy is considered to be optimal for accelerating serum hepatitis B surface antigen (HBsAg) reduction, the effect is limited, and the best approach to PEG-IFN treatment for chronic hepatitis B patients during long-term NA therapy has yet to be determined. METHODS: A total of 21 hepatitis B e antigen-negative chronic hepatitis B patients whose HBV DNA levels were suppressed to undetectable levels by NA therapy were administrated PEG-IFN-α2a for 48 weeks (sequential therapy: 10, add-on therapy: 11). Factors associated with HBsAg reduction by PEG-IFN therapy were analysed. RESULTS: During PEG-IFN treatment, HBsAg levels were reduced by 0.48 log IU/ml. More than 1 log IU/ml of HBsAg reduction was observed in eight patients (sequential therapy: six, add-on therapy: two), and one patient with sequential therapy achieved HBsAg loss. By univariate analysis, sequential therapy was marginally associated with more than 1 log IU/ml HBsAg reduction during PEG-IFN treatment (P=0.060). After PEG-IFN treatment, only five patients, including the patient with HBsAg loss, achieved more than 0.5 log IU/ml of HBsAg reduction by 1 year after PEG-IFN treatment. By univariate analysis, sequential therapy was significantly associated with HBsAg reduction after PEG-IFN treatment (P=0.012). In addition, alanine aminotransferase elevation during PEG-IFN therapy and lower serum interleukin-8 level at the end of PEG-IFN treatment were also significantly associated with HBsAg reduction by 1 year after PEG-IFN treatment (P=0.038, P=0.044, respectively). CONCLUSIONS: Sequential therapy may be superior to add-on therapy in reducing HBsAg levels during long-term NA therapy in chronic hepatitis B patients.

Involvement of Porphyromonas gingivalis in the progression of non-alcoholic fatty liver disease.

BACKGROUND AND AIMS: The risk factors in the progression of nonalcoholic fatty liver disease (NAFLD) have not been fully clarified. Porphyromonas gingivalis (P.g) has been considered to be a confounding risk factor for systemic diseases. We aimed to evaluate the effect of P.g infection on risk of progression to NASH. METHODS: (1) Serum IgG antibody titers against P.g fimbriae (fimA) in 200 biopsy-proven NAFLD patients were measured by ELISA and compared with histological findings. (2) C57BL/6J mice were fed a control diet (CD) or high-fat diet (HFD) with or without P.g-odontogenic infection and analyzed histologically. Mouse livers were analyzed using CE-TOFMS and LC-TOFMS. RESULTS: (1) A significant correlation between fibrosis progression and antibody titers against P.g possessing fimA type 4 was identified (P = 0.0081). Multivariate analysis identified older age and type 4 P.g-positivity as risk factors for advanced fibrosis. (2) Fibrosis and steatosis were more severe in HFD P.g(+) mice compared with HFD P.g(-) mice. In metabolome analysis, fatty acid metabolism was significantly disrupted with HFD in P.g-infected mouse livers. Monounsaturated/saturated fatty acid ratios were significantly higher in the HFD P.g(+) group than in the HFD P.g(-) group (P < 0.05). Moreover, expression levels of SCD1 and ELOVL6 were significantly reduced. CONCLUSIONS: These results suggest that P.g infection is an important risk factor for pathological progression in NAFLD. Increase in the monounsaturated/saturated fatty acid ratio may be an important change that facilitates progression of NAFLD.

Combinational use of hepatitis B viral antigens predicts responses to nucleos(t)ide analogue/peg-interferon sequential therapy.

BACKGROUND: This prospective cohort study searched for factors associated with a response to nucleos(t)ide analogue/peg-interferon (NUC/peg-IFN) sequential therapy. METHODS: A total of 95 patients with chronic hepatitis B being treated with NUCs were enrolled. Immediately following NUC cessation, peg-IFN was administered at 180 µg/dose weekly for 48 weeks. RESULTS: Twenty-six patients (27%) were judged to be responders at 48 weeks after the completion of peg-IFN. Analysis of baseline factors revealed that hepatitis B surface antigen (HBsAg) <3.1 log IU/ml and HB core-related antigen (HBcrAg) <3.9 log U/ml were significant indicators of a treatment response. The levels of the markers decreased in both responders and non-responders during peg-IFN therapy but continued falling in responders only after halting peg-IFN. Lower HBsAg (<2.0 log IU/ml) and HBcrAg (<3.8 log U/ml) levels at the time of response judgment were also significantly associated with a favorable response. While lower HBcrAg at baseline was the sole predictor of decreased HBcrAg levels at judgment, lower HBsAg, lower HBcrAg, and the use of adefovir dipivoxil at baseline predicted decreased HBsAg levels at the study endpoint. The use of adefovir dipivoxil was also associated with higher serum IFN-λ3, which might have contributed to the reduction in patient HBsAg levels. CONCLUSIONS: The combinational use of HBsAg and HBcrAg levels at baseline and their changes throughout sequential therapy may be useful for predicting a response to NUC/peg-IFN sequential therapy.

A case of chronic inflammatory demyelinating polyradiculoneuropathy after treatment with pegylated interferon α-2a in a patient with chronic hepatitis B virus infection.

