Japanese Chronic Hepatitis Research Articles

Validation of hepatocellular carcinoma risk scores in Japanese chronic hepatitis B cohort receiving nucleot(s)ide analog.

The prediction of hepatocellular carcinoma (HCC) development during nucleotide/nucleoside analog (NA) therapy is clinically important in patients with chronic hepatitis B. Although several useful models for HCC prediction have been previously reported, their usefulness in the Japanese population is unclear. Therefore, this study examines the applicability of these models in Japanese patients. Four hundred forty-three patients with no history of HCC who were treated with entecavir, tenofovir alafenamide, or tenofovir disoproxil fumarate were enrolled. PAGE-B, modified-PAGE-B, and REACH-B scores were calculated, and subsequent HCC development was investigated. The mean follow-up duration was 5.1years, and a total of 33 patients (7.4%) developed HCC during the follow-up period. Multivariate analysis revealed that old age (hazard ratio [HR] 1.05, 95% confidence interval [CI] 1.01-1.09, P=0.011), male gender (HR 2.62, 95% CI 1.06-6.49, P=0.037), and low platelet count (HR 0.83, 95% CI 0.77-0.91, P<0.001) were independent predictors of HCC development. These factors are the same as the factors identified in the PAGE-B model. Time-dependent area under the receiver operating characteristic (AUROC) curve revealed that the AUROCs for 3 and 7years of PAGE-B (AUROC: 0.786 and 0.744 at 3 and 7years, respectively) were continuously higher than those of REACH-B (0.658 and 0.543) and modified PAGE-B AUROC (0.772 and 0.731). PAGE-B, which can easily identify high-risk cases, can be useful for predicting HCC development in Japanese patients treated with NA therapy.

Albumin-Bilirubin Score Differentiates Liver Fibrosis Stage and Hepatocellular Carcinoma Incidence in Chronic Hepatitis B Virus Infection: A Retrospective Cohort Study.

.The albumin–bilirubin (ALBI) score was originally established to stratify prognosis in patients with cirrhosis. The diagnostic accuracy of ALBI score in liver fibrosis staging in patients with chronic hepatitis B remains to be investigated. The present retrospective study, therefore, aimed to evaluate the ability of this score to stage liver fibrosis in these patients. Briefly, consecutive patients with hepatitis B virus (HBV) infection who underwent liver biopsy examinations in Kagawa University Hospital were enrolled. Liver fibrosis stage was assessed using a modified Meta-Analysis of Histological Data in Viral Hepatitis score. Albumin–bilirubin scores were calculated according to the following equation: (log10 total bilirubin [T-Bil] × 0.66) + (albumin [Alb] × −0.085). A total of 91 patients were enrolled in this study. Albumin–bilirubin score was able to differentiate stage 4 from stage 3 fibrosis (P < 0.05). When an ALBI score of −2.190 was adopted as the cutoff value for differentiating stage 4 from stages 1–3, the sensitivity, specificity, and positive likelihood ratio were 85.7%, 74.0%, and 3.300, respectively. Kaplan–Meier analysis showed that baseline ALBI scores < −2.190 correlated with better hepatocellular carcinoma (HCC)–free survival (P < 0.05). In conclusion, ALBI score can be used for liver fibrosis staging in Japanese chronic hepatitis B patients and can help distinguish cirrhotic from non-cirrhotic status. Furthermore, ALBI score was useful as a prognosis biomarker in our patients, with smaller ALBI scores predicting better HCC-free survival. Because calculating ALBI score is easy using serum T-Bil and Alb alone, ALBI score will help clinicians with decision-making in management of HBV-infected patients.

THU-350 - Efficacy and safety of direct-acting antivirals for 1,961 Japanese chronic hepatitis C patients – Real Word Data from a multicenter cohort

THU-350 - Efficacy and safety of direct-acting antivirals for 1,961 Japanese chronic hepatitis C patients – Real Word Data from a multicenter cohort

Efficacy and safety of telaprevir with natural human interferon-β and ribavirin in Japanese chronic hepatitis C patients with depression.

