Predictive factors of early and sustained responses to peginterferon plus ribavirin combination therapy in Japanese patients infected with hepatitis C virus genotype 1b: amino acid substitutions in the core region and low-density lipoprotein cholesterol levels

Factors of response to pegylated interferon/ribavirin combination therapy and mechanism of viral clearance

OBJECTIVES

This study explores viral factors of the interferon (IFN) and ribavirin (RBV) resistance-determining region (IRRDR), the IFN sensitivity-determining region (ISDR) and the core protein, and host factor interleukin 28B associated with response to pegylated IFN (PEG-IFN) and RBV combination therapy, and the correlation of viral and host factors with IFN-λ1.

METHODS

A total of 58 patients underwent PEG-IFN/RBV combination therapy for 48 weeks. The pretreatment factors associated with rapid virological response (RVR) and sustained virological response (SVR) were analyzed. Pretreatment IFN-λ1 serum levels were compared with the viral and host factors.

RESULTS

Univariate analysis showed that IRRDR ≥6 and ISDR ≥2 were significant pretreatment predictors of RVR, and multivariate analysis identified IRRDR ≥6 and hemoglobin as significant predictors of SVR. Pretreatment IFN-λ1 was significantly higher in the SVR group than in the non-SVR group and also in the IRRDR ≥6 group than in the IRRDR ≤5 group.

CONCLUSIONS

IRRDR ≥6 was the only significant predictor of SVR and was correlated with IFN-λ1. High serum levels of IFN-λ1 may be conducive to effective PEG-IFN/RBV combination therapy because of the immunomodulatory system.

Telaprevir is effective given every 12 h at 750 mg with pegylated interferon-α2b and ribavirin to Japanese patients with HCV-1b IL28B rs8099917 TT

BACKGROUND

The aim of this study is to explore the efficacy, safety and pharmacokinetics of 750 mg telaprevir (TVR) given at 8 or 12 h intervals during triple therapy with pegylated interferon-α2b (PEG-IFN) and ribavirin (RBV) for patients with chronic HCV infection.

METHODS

A total of 52 patients with high viral loads of HCV genotype 1b who were expected to respond well to therapy (rs8099917 TT genotype or relapse to previous therapy) were randomly assigned to two groups who were given 750 mg TVR at either 8 h (q8h) or 12 h (q12h) intervals in combination with PEG-IFN and RBV for 12 weeks, followed by 12 additional weeks of treatment with PEG-IFN and RBV alone. The primary end point of the study was undetectable HCV RNA at 12 weeks after the end of treatment (sustained virological response [SVR]12).

RESULTS

SVR12 rates were 92.3% (24/26) for both q8h and q12h. The changes in mean log10 HCV RNA levels and viral response were also similar in q8h compared to q12h, whereas pharmacokinetic properties such as maximum plasma concentration, area under the concentration-time curve at 24 h and trough plasma concentration of TVR were slightly higher in q8h than in q12h (P>0.2). The frequency of TVR discontinuation due to anaemia or renal damage was significantly higher in q12h than in q8h (6/26 [23%] versus 0/20 [0%], respectively; P=0.02).

CONCLUSIONS

TVR given at 12 h intervals should be considered for patients with lower body weight, especially patients with prior relapse and with IL28B polymorphisms at rs8099917 TT (interferon-λ 4 ss469415590 polymorphism TT/TT) genotype in patients with genotype 1b HCV infection.

Utility of controlled attenuation parameter measurement for assessing liver steatosis in Japanese patients with chronic liver diseases

AIM

Steatosis is a common histological feature of chronic liver disease, especially alcoholic and non-alcoholic fatty liver disease, as well as chronic hepatitis C. A recent study showed that evaluating the controlled attenuation parameter (CAP) with transient elastography was an efficient way of non-invasively determining the severity of hepatic steatosis. The objective of this study was to prospectively evaluate the utility of CAP for diagnosing steatosis in patients with chronic liver disease.

METHODS

One hundred and fifty-five consecutive patients with suspected chronic liver disease underwent steatosis diagnosis using CAP, blood sample analyses, computed tomography for assessing the liver/spleen ratio and liver biopsy. Steatosis was graded according to the percentage of fat-containing hepatocytes: S0, less than 5%; S1, 5-33%; S2, 34-66%; and S3: more than 66%.

RESULTS

The CAP was significantly correlated with steatosis grade, and there were significant differences between the CAP value of the S0 patients and those of the patients with other grades of steatosis. S0 and S1-3 hepatic steatosis were considered to represent mild and significant steatosis, respectively. The CAP values of the patients with mild and significant steatosis were significantly different (P < 0.0001). The area under the receiver-operator curve (AUROC) value of the CAP for diagnosing significant steatosis was 0.878 (95% confidence interval, 0.818-0.939), and the optimal CAP cut-off value for detecting significant steatosis was 232.5 db/m. In multivariate analysis, the CAP (P = 0.0002) and the liver to spleen ratio (P = 0.004) were found to be significantly associated with significant steatosis.