We report the case of a 42-year-old man with chronic hepatitis B virus infection who developed weakness and paresthesia in the extremities 2 months after administration of pegylated interferon (Peg-IFN)α-2a. Nerve conduction studies conducted 6 months after onset showed abnormal temporal dispersions in both tibial nerves. We diagnosed chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) resulting from treatment with Peg-IFNα-2a. Neurological symptoms were prolonged despite suspension of the treatment. Subsequent treatment with intravenous immunoglobulin improved both clinical symptoms and temporal dispersion. IFNα-induced CIDP is rare, but can reportedly progress even after interruption of IFN-α without immunotherapy. Patients presenting with polyneuropathy after initiation of IFN-α thus require close attention.

Predictive value of the IFNL4 polymorphism on outcome of telaprevir, peginterferon, and ribavirin therapy for older patients with genotype 1b chronic hepatitis C.

BACKGROUND: Older patients with chronic hepatitis C have a lower virological response to interferon (IFN) treatment compared to younger patients. The efficacy of telaprevir (TVR) and PEG-IFN plus ribavirin combination therapy and the predictive value of recently identified IFN lambda (IFNL) 4 polymorphisms on the outcome of therapy for older patients have not been addressed. METHODS: We assessed predictive factors for sustained virological response (SVR) to triple therapy in 226 younger (≤65 years) and 87 older (>65 years) Japanese patients with chronic genotype 1 hepatitis C. IFNL4 polymorphism ss469415590 was analyzed by Invader assay. RESULTS: The SVR rate for older patients was slightly lower than for younger patients (69 vs. 82%, P = 0.043). In the older group, the SVR rate for patients with the IFNL4 TT/TT genotype was significantly higher than patients with TT/ΔG or ΔG/ΔG genotypes (81.8 and 42.9%, P = 0.003). In multivariate regression analysis, rapid virological response (OR 36.601, P = 0.002) and IFNL4 TT/TT genotype (OR 19.502, P = 0.009) were identified as significant independent predictors for SVR in older patients. Treatment-related decreases in hemoglobin and increases in serum creatinine were higher in older patients than younger patients. Reduction of initial TVR dose to 1,500 mg per day alleviated these adverse events without compromising SVR rate in older patients. CONCLUSIONS: Analysis of IFNL4 polymorphisms is a valuable predictor in older patients receiving TVR triple therapy. 1,500 mg per day is a suitable initial TVR dose for older Japanese patients.

IL28B polymorphism is associated with fatty change in the liver of chronic hepatitis C patients.

BACKGROUND: Several single nucleotide polymorphisms (SNPs) within the interleukin 28B (IL28B) locus are associated with sustained viral response in chronic hepatitis C (HCV) patients who were treated with pegylated interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. Recently, an association between γ-GTP level and IL28B genotype was identified. In this study, the relationship between IL28B genotype and liver steatosis was analyzed. METHODS: One hundred fifty-three patients who underwent liver biopsy before PEG-IFN plus RBV combination therapy were enrolled. The level of liver steatosis was measured using a BIOREVO BZ-9000 microscope, and the proportion of fatty change and clear cell change were calculated using Dynamic cell count BZ-H1C software. IL28B SNP genotype (rs8099917) was determined using the Invader Assay. RESULTS: Vesicular change was significantly associated with body mass index (BMI), HCV RNA titer, serum aspartate aminotransferase, γ-GTP, IL28B genotype and liver fibrosis level (P < 0.05). Clear cell change was significantly associated with serum aspartate aminotransferase, γ-GTP and IL28B genotype by univariate logistic regression analysis (P < 0.05). Under multiple logistic regression, IL28B genotype (OR(adj) = 8.158; 95% CI 2.412-27.589), liver fibrosis (OR(adj) = 2.541; 95% CI 1.040-6.207) and BMI (OR(adj) = 1.147; 95% CI 1.011-1.301) were significant independent factors for vesicular change and IL28B genotype (OR(adj) = 3.000; 95% CI 1.282-7.019) for clear cell change. CONCLUSION: In this study, a new quantitative method to objectively evaluate hepatic steatosis was described. IL28B genotypes were significantly associated with both vesicular and clear cell changes of livers in chronic hepatitis C patients.

Amino acid substitutions in core and NS5A regions of the HCV genome can predict virological decrease with pegylated interferon plus ribavirin therapy.

BACKGROUND: The current standard therapy for chronic hepatitis C is pegylated interferon (PEG-IFN) plus ribavirin (RBV) combination therapy. Recently, it has been reported that amino acid (aa) substitutions in the core region, as well as the IFN-sensitivity-determining region (ISDR), were predictive of non-virological response (NVR), sustained virological response (SVR) and early virological response. Despite the importance of these two predictive factors for combination therapy, their interaction is poorly understood. METHODS: A total of 117 patients who were treated with PEG-IFN-α2b plus RBV combination therapy were selected for participation in this study. We determined the aa sequences in the core region and ISDR by direct sequencing and analysed them along with clinical data to identify predictive factors for therapeutic response. RESULTS: The aa sequences in the core region and γ-glutamyl transpeptidase (GTP) levels were associated with SVR and NVR, but aa sequences in the ISDR were not. However, substitutions at both aa 70 and aa 91 in the core region without substitutions in the ISDR and higher levels of γ-GTP were independent predictive factors for NVR. Wild-type aa 70 and aa 91 in the core region, higher platelet counts and lower levels of γ-GTP were independent predictive factors for SVR. CONCLUSIONS: These results indicate that analyses of aa substitutions in both the core region and the ISDR are useful for predicting the effectiveness of combination therapy, and could help to avoid therapy exposure for patients who have a low probability of SVR.