To assess the efficacy and safety of telaprevir (TVR) when used in combination with natural human interferon-β (IFN-β) and ribavirin (RBV) for genotype 1 patients with depression compared to IFN-β/RBV therapy in Japan. We also examined the efficacy of the TVR/IFN-β/RBV therapy in treatment failure genotype 2 patients with depression. For the genotype 1 patients, 30 patients received TVR (750mg every 8h) for 12weeks combined with IFN-β and RBV for 24weeks (Group A), and 30 received IFN-β and RBV for 48weeks (Group B). For the genotype 2 patients, 14 patients were dosed only with the TVR-based regimen. The sustained virologic response (SVR) rates for Group A and Group B were 63.3% and 20.0%, respectively (P = 0.001, likelihood ratio test). The SVR rate for genotype 2 patients previously treated with pegylated IFN and/or RBV was 71.4%. No patient dropped out due to exacerbation of depression. The trend of platelet counts after the drugs were given was similar in the TVR/IFN-β/RBV therapy group and the IFN-β/RBV therapy group. Common resistance-associated variants of TVR were identified in 4 of the 13 patients who did not achieve SVR. This study showed that an addition of TVR to IFN-β/RBV therapy raised SVR in previously treated and untreated genotype 1 patients and previously treated genotype 2 patients with chronic hepatitis C and depression.

Randomized prospective study showing the non-inferiority of tenofovir to entecavir in treatment-naïve chronic hepatitis B patients.

The study aimed to evaluate the efficacy and safety of tenofovir disoproxil fumarate (TDF) and entecavir hydrate (ETV) in nucleos(t)ide analog (NA)-naïve Japanese chronic hepatitis B (CHB) patients. This multicenter, randomized, double-blinded study assessing the efficacy and safety of TDF 300mg and ETV 0.5mg in NA-naïve CHB subjects was carried out from November 2011 to November 2014, and funded by GlaxoSmithKline. The subjects were assigned to the TDF arm or ETV arm in a 2:1 ratio. The primary efficacy endpoint was the non-inferiority of TDF to ETV at week 24. A total of 166 subjects (TDF arm, 110; ETV arm, 56) were enrolled. The change (mean ± SE) in serum hepatitis B virus (HBV)-DNA levels from baseline to week 24 was -4.63 ± 0.044 and -4.50 ± 0.063 log10 copies/mL in the TDF and ETV arms, respectively, indicating the non-inferiority of TDF to ETV (P <0.0001). The proportion of subjects with undetectable HBV-DNA increased from 54 to 77% and 39 to 66% in the TDF and ETV arms with continuation of the treatment from week 24 to 48, respectively. Reduction in hepatitis B surface antigen level was greater in subjects with hepatitis B envelope antigen (+) and high alanine aminotransferase levels (≥80IU/L). Prevalence of drug-related adverse events at week 48 was 20% and 18% in the TDF and ETV arms, respectively. The study is the first to report that TDF has non-inferiority to ETV in treatment effectiveness (lowering of serum HBV-DNA level) at week 24. ClinicalTrials.gov trial registration nos. NCT01480284 and GSK LOC115409.

Tu1680 Glyco-Isomer of Serum MAC-2-Binding Protein Is Associated With the Risk of Developing Hepatocellular Carcinoma After Achieving Sustained Viral Response in Japanese Chronic Hepatitis C Patients

Tu1680 Glyco-Isomer of Serum MAC-2-Binding Protein Is Associated With the Risk of Developing Hepatocellular Carcinoma After Achieving Sustained Viral Response in Japanese Chronic Hepatitis C Patients

Liver stiffness-spleen size-to-platelet ratio risk score identifies esophageal varices in Japanese patients with chronic hepatitis C.