CONCLUSION

The CAP is a promising tool for rapidly and non-invasively diagnosing steatosis.

Hepatitis C virus genotype 1: how genetic variability of the core protein affects the response to pegylated-interferon and ribavirin therapy

Hepatitis C virus subgenotypes 1a and 1b are found worldwide and cause 60% of all hepatitis C cases. It has been reported recently that viral genetic variations have a critical impact on the patient treatment outcome. In particular, polymorphisms of the HCV core protein have been linked to poor treatment response. However, most of these studies were conducted on Asian populations, Japanese in particular who are infected with HCV subgenotype 1b. Hence, we aimed in this study to examine the core protein polymorphisms in Saudi patients who are infected with chronic HCV genotype 1 (1a and 1b subtypes) and its association with treatment outcome. Direct sequencing of full-length core protein and data mining analyses were utilized. Results have shown that the response to treatment is dependent on subgenotypes. Indeed, HCV-1b showed different point mutations that are associated with treatment outcome where the point mutations at positions 70 (Arg(70) Gln) and 75 (Thr(75) Ala) in HCV-1b are significantly associated with PEG-IFN/RBV treatment response. In contrast, HCV-1a showed no significant association between core protein mutations and response to treatment. In addition, analyses of HCV-1a core protein sequences revealed a highly conserved region especially in the responder group. This study provides a new insight in the genetic variability of full-length core protein in HCV genotype 1 in Saudi infected patients.

Therapeutic drug monitoring of telaprevir in chronic hepatitis C patients receiving telaprevir-based triple therapy is useful for predicting virological response

OBJECTIVES

This prospective, pharmacokinetic study was done to investigate the impact of telaprevir plasma trough concentration (Ctrough) in the early stage of treatment on the response to telaprevir-based triple therapy for chronic hepatitis C patients.

METHODS

Participants were 70 chronic hepatitis C patients infected with genotype 1. All patients received 12 week triple therapy that included telaprevir (2250 mg/day), pegylated interferon-α2b (pegylated-IFNα2b) (60-150 μg/week) and ribavirin (600-1000 mg/day) followed by a 12 week dual therapy that included pegylated-IFNα2b and ribavirin. Plasma telaprevir Ctrough was determined by a validated assay using HPLC at days 3, 7 and 14. The study was registered as a clinical trial on the University Hospital Medical Information Network (ID 000009656).

RESULTS

The rates of undetectable hepatitis C virus RNA at week 4 [rapid virological response (RVR)] and at 24 weeks after therapy [sustained virological response (SVR)] were 71.4% and 82.9%, respectively. Of the patients with RVR, 90% achieved SVR. The mean telaprevir Ctrough levels at days 3, 7 and 14 of SVR patients (2.748, 2.733 and 2.999 μg/mL, respectively) were significantly higher than those of non-SVR patients (1.616, 1.788 and 2.314 μg/mL, respectively) (all P < 0.05). Multiple logistic regression analysis of possible predictors of SVR extracted higher telaprevir Ctrough at day 3 (OR 1.012 by 0.001 μg/mL, P < 0.0001) and interleukin 28B (rs8099917) TT allele (OR 6.16 versus non-TT alleles, P < 0.0001).

CONCLUSIONS

Therapeutic drug monitoring of telaprevir in the early stage of treatment is useful in clinical practice for predicting the virological response of patients receiving telaprevir-based triple therapy.

Recent topics on α-fetoprotein

Zinc-fingers and homeoboxes 2 (ZHX2) and zinc-finger and BTB domain containing 20 (ZBTB20) repress the postnatal expression of α-fetoprotein (AFP) by interacting with the AFP gene promoter regions. ZHX2 inhibits the expression of AFP and cyclins A and E. ZBTB20 is negatively regulated by CUX1, which promotes cell-cycle progression, suggesting that AFP reactivation is closely linked to hepatocyte proliferation. A slight elevation in the serum AFP level often occurs in patients with chronic hepatitis C in the absence of hepatocellular carcinoma (HCC) and is an independent risk factor for HCC development to complement the fibrosis stage. In addition, the sustained elevation of AFP after interferon therapy is a risk factor of HCC development. AFP levels are clinically useful in predicting the outcomes of liver transplantation and sorafenib therapy for HCC patients. A low preoperative AFP level is a predictor of long-term survival and is associated with a low recurrence rate of HCC after liver transplantation. AFP response (≥20% decrease in AFP during 6-8 weeks of treatment) rather than radiological outcomes is a significant prognostic factor for survival in sorafenib-treated HCC patients. Highly sensitive Lens culinaris agglutinin-reactive AFP (AFP-L3) is 5-10 times more sensitive than conventional AFP-L3, and useful for early detection of HCC in patients with total AFP below 20 ng/mL.