Non-invasive methods are needed to identify esophageal varices (EV) in patients with chronic liver disease. To this end, we evaluated liver stiffness (LS)-spleen diameter-to-platelet ratio risk score (LSPS) in predicting EV among Japanese chronic hepatitis C patients. A total of 99 patients with chronic hepatitis C who had undergone endoscopy, LS measurement and ultrasonography between 2013 and 2014 were enrolled. Clinical data were compared with those for other non-invasive markers (platelet count, aspartate aminotransferase-to-platelet ratio, FIB-4 index and platelet-to-spleen ratio), spleen size, LS and controlled attenuation parameter. Diagnostic applicability was assessed by the area under the receiver-operator curve (AUC) and predictive values along with multivariate logistic regression. LSPS was significantly correlated to the grade of EV (ρ = 0.617, P < 0.001) and was superior to the other non-invasive indices for determination of EV. LSPS was independently associated with EV by multivariate logistic regression analysis (odds ratio, 3.079; 95% confidence interval [CI], 2.137-4.438; P < 0.001). The cut-off value of LSPS for EV was 0.7, for which the AUC, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 0.928 (95% CI, 0.876-0.980), 86.3%, 89.6%, 70.4%, 95.8% and 88.9%, respectively. LSPS may also identify EV in patients with chronic hepatitis C in Japan. The clinical values of LSPS for EV risk merit further validation in larger prospective studies.

Influencing factors on serum 25-hydroxyvitamin D3 levels in Japanese chronic hepatitis C patients.

BackgroundSerum 25-hydroxyvitamin D3 levels are generally lower in chronic hepatitis C patients than in healthy individuals. The purpose of this study is to clarify the factors which affect serum 25-hydroxyvitamin D3 levels using data obtained from Japanese chronic hepatitis C patients.MethodsThe subjects were 619 chronic hepatitis C patients. Serum 25-hydroxyvitamin D3 levels were measured by using double-antibody radioimmunoassay between April 2009 and August 2014. Serum 25-hydroxyvitamin D3 levels of 20 ng/mL or less were classified as vitamin D deficiency, and those with serum 25-hydroxyvitamin D3 levels of 30 ng/mL or more as vitamin D sufficiency. The relationship between patient-related factors and serum 25-hydroxyvitamin D3 levels was analyzed.ResultsThe cohort consisted of 305 females and 314 males, aged between 18 and 89 years (median, 63 years). The median serum 25-hydroxyvitamin D3 level was 21 ng/mL (range, 6–61 ng/mL). On the other hand, the median serum 25-hydroxyvitamin D3 level in the healthy subjects was 25 ng/mL (range, 7–52), being significantly higher than that those in 80 chronic hepatitis C patients matched for age, gender, and season (p = 1.16 × 10−8). In multivariate analysis, independent contributors to serum 25-hydroxyvitamin D3 deficiency were as follows: female gender (p = 2.03 × 10−4, odds ratio = 2.290, 95 % confidence interval = 1.479–3.545), older age (p = 4.30 × 10−4, odds ratio = 1.038, 95 % confidence interval = 1.017–1.060), cold season (p = 0.015, odds ratio = 1.586, 95 % confidence interval = 1.095–2.297), and low hemoglobin level (p = 0.037, odds ratio = 1.165, 95 % confidence interval = 1.009–1.345). By contrast, independent contributors to serum 25-hydroxyvitamin D3 sufficiency were male gender (p = 0.001, odds ratio = 3.400, 95 % confidence interval = 1.635–7.069), warm season (p = 0.014, odds ratio = 1.765, 95 % confidence interval = 1.117–2.789) and serum albumin (p = 0.016, OR = 2.247, 95 % CI = 1.163–4.342).ConclusionsSerum 25-hydroxyvitamin D3 levels in chronic hepatitis C Japanese patients were influenced by gender, age, hemoglobin level, albumin and the season of measurement.

Hepatic flares promote rapid decline of serum hepatitis B surface antigen (HBsAg) in patients with HBsAg seroclearance: A long‐term follow‐up study

Serum hepatitis B surface antigen (HBsAg) seroclearance is one of the ultimate goals of management of chronic hepatitis B. We investigated the kinetics of serum HBsAg before HBsAg seroclearance in patients with chronic hepatitis B. We retrospectively analyzed 392 Japanese chronic hepatitis B patients who had been followed for 5 years or more between 1980 and 2000. Serum HBsAg levels were measured annually using chemiluminescent enzyme immunoassay. During a median follow up of 14 years, 50 patients demonstrated HBsAg seroclearance (annual incidence rate, 0.91%). Multivariate analysis with baseline characteristics revealed that HBsAg of less than 3.3 log IU/mL (hazard ratio [HR], 2.22; P = 0.008) and treatment with nucleoside/nucleotide analog (HR, 0.12; P = 0.001) were independent predictive factors for seroclearance. The median HBsAg levels at 20, 10, 5, 3 and 1 year prior to seroclearance were 3.89, 2.84, 1.84, 0.78 and -1.10 log IU/mL, respectively. The rapid decline group, comprising patients who achieved HBsAg seroclearance within 5 years after confirmed HBsAg levels of 2 log IU/mL, demonstrated: (i) high alanine aminotransferase (ALT) levels; and (ii) a low frequency of liver cirrhosis progression. A significant reduction in annual HBsAg levels was found in years marked by at least one ALT flare (ALT ≥200 IU/L) (flare [+], n = 62) than in those without (flare [-], n = 323) (0.29 vs 0.17 log IU/mL/year, P = 0.003). Hepatic flares promoted rapid declines and greater annual reductions of HBsAg levels in patients with HBsAg seroclearance.

PNPLA3 I148M associations with liver carcinogenesis in Japanese chronic hepatitis C patients.

AimTo investigate associations between patatin-like phospholipase domain-containing 3 (PNPLA3) genotypes and fibrosis and hepatocarcinogenesis in Japanese chronic hepatitis C (CHC) patients.MethodsTwo hundred and thirty-one patients with CHC were examined for PNPLA3 genotypes, liver stiffness measurements (LSM), and hepatocellular carcinoma (HCC) from May 2010 to October 2012 at Fujita Health University Hospital. The rs738409 single nucleotide polymorphism (SNP) encoding for a functional PNPLA3 I148M protein variant was genotyped using a TaqMan predesigned SNP genotyping assay. LSM was determined as the velocity of a shear wave (Vs) with an acoustic radiation force impulse. Vs cut-off values for cirrhosis were set at 1.55 m/s. We excluded CHC patients with a sustained virological response or relapse after interferon treatment.ResultsPNPLA3 genotypes were CC, CG, and GG for 118, 72, and 41 patients, respectively. Multivariable logistic regression analysis selected older age (OR = 1.06; 95% CI: 1.03–1.09; p < 0.0001), higher body mass index (BMI) (OR= 1.12; 95% CI: 1.03–1.22; p = 0.0082), and PNPLA3 genotype GG (OR = 2.07; 95% CI: 0.97–4.42; p = 0.0599) as the factors independently associated with cirrhosis. When 137 patients without past history of interferon treatment were separately assessed, multivariable logistic regression analysis selected older age (OR = 1.05; 95% CI: 1.02–1.09; p = 0.0034), and PNPLA3 genotype GG (OR = 3.35; 95% CI: 1.13–9.91; p = 0.0291) as the factors independently associated with cirrhosis. Multivariable logistic regression analysis selected older age (OR = 1.12; 95% CI: 1.07–1.17; p < 0.0001), PNPLA3 genotype GG (OR = 2.62; 95% CI: 1.15–5.96; p = 0.0218), and male gender (OR = 1.83; 95% CI: 0.90–3.71); p = 0.0936) as the factors independently associated with HCC.ConclusionPNPLA3 genotype I148M is one of risk factors for developing HCC in Japanese CHC patients, and is one of risk factors for progress to cirrhosis in the patients without past history of interferon treatment.