Polymorphisms of the core, NS3, and NS5A proteins of hepatitis C virus genotype 1b associate with development of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the common sequelae of hepatitis C virus (HCV) infection. It remains controversial, however, whether HCV itself plays a direct role in the development of HCC. Although HCV core, NS3, and NS5A proteins were reported to display tumorigenic activities in cell culture and experimental animal systems, their clinical impact on HCC development in humans is still unclear. In this study we investigated sequence polymorphisms in the core protein, NS3, and NS5A of HCV genotype 1b (HCV-1b) in 49 patients who later developed HCC during a follow-up of an average of 6.5 years and in 100 patients who did not develop HCC after a 15-year follow-up. Sequence analysis revealed that Gln at position 70 of the core protein (core-Gln(70) ), Tyr at position 1082 plus Gln at 1112 of NS3 (NS3-Tyr(1082) /Gln(1112) ), and six or more mutations in the interferon/ribavirin resistance-determining region of NS5A (NS5A-IRRDR≥6) were significantly associated with development of HCC. Multivariate analysis identified core-Gln(70) , NS3-Tyr(1082) /Gln(1112) , and α-fetoprotein (AFP) levels (>20 ng/L) as independent factors associated with HCC. Kaplan-Meier analysis revealed a higher cumulative incidence of HCC for patients infected with HCV isolates with core-Gln(70) , NS3-Tyr(1082) /Gln(1112) or both than for those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ). In most cases, neither the residues at position 70 of the core protein nor positions 1082 and 1112 of the NS3 protein changed during the observation period.

CONCLUSION

HCV isolates with core-Gln(70) and/or NS3-Tyr(1082) /Gln(1112) are more closely associated with HCC development compared to those with non-(Gln(70) plus NS3-Tyr(1082) /Gln(1112) ).

Telaprevir can be successfully and safely used to treat older patients with genotype 1b chronic hepatitis C

BACKGROUND & AIMS

This study was performed to evaluate the efficacy of a triple therapy in older Japanese patients; telaprevir (TVR) was added to pegylated interferon α2b and ribavirin.

METHODS

This prospective study enrolled 120 genotype 1b patients with chronic hepatitis C who received 12 weeks of triple therapy followed by a 12-week dual therapy that included pegylated interferon α2b and ribavirin. Patients were categorized according to age: group A, 64 patients aged >60 and group B, 56 patients aged ⩽60. Serum HCV RNA levels were monitored by COBAS TaqMan HCV test.

RESULTS

The rates of undetectable HCV RNA at week 4 (rapid virological response, RVR) were 73.4% in group A and 73.2% in group B. No significant difference in sustained virological response (SVR) was found between groups A (76.6%) and B (83.9%) (p=0.314). The SVR rates for patients with interleukin 28B (IL28B) (rs8099917) TT allele (89.4% and 91.9% for groups A and B) were significantly higher than for those with the IL28B TG/GG allele (41.2% and 68.4%, respectively) (both p<0.05). Multivariate analysis extracted IL28B TT and RVR as independent factors associated with SVR. Adverse effects resulted in treatment discontinuation by 12.5% in each group. Hemoglobin decrease significantly differed between groups A and B: the decrease to ≤100 g/L, to 85 - <100g/L, and to <85 g/L, was 9.4%, 40.6%, and 50% in group A patients, respectively, and 41.1%, 25%, and 33.9% in group B patients, respectively (p=0.0006).

CONCLUSIONS

TVR-based triple therapy can be successfully used to treat older patients with genotype 1b chronic hepatitis C.

Role of different regions of the hepatitis C virus genome in the therapeutic response to interferon-based treatment

Hepatitis C virus (HCV) is considered a significant risk factor in HCV-induced liver diseases and development of hepatocellular carcinoma (HCC). Nucleotide substitutions in the viral genome result in its diversification into quasispecies, subtypes and distinct genotypes. Different genotypes vary in their infectivity and immune response due to these nucleotide/amino acid variations. The current combination treatment for HCV infection is pegylated interferon α (PEG-IFN-α) with ribavirin, with a highly variable response rate mainly depending upon the HCV genotype. Genotypes 2 and 3 are found to respond better than genotypes 1 and 4, which are more resistant to IFN-based therapies. Different studies have been conducted worldwide to explore the basis of this difference in therapy response, which identified some putative regions in the HCV genome, especially in Core and NS5a, and to some extent in the E2 region, containing specific sequences in different genotypes that act differently with respect to the IFN response. In the review, we try to summarize the role of HCV proteins and their nucleotide sequences in association with treatment outcome in IFN-based therapy.

Exploratory study on telaprevir given every 8 h at 500 mg or 750 mg with peginterferon-alpha-2b and ribavirin in hepatitis C patients

AIM

The aims of this study are to assess the antiviral effects, safety and telaprevir (TVR) pharmacokinetics in two cohorts given TVR every 8 h (q8h) at doses of 500 mg and 750 mg with peginterferon-α-2b and ribavirin in chronic hepatitis C patients.

METHODS

Twenty chronic hepatitis C (HCV) patients with genotype 1b in high viral loads were randomly assigned to two TVR-based regimens of 750 mg q8h (group A) and 500 mg q8h (group B) in combination with peginterferon-α-2b and ribavirin for 12 weeks.