IFNL4/IL-28B haplotype structure and its impact on susceptibility to hepatitis C virus and treatment response in the Japanese population

A new type III interferon, IFN lambda 4 (IFNL4), and its single-nucleotide polymorphism (SNP) ss469415590 causing a frame shift have been recently reported strongly to affect antiviral therapy for chronic hepatitis C virus (HCV) infection in African and Caucasian populations compared to previously reported IL-28B SNPs rs12979860 and rs8099917. To compare the predictability for treatment outcome among those polymorphisms, we estimated haplotype structure of IFNL4/IL-28B consisting of the three SNPs in 4630 Japanese chronic hepatitis C patients and 1122 healthy controls and then compared their impact on response to pegylated-IFN (PEG-IFN) plus ribavirin (RBV) combined therapy in 903 HCV-1b-infected patients. A total of five haplotypes were identified, although two major haplotypes accounted for >99 % of the variation. The SNPs were tightly linked but not in absolute linkage disequilibrium. We could not find any difference in the predictive impact of any of these three SNPs with regard to susceptibility to HCV and treatment response. However, patients with favourable rs8099917 TT, linked to unfavourable genotypes of ss469415590 and rs12979860, showed poor initial viral response compared with those with all favourable genotypes (P = 0.0022). These findings suggest that, in part, ss469415590 and rs12979860 may have better predictive impact on response to PEG-IFN plus RBV therapy in the Japanese population, especially in patients with any of the minor haplotypes consisting of these SNPs.

Genetic polymorphism inIFNL4and response to pegylated interferon-α and ribavirin in Japanese chronic hepatitis C patients

A genetic polymorphism of the newly discovered interferon-λ 4 (IFNL4) gene was associated with hepatitis C virus (HCV) clearance in individuals of African ancestry. To assess whether a dinucleotide variant of IFNL4 (ss469415590) also affected treatment outcome of antiviral therapy in Japan, we genotyped 213 patients with chronic genotype 1 HCV infection and 176 healthy subjects. The ΔG allele was associated with treatment failure [odds ratio (OR) 4.73, P = 0.019], as was the IFL3 rs8099917 single nucleotide polymorphism (SNP) (OR 5.06, P = 0.068). The correlation between ss469415590 and rs8099917 was high (r(2) = 0.92, D' = 0.98). Multivariate analysis revealed that the rs8099917 SNP was independently associated with treatment failure (OR 5.28, P = 0.009). Therefore, ss469415590 may be another predictive marker of antiviral therapy outcome in the Japanese population.

Baseline factors and very early viral response (week 1) for predicting sustained virological response in telaprevir-based triple combination therapy for Japanese genotype 1b chronic hepatitis C patients: a multicenter study

Genetic polymorphisms near Interleukin 28B (IL28B) (rs8099917) and a rapid virological response (RVR) have been reported as predictors for a sustained virological response (SVR) to telaprevir (TVR)-based triple combination therapy. However, the association between SVR and viral kinetics earlier than week 4 after initiation of therapy remains unclear. Thus, we evaluated the SVR prediction ability of baseline factors and reduced hepatitis C virus (HCV) RNA levels at week 1 after the initiation of TVR-based therapy in Japanese genotype-1b chronic hepatitis C (CHC) patients. A total of 156 Japanese CHC patients received a 24-week regimen of TVR-based therapy. Baseline factors and reduction in HCV RNA levels at weeks 1 and 4 after the initiation of therapy were analyzed for SVR prediction. Multiple logistic regression analysis for SVR in TVR-based therapy identified the IL28B TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1, RVR, and treatment-naïve/relapse. Whereas the SVR rate was higher than 90 % regardless of the reduction in HCV RNA levels at week 1 in patients with the TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1 was the strongest predictor of SVR in patients with the non-TT genotype, as determined by multiple logistic regression analysis (P = 0.0043). The IL28B TT genotype is the most important baseline factor for predicting SVR, and a ≥ 4.7 log10 IU/mL reduction in HCV RNA at week 1 is a useful very early on-treatment predictor of SVR, especially in the non-TT genotype.