RESULTS

Although the difference was not statistically significant other than trough concentration (Ctrough ) at week 4, the parameters of maximum concentration (Cmax ), the area under the concentration time curve (AUC0-∞ ) and Ctrough tended to be higher in group A than those in group B. The antiviral effects were similar in the two groups (sustained virological response rates [SVR], 40% in group A, 50% in group B). The discontinuation rates by anemia were 30% in group A and 20% in group B. Serum creatinine concentrations were lower in group B than those in group A.

CONCLUSION

Although the exposure to TVR tended to be lower in 500 mg q8h than that in 750 mg q8h, the SVR rates in both groups were similar. The result suggests that the 500 mg q8h dose may be one option for treatment. In addition, the present findings indicate that the development of adverse events which increase with a TVR-based regimen, specifically anemia and creatinine, could be avoided by dose adjustment of TVR.

Serum lipoprotein profiles and response to pegylated interferon plus ribavirin combination therapy in patients with chronic HCV genotype 1b infection

BACKGROUND

Abnormal serum lipid profiles have been noted in patients with chronic hepatitis C virus (HCV) infection. Moreover, many reports suggest that serum lipoprotein profiles are more profoundly distorted in patients with HCV G1b infection who have an unfavorable response to pegylated interferon (peg-IFN) plus ribavirin (RBV) combination therapy. However, after the discovery of single nucleotide polymorphisms near the IL28B gene (rs8099917 and rs12979860) as potent predictive factors affecting the response to peg-IFN plus RBV, lipid factors are thought to be confounding factors.

OBJECTIVES

To re-examine the significance of lipoprotein profiles on virological response to peg-IFN plus RBV combination therapy in patients with chronic HCV G1b infection, we examined cholesterol and triglyceride concentrations in each lipoprotein fraction separated by high performance liquid chromatography.

PATIENTS AND METHODS

Lipoprotein profiles were examined using fasting sera from 108 patients infected with HCV G1b who had chronic hepatitis, as determined by liver biopsy. Results of lipoprotein profiles and clinical data, including IL28B genotype and amino acid substitution at aa70 of HCV G1b, were compared between patients with a sustained virological response (SVR) and non-SVR or a non-virological response (NVR) and virological responses other than NVR (non-NVR). In addition, significant predictive factors independently associated with virological response to peg-IFNα-2b plus RBV were determined by logistic regression analysis.

RESULTS

An increased ratio of cholesterol/triglyceride in very low-density lipoprotein (odds ratio (OR) 3.03; 95% confidence interval (CI) 1.01-9.44) along with a major genotype of rs8099917 (OR 9.09; 95% CI 2.94-33.33), were independent predictive factors for SVR. In contrast, lipid factors were not elucidated as independent predictive factors for NVR.

CONCLUSIONS

Examination of the fasting lipid profile has clinical importance in predicting the efficacy of peg-IFN-α-2b plus RBV combination therapy for patients with HCV G1b even after the discovery of the IL28 genotype as a potent predictive factor.

Hepatitis C virus, cholesterol and lipoproteins--impact for the viral life cycle and pathogenesis of liver disease

Hepatitis C virus (HCV) is a leading cause of chronic liver disease, including chronic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Hepatitis C infection associates with lipid and lipoprotein metabolism disorders such as hepatic steatosis, hypobetalipoproteinemia, and hypocholesterolemia. Furthermore, virus production is dependent on hepatic very-low-density lipoprotein (VLDL) assembly, and circulating virions are physically associated with lipoproteins in complexes termed lipoviral particles. Evidence has indicated several functional roles for the formation of these complexes, including co-opting of lipoprotein receptors for attachment and entry, concealing epitopes to facilitate immune escape, and hijacking host factors for HCV maturation and secretion. Here, we review the evidence surrounding pathogenesis of the hepatitis C infection regarding lipoprotein engagement, cholesterol and triglyceride regulation, and the molecular mechanisms underlying these effects.

Baseline factors and early viral response (week 4) to antiviral therapy with peginterferon and ribavirin for predicting sustained virologic response in patients infected with hepatitis C virus genotype 1: a multicenter study

Both baseline predictive factors and viral response at week 4 of therapy are reported to have high predictive ability for sustained virologic response to peginterferon and ribavirin combination therapy in patients with hepatitis C virus (HCV) genotype 1. However, it is not clear how these baseline variables and week 4 response should be combined to predict sustained virologic response. In this multicenter study, the authors investigated the impact of baseline predictive factors on the predictive value of week 4 viral response. Receiver-operating characteristic curve analyses were performed to evaluate the ability of week 4 reduction in HCV RNA levels to predict sustained virologic response in 293 Japanese patients infected with HCV genotype 1b. Analyses were performed in all patients and in patient subgroups stratified according to baseline variables. Overall, week 4 viral reduction demonstrates a high predictive ability for sustained virologic response. The sensitivity, specificity, positive predictive value (PPV), negative predictive value, and accuracy were higher than those of viral reduction at week 12. However, the best cut-off levels differ depending on the baseline factors and they were lower in patients with unfavorable baseline predictors. When patients had the TG/GG rs8099917 genotype, the best cut-off was markedly low with low PPV. Week 4 viral response can be a predictor of sustained virologic response in patients with HCV genotype 1 and is better than week 12 viral response. However, the cut-off levels should be modified based on the baseline predictive variables.

IL28B polymorphism and cytomegalovirus predict response to treatment in Egyptian HCV type 4 patients

AIM

To test whether the status of positive cytomegalovirus (CMV) DNA detection adds to the predictive value of IL28B and to further categorize C/T allele carriers.

METHODS

This study included 166 chronic hepatitis C (CHC) patients who received combined interferon and ribavirin therapy for 48 wk, 84 spontaneous hepatitis C virus (HCV) resolvers who were positive for IgG anti-HCV antibody and negative for HCV RNA, and 100 healthy subjects who were negative for both HCV antibodies and RNA as controls. Genomic DNA from peripheral blood was used for IL28B rs.12979860 single nucleotide polymorphism (SNP) and CMV DNA detection. A 139 bp fragment containing IL28B SNP was amplified in all subjects by polymerase chain reaction using a specifically designed primer. Then the IL28B rs.12979860 SNP was detected by restriction fragment length polymorphism (RFLP) genotyping. The presence of CMV DNA was tested by amplification of the gB1 gene using nested polymerase chain reaction. The role of CMV and IL28B rs.12979860 SNP genotypes in determining the response rate to combined interferon therapy and clinical status of patients were statistically analyzed.

RESULTS

Current data showed that 67% of patients carrying the IL28B 12979860 C/C allele had a sustained viral response (SVR) while the genotypes C/T and TT were associated with lower SVR rates, 50% and 48%, respectively. SVR rates for the C/C allele were lower than other HCV genotypes and/or other populations. Genotype CC was associated with the response to interferon (P = 0.025). Genotype C/C was reduced from 48% in controls to 14% in CHC patients suggesting its protective role against progression to chronicity. The majority of spontaneously cleared subjects (86%) were C/C, confirming its protective role. The C/T allele was present in 71% of CHC patients compared with 38% of controls, so the use of IL28B SNP genotyping only in these patients may be of little value as a predictor of response. CMV reactivation occurred in 40% of CHC patients. Co-infection with CMV seriously diminished the response to interferon (IFN) therapy, with SVR rates in C/C genotypes 87.5% in CMV-negative patients and 12.5% in CMV-positive patients (P < 0.0001). SVR rates among C/T carriers were reduced to < 50% in patients with positive CMV DNA while the non-response rate doubled. These data indicate that a supplemental assay for CMV viremia adds to the prognostic value of IL28B genotyping.

CONCLUSION

The results suggest that both genetic (i.e., spontaneous) and therapeutic (IFN-based therapy) arms are complementary in the battle against HCV. CMV DNA testing may be of value to better predict the response to IFN, particularly in IL28B C/T carriers.

A multicenter survey of re-treatment with pegylated interferon plus ribavirin combination therapy for patients with chronic hepatitis C in Japan

AIM

  This study aimed to clarify the factors associated the efficacy of re-treatment with pegylated interferon (PEG IFN) plus ribavirin combination therapy for patients with chronic hepatitis C who had failed to respond to previous treatment.

METHODS

  One hundred and forty-three patients who had previously shown relapse (n = 79), non-response (n = 34) or intolerance (n = 30) to PEG IFN plus ribavirin were re-treated with PEG IFN plus ribavirin.

RESULTS

  Twenty-five patients with intolerance to previous treatment completed re-treatment and the sustained virological response (SVR) rates were 55% and 80% for hepatitis C virus (HCV) genotype 1 and 2, respectively. On re-treatment of the 113 patients who completed the previous treatment, the SVR rates were 48% and 63% for genotype 1 and 2, respectively. Relapse after previous treatment and a low baseline HCV RNA level on re-treatment were associated with SVR in genotype 1 (P < 0.001). Patients with the interleukin-28B major genotype responded significantly better and earlier to re-treatment, but the difference in the SVR rate did not reach a significant level between the major and minor genotypes (P = 0.09). Extended treatment of 72 weeks raised the SVR rate among the patients who attained complete early virological response but not rapid virological response with re-treatment (72 weeks, 73%, 16/22, vs 48 weeks, 38%, 5/13, P < 0.05).

CONCLUSION

  Relapse after previous treatment and a low baseline HCV RNA level have predictive values for a favorable response of PEG IFN plus ribavirin re-treatment for HCV genotype 1 patients. Re-treatment for 72 weeks may lead to clinical improvement for genotype 1 patients with complete early virological response and without rapid virological response on re-treatment.