Efficacy of pegylated interferon alpha-2b and ribavirin treatment on the risk of hepatocellular carcinoma in patients with chronic hepatitis C: A prospective, multicenter study

The effects of pegylated interferon (PegIFN) α and ribavirin (RBV) treatment of chronic hepatitis C on the incidence of hepatocellular carcinoma (HCC) have not been well established. This study investigated the impact of treatment outcome on the development of HCC by chronic hepatitis C patients treated with PegIFNα2b and RBV. This large-scale, prospective, multicenter study consisted of 1013 Japanese chronic hepatitis C patients with no history of HCC (non-cirrhosis, n=863 and cirrhosis, n=150). All patients were treated with PegIFNα2b and RBV and the follow-up period started at the end of the antiviral treatment (median observation period of 3.6 years). The cumulative incidence rate of HCC was estimated using the Kaplan-Meier method, according to treatment outcome. Forty-seven patients (4.6%) developed HCC during the observation period. In the non-cirrhosis group, the 5-year cumulative incidence rates of HCC for the sustained virological response (SVR) (1.7%) and transient virological response (3.2%) (TVR: defined as relapse or breakthrough) groups were significantly lower than those of the non-virological response (NVR) group (7.6%) (p=0.003 and p=0.03, respectively). A significantly low rate of incidence of HCC by TVR patients in comparison with NVR patients was found for patients aged 60 years and over, but not for those under 60 years of age. In the cirrhosis group, the 5-year cumulative incidence rates of HCC for the SVR (18.9%) and TVR groups (20.8%) were also significantly lower than those of the NVR group (39.4%) (p=0.03 and p=0.04, respectively). SVR and complete viral suppression during treatment with relapse (TVR) were associated with a lower risk of HCC development when compared with NVR.

Factors responsible for the discrepancy between IL28B polymorphism prediction and the viral response to peginterferon plus ribavirin therapy in Japanese chronic hepatitis C patients

IL28B polymorphisms serve to predict response to pegylated interferon plus ribavirin therapy (PEG IFN/RBV) in Japanese patients with chronic hepatitis C (CHC) very reliably. However, the prediction by the IL28B polymorphism contradicted the virological response to PEG IFN/RBV in some patients. Here, we aimed to investigate the factors responsible for the discrepancy between the IL28B polymorphism prediction and virological responses. CHC patients with genotype 1b and high viral load were enrolled in this study. In a case-control study, clinical and virological factors were analyzed for 130 patients with rs8099917 TT genotype and 96 patients with rs8099917 TG or GG genotype who were matched according to sex, age, hemoglobin level and platelet count. Higher low-density lipoprotein (LDL) cholesterol, lower γ-glutamyltransferase and the percentage of wild-type phenotype at amino acids 70 and 91 were significantly associated with the rs8099917 TT genotype. Multivariate analysis showed that rs8099917 TG or GG genotype, older age and lower LDL cholesterol were independently associated with the non-virological responder (NVR) phenotype. In patients with rs8099917 TT genotype (predicted as virological responder [VR]), multivariate analysis showed that older age was independently associated with NVR. In patients with rs8099917 TG or GG genotype (predicted as NVR), multivariate analysis showed that younger age was independently associated with VR. Patient age gave rise to the discrepancy between the prediction by IL28B polymorphism and the virological responses, suggesting that patients should be treated at a younger age.