Treatment of chronic hepatitis C virus infection in Japan: update on therapy and guidelines

Hepatitis C virus (HCV) infection is a serious health problem leading to cirrhosis, liver failure and hepatocellular carcinoma. The recent introduction of telaprevir, which was approved in November 2011, in combination with peg-interferon and ribavirin is expected to markedly improve the eradication rate of the virus. However, side effects of triple therapy may be severe. In a phase three III clinical trial, 2250 mg of telaprevir, which is the same dosage used in clinical trials in Western countries, was given to Japanese patients. As this dosage is considered to be relatively high for Japanese patients, who typically have lower weight than patients in Western countries, reduction of telaprevir is recommended in the 2012 revision of the guidelines established by the Study Group for the Standardization of Treatment of Viral Hepatitis Including Cirrhosis published by the Ministry of Health, Labour and Welfare of Japan. Other protease inhibitors with fewer side effects are now in clinical trials in Japan. Alternatively, treatment of patients with combination of direct acting antivirals without interferon has been reported. In this review we summarize current treatment options in Japan and discuss how we treat patients with chronic HCV infection.

Sex hormones and HCV: an unresolved mystery

The biological differences between males and females advocate the ultimate need for gender-specific medicine. The variation in response to viral infection as well as therapy among different genders makes it very intriguing to reveal the responsible factors for causing this discrepancy. HCV is one of the most noxious infectious diseases, however the impact of gender on the response to HCV has received negligible attention in the literature. The controversial studies concerning the effect of gender on the outcome of interferon-based therapy urge a need to judge the gender discrepancy in host factors responsible for both interferon release and action. The main aim of this review is to disentangle the interplay between sex hormones and several viral and host factors responsible for viral clearance in an attempt to clarify the role of gender in modulating the response to HCV as well as interferon-based therapy.

Changes in sequences of core region, interferon sensitivity-determining region and interferon and ribavirin resistance-determining region of hepatitis C virus genotype 1 during interferon-alpha and ribavirin therapy, and efficacy of retreatment

AIM

  Some regions associated with sensitivity to interferon-α and ribavirin have been identified in the hepatitis C virus (HCV) genome, including amino acid 70 in the core region (core a.a. 70), a.a. 2209-2248 (interferon sensitivity-determining region, ISDR) and a.a. 2334-2379 (interferon and ribavirin resistance-determining region, IRRDR).

METHODS

  We examined changes in the sequences of these regions in 25 patients with chronic HCV genotype 1 infection who had not had sustained virological response (SVR) to interferon-α and ribavirin for 24-48 weeks and subsequently received retreatment for 48-72 weeks.

RESULTS

  At baseline, the core a.a. 70 was mutant (resistant) type in seven patients. At the start of retreatment, the core a.a. 70 had changed from sensitive to resistant type in 2 patients, and SVR was not achieved by retreatment. The ISDR variations were resistant type (0-1 mutations) in 17 patients at baseline. After 2 weeks of treatment, amino acid change was found in two patients; in one, the substitutions returned to baseline status after treatment, and in the other, the substitution persisted. At the start of retreatment, ISDR sequences had changed from resistant to sensitive type in two patients and SVR was achieved and from sensitive to resistant type in three patients and SVR was not achieved. The IRRDR variations were resistant type (<6 mutations) in 19 patients at baseline and at the start of retreatment.

CONCLUSION

  Sequences of the core region and ISDR sometimes change during anti-HCV therapy, potentially affecting the outcomes of retreatment.

Complicated relationships of amino acid substitution in hepatitis C virus core region and IL28B genotype influencing hepatocarcinogenesis

The impact of amino acid (aa) 70 substitution in the core region on hepatocarcinogenesis and survival for liver-related death in patients of hepatitis C virus (HCV) genotype 1b (HCV-1b), who had not received antiviral therapy, is unknown. The relationships among aa 70 substitution, IL28B genotype, and hepatocarcinogenesis are also not clear. A total of 1,181 consecutive HCV-infected patients, who had not received antiviral therapy, were included in a follow-up study to determine predictive factors of hepatocarcinogenesis and survival for liver-related death. The cumulative hepatocarcinogenesis rates in HCV-1b of Gln70(His70) (glutamine (histidine) at aa 70) were significantly higher than those in HCV-1b of Arg70 (arginine at aa 70) and HCV-2a/2b. The cumulative survival rates for liver-related death in HCV-1b of Gln70(His70) were significantly lower than those in HCV-1b of Arg70 and HCV-2a/2b. Multivariate analysis identified gender (male), age (≥ 60 years), albumin (<3.9 g/dL), platelet count (<15.0 × 10(4) /mm(3) ), aspartate aminotransferase (≥ 67 IU/L), and HCV subgroup (HCV-1b of Gln70(His70)) as determinants of both hepatocarcinogenesis and survival rates for liver-related death. In HCV-1b patients, the cumulative change rates from Arg70 to Gln70(His70) by direct sequencing were significantly higher than those from Gln70(His70) to Arg70. In patients of Arg70 at the initial visit, the cumulative change rates from Arg70 to Gln70(His70) in IL28B rs8099917 non-TT genotype were significantly higher than those in the TT genotype.

CONCLUSION

Substitution of aa 70 in the core region of HCV-1b is an important predictor of hepatocarcinogenesis and survival for liver-related death in HCV patients who had not received antiviral therapy. The IL28B genotype might partly affect changes over time of dominant amino acid in core aa 70 of HCV-1b.

A lower serum gamma-glutamyltransferase level does not predict a sustained virological response in patients with chronic hepatitis C genotype 1

Background/Aims

Low gamma-glutamyltransferase (GGT) level was shown to be an independent predictor of a sustained virological response (SVR) in chronic hepatitis C. We aimed to determine factors associated with high GGT level, and to evaluate whether low GGT level is an independent predictor of a SVR in chronic hepatitis C genotype 1.

Methods

We retrospectively reviewed our data of patients with chronic hepatitis C genotype 1 treated with pegylated interferon-α and ribavirin. Baseline features were compared between patients with normal and high GGT levels. Factors associated with high GGT level and those associated with a SVR were determined by univariate and multivariate analysis.

Results

This study included 57 patients. Mean age was 52.28±9.35 years. GGT levels was elevated in 27 patients (47.4%). GGT levels were normal in 63.3% of the patients who achieved a SVR and in 40.7% of those who did not achieve a SVR (p>0.05). By multivariate logistic regression analysis, the presence of cirrhosis (odds ratio [OR], 9.41; 95% confidence interval [CI], 1.08 to 102.61) and female gender (OR, 6.77; 95% CI, 1.23 to 37.20) were significantly associated with high GGT level, and only rapid virological response was associated with a SVR (OR, 8.369; 95% CI, 1.82 to 38.48).

Conclusions

Low GGT level does not predict a SVR; however, it may be a predictor of high fibrosis scores.

Amino acid substitutions in the Hepatitis C virus core region of genotype 1b in Moroccan patients

The aim of the present study was to identify basic amino acid in the core region in subtype 1b-infected, treatment-naive patients from Morocco and to search for their eventual association with liver cancer. The survey included 151 patients (86 patients with chronic hepatitis and 65 patients with hepatocellular carcinoma, HCC). We performed direct sequencing, and compared the data obtained with the consensus sequence of core protein. Several recurrent amino acid substitutions were observed. The Arg70 was changed for a Gln in 22 of 112 patients (19.6%) and Leu91 was changed to Met in 23 of 112 patients (20.5%). Besides, the threonine at position 75 (Thr75) was mutated for alanine or serine in 43 (38.4%) and 40 (35.7%) of the patients, respectively. Overall, there was no significant difference between patients with chronic hepatitis and those with HCC regarding amino acids substitution number (24% vs. 33%, respectively, P = 0.457). Our study provides the first inventory of predominant amino acid substitutions in the HCV core region genotype 1b. The impact of single or combined mutations on the resistance to treatment or on disease progression is still unknown and deserves more attention in the future.

High serum palmitic acid is associated with low antiviral effects of interferon-based therapy for hepatitis C virus

Hepatitis C virus (HCV) infection alters fatty acid synthesis and metabolism in association with HCV replication. The present study examined the effect of serum fatty acid composition on interferon (IFN)-based therapy. Fifty-five patients with HCV were enrolled and received IFN-based therapy. Patient characteristics, laboratory data (including fatty acids), and viral factors that could be associated with the anti-HCV effects of IFN-based therapy were evaluated. The effects of individual fatty acids on viral replication and IFN-based therapy were also examined in an in-vitro system. Multivariate logistic regression analysis showed that the level of serum palmitic acid before treatment and HCV genotype were significant predictors for rapid virological response (RVR), early virological response (EVR), and sustained virological response (SVR). High levels of palmitic acid inhibited the anti-HCV effects of IFN-based therapy. HCV replication assays confirmed the inhibitory effects of palmitic acid on anti-HCV therapy. The concentration of serum palmitic acid is an independent predictive factor for RVR, EVR, and SVR in IFN-based antiviral therapy. These results suggest that the effect of IFN-based antiviral therapy in patients with HCV infection might be enhanced by treatment that modulates palmitic acid levels.

Efficacy and anticarcinogenic activity of ribavirin combination therapy for hepatitis C virus-related compensated cirrhosis

OBJECTIVE

Anticarcinogenic activity of ribavirin combination therapy for hepatitis C virus (HCV)-related compensated cirrhosis is still unclear.

METHODS

In study 1, in 157 consecutive patients with HCV-related compensated cirrhosis, treatment efficacy with interferon plus ribavirin therapy was evaluated for 48 weeks of HCV genotype 1b (HCV-1b) or 24 weeks of HCV-2a/2b. In study 2, in 185 consecutive patients with HCV-related compensated cirrhosis, who showed no sustained virological response following the first course of interferon monotherapy, hepatocarcinogenesis rates were evaluated according to the additional treatment, and they were classified into three groups: no treatment, interferon monotherapy, and ribavirin combination therapy.