Pegylated interferon α‐2b plus ribavirin for Japanese chronic hepatitis C patients with normal alanine aminotransferase

To investigate the efficacy and safety of a pegylated interferon (PEG-IFN) α-2b plus ribavirin (RBV) combination treatment for patients with chronic hepatitis C virus (HCV) infection who have persistently normal alanine aminotransferase (NALT). This multicenter study included 989 patients with HCV genotype 1 (114 with NALT and 875 with elevated ALT) who received weight-based doses of PEG-IFN α-2b plus RBV for 48 weeks. We compared the sustained viral response (SVR) rates of patients with NALT and elevated ALT who received at least 80% or more of the target dosage of PEG-IFN α-2b and 60% or more of the target RBV (minimum acceptable dosage). No significant difference was found in the overall SVR rate between the NALT (42.1%) and elevated ALT groups (37.3%). No significant difference in the SVR rates was found between NALT (63.3%) and elevated ALT group (61.6%) patients who received minimum acceptable dosage. Multivariate analysis showed that age (<65 years old) and total cholesterol (≧220 mg/dL) were significantly independent positive factors associated with an SVR in the NALT group. Twenty-four weeks after treatment, an ALT increase above the normal range was observed for 34.0% (18 of 53) of the non-responsive group of NALT patients. The efficacy and safety of PEG-IFN α-2b plus RBV combination therapy for patients with chronic HCV infection are similar for patients with NALT and those with elevated ALT levels. These results indicate that patients with NALT should be considered for treatment with PEG-IFN α-2b plus RBV.

Pooled model-based approach to compare the pharmacokinetics of entecavir between Japanese and non-Japanese chronic hepatitis B patients

This study evaluated the population pharmacokinetics (PK) of entecavir in Japanese patients with chronic hepatitis B infection enrolled in 2 Japanese phase IIb clinical trials and compared them to non-Japanese patients enrolled in global phase II trials. The objectives were to identify significant and clinically meaningful covariate effects on entecavir population pharmacokinetic parameters and assess whether differences exist between Japanese and non-Japanese patients. A total of 843 observations were obtained from 142 patients who received once daily administration of entecavir at 0.1, 0.5, and 1.0 mg doses in the 2 Japanese studies. Consistent with findings in non-Japanese patients, creatinine clearance estimated with ideal body weight (ICrCL) was found to be statistically significant for clearance in a 2-compartment model. Also, the entecavir dose was identified as a covariate on intercompartmental clearance. Age, gender, and hepatic function were not identified as covariate for clearance. The estimated population average of oral clearance in a typical patient with a reference ICrCL value of 100 mL/min was 26.4 L/h (interindividual variability: 19.4%). This model-based analysis indicates that the PK of entecavir are similar in Japanese and non-Japanese chronic hepatitis B patients.

The rs8099917 Polymorphism, When Determined by a Suitable Genotyping Method, Is a Better Predictor for Response to Pegylated Alpha Interferon/Ribavirin Therapy in Japanese Patients than Other Single Nucleotide Polymorphisms Associated with Interleukin-28B

We focused on determining the most accurate and convenient genotyping methods and most appropriate single nucleotide polymorphism (SNP) among four such polymorphisms associated with interleukin-28B (IL-28B) in order to design tailor-made therapy for patients with chronic hepatitis C virus (HCV) patients. First, five different methods (direct sequencing, high-resolution melting analysis [HRM], hybridization probe [HP], the InvaderPlus assay [Invader], and the TaqMan SNP genotyping assay [TaqMan]) were developed for genotyping four SNPs (rs11881222, rs8103142, rs8099917, and rs12979860) associated with IL-28B, and their accuracies were compared for 292 Japanese patients. Next, the four SNPs associated with IL-28B were genotyped by Invader for 416 additional Japanese patients, and the response to pegylated interferon/ribavirin (PEG-IFN/RBV) treatment was evaluated when the four SNPs were not in linkage disequilibrium (LD). HRM failed to genotype one of the four SNPs in five patients. In 2 of 287 patients, the results of genotyping rs8099917 by direct sequencing differed from the results of the other three methods. The HP, TaqMan, and Invader methods were accurate for determination of the SNPs associated with IL-28B. In 10 of the 708 (1.4%) patients, the four SNPs were not in LD. Eight of nine (88.9%) patients whose rs8099917 was homozygous for the major allele were virological responders, even though one or more of the other SNPs were heterozygous. The HP, TaqMan, and Invader methods were suitable to determine the SNPs associated with IL-28B. The rs8099917 polymorphism should be the best predictor for the response to the PEG-IFN/RBV treatment among Japanese chronic hepatitis C patients.

HCV Core Gene Polymorphisms Correlate with Liver Fibrosis but Not Sustained Virological Response in Patients with Genotype 1 Infection

Amino acid (aa) substitutions in genotype 1 HCV core region (HCV-CR) serve as a negative predictor of treatment responses in Japanese chronic hepatitis C (CHC) patients. Whether this phenomenon could be extrapolated to non-Japanese patients remains unclear. We evaluated the effect of aa substitutions in HCV-CR on clinicopathological features and treatment responses in Taiwanese patients. Clinical and serial virological data were collected from 147 consecutive Taiwanese HCV genotype 1 patients who received pegylated interferon plus ribavirin therapy. Quantification of HCV RNA and sequences of HCV-CR were determined by molecular methods. Of 147 patients, 90 (61.2%) attained rapid virological response (RVR) and 97 (66.0%) attained sustained virological response (SVR). Patients without aa substitutions in HCV-CR (coreWW) had a higher SVR than those with both aa70 and aa91 substitutions (coreMM; 70.5% versus 45.0%; P=0.039). Moreover, coreMM was associated with a higher γ-glutamyl transpeptidase level (P=0.026) as well as more severe liver fibrosis (P=0.027) than coreWW, and patients with aa70 substitution (coreMW) were associated with more severe liver steatosis and fibrosis than those without (P=0.020 and P=0.002, respectively). In multivariate analyses, lower pretreatment body mass index, milder liver fibrosis, 48 weeks of treatment and RVR, but not aa substitutions in HCV-CR, predicted a higher SVR rate. Although aa substitution in genotype 1 HCV-CR is associated with more severe liver fibrosis and might be a negative predictor of SVR in Taiwanese CHC patients with interferon-based therapy, RVR and other clinical factors outweigh its role in predicting SVR.

Long-term effects of lamivudine treatment in Japanese chronic hepatitis B patients

To analyze the association between the emergence of tyrosine-methionine-asparatate-asparatate (YMDD) mutants (reverse transcription; rtM204I/V) and deterioration of liver function during long-term lamivudine treatment of Japanese patients with chronic hepatitis B virus (HBV) infection. The data of 61 consecutive Japanese patients with chronic hepatitis B who underwent continuous lamivudine treatment for more than 24 mo and had a virological response were analyzed. Analysis of YMDD mutants was done by real-time polymerase chain reaction with LightCycler probe hybridization assay for up to 90 mo (mean, 50.8 mo; range, 24-90 mo). A mixed mutant-type (YMDD + tyrosine-isoleucine-asparatate-asparatate: YIDD or tyrosine-valine-asparatate-asparatate: YVDD) or a mutant-type (YIDD or YVDD) were found in 57.4% of 61 patients at 1 year, 78.7% of 61 patients at 2 years, 79.6% of 49 patients at 3 years, 70.5% of 34 patients at 4 years, 68.4% of 19 patients at 5 years, 57.1% of 14 patients at 6 years, and 33.3% of 6 patients at 7 years. Of the 61 patients, 56 (92%) had mixed mutant- or a mutant-type. Only 5 (8%) had no mutants at each observation point. Virological breakthrough was found in 26 (46.4%) of 56 patients with YMDD mutants, 20 of whom had a hepatitis flare-up: the remaining 30 (53.6%) had neither a virological breakthrough nor a flare-up. All 20 patients who developed a hepatitis flare-up had a biochemical and virological response after adefovir was added to the lamivudine treatment. Our results suggest that it is possible to continue lamivudine treatment, even after the emergence of YMDD mutants, up to the time that the patients develop a hepatitis flare-up.