RESULTS

In study 1, in HCV-1b, rates of sustained virological response and sustained biochemical response were 21 and 56%, respectively. In HCV-2a/2b, rates of sustained virological response and sustained biochemical response were 70 and 78%, respectively. In HCV-1b, sustained biochemical response rates were significantly higher than those of sustained virological response. In study 2, the hepatocarcinogenesis rates in ribavirin combination therapy were significantly lower than those in interferon monotherapy and no treatment, respectively.

CONCLUSION

Ribavirin combination therapy for HCV-related compensated cirrhosis reduces the risk of hepatocarcinogenesis in comparison with interferon monotherapy, and higher rates of sustained biochemical response might be associated with lower hepatocarcinogenesis rates.

Prediction of response to pegylated interferon/ribavirin combination therapy for chronic hepatitis C genotype 1b and high viral load

BACKGROUND

This study explores pretreatment predictive factors for ultimate virological responses to pegylated interferon-α (1.5 μg/kg/week) and ribavirin (600-1000 mg/day) (PEG-IFN/RBV) combination therapy for patients infected with hepatitis C virus (HCV)-1b and a high viral load.

METHODS

A total of 75 patients underwent PEG-IFN/RBV combination therapy for 48 weeks. HCV amino acid (aa) substitutions in non-structural protein 5a, including those in the IFN/RBV resistance-determining region (IRRDR) and the IFN sensitivity-determining region and the core regions, as well as the genetic variation (rs8099917) near the interleukin 28B (IL28B) gene (genotype TT) were analyzed.

RESULTS

Of the 75 patients, 49 % (37/75) achieved a sustained virological response (SVR), 27 % (20/75) showed relapse, and 24 % (18/75) showed null virological response (NVR). Multivariate logistic regression analysis identified IRRDR with 6 or more mutations (IRRDR ≥6) [odds ratio (OR) 11.906, p < 0.0001] and age <60 years (OR 0.228, p = 0.015) as significant determiners of SVR and IL28B minor (OR 14.618, p = 0.0019) and platelets <15 × 10(4)/mm(3) (OR 0.113, p = 0.0096) as significant determiners of NVR. A combination of IRRDR ≥6 and age <60 years improved SVR predictability (93.3 %), and that of IRRDR ≤5 and age ≥60 years improved non-SVR predictability (84.0 %). Similarly, a combination of IL28B minor and platelets <15 × 10(4)/mm(3) improved NVR predictability (85.7 %), and that of IL28B major and platelets ≥15 × 10(4)/mm(3) improved non-NVR (response) (97.1 %) predictability.

CONCLUSION

IRRDR ≥6 and age <60 years were significantly associated with SVR. IL28B minor and platelets <15 × 10(4)/mm(3) were significantly associated with NVR. Certain combinations of these factors improved SVR and NVR predictability and could, therefore, be used to design therapeutic strategies.

NS5A sequence heterogeneity of hepatitis C virus genotype 4a predicts clinical outcome of pegylated-interferon-ribavirin therapy in Egyptian patients

Hepatitis C virus genotype 4 (HCV-4) is the cause of approximately 20% of the 180 million cases of chronic hepatitis C in the world. HCV-4 infection is common in the Middle East and Africa, with an extraordinarily high prevalence in Egypt. Viral genetic polymorphisms, especially within core and NS5A regions, have been implicated in influencing the response to pegylated-interferon and ribavirin (PEG-IFN/RBV) combination therapy in HCV-1 infection. However, this has not been confirmed in HCV-4 infection. Here, we investigated the impact of heterogeneity of NS5A and core proteins of HCV-4, mostly subtype HCV-4a, on the clinical outcomes of 43 Egyptian patients treated with PEG-IFN/RBV. Sliding window analysis over the carboxy terminus of NS5A protein identified the IFN/RBV resistance-determining region (IRRDR) as the most prominent region associated with sustained virological response (SVR). Indeed, 21 (84%) of 25 patients with SVR, but only 5 (28%) of 18 patients with non-SVR, were infected with HCV having IRRDR with 4 or more mutations (IRRDR ≥ 4) (P = 0.0004). Multivariate analysis identified IRRDR ≥ 4 as an independent SVR predictor. The positive predictive value of IRRDR ≥ 4 for SVR was 81% (21/26; P = 0.002), while its negative predictive value for non-SVR was 76% (13/17; P = 0.02). On the other hand, there was no significant correlation between core protein polymorphisms, either at residue 70 or at residue 91, and treatment outcome. In conclusion, the present results demonstrate for the first time that IRRDR ≥ 4, a viral genetic heterogeneity, would be a useful predictive marker for SVR in HCV-4 infection when treated with PEG-IFN/RBV.

Determinants of response to triple therapy of telaprevir, peginterferon, and ribavirin in previous non-responders infected with HCV genotype 1

Patients who do not achieve sustained virological response to telaprevir/peginterferon (PEG-IFN)/ribavirin need to be identified. Predictive factors of virological response to the triple therapy in non-responders to previous PEG-IFN/ribavirin therapy are not clear. The aims of this study were to determine the predictive factors of virological response to a 24-week regimen of triple therapy in 15 non-responders to previous PEG-IFN/ribavirin therapy among 61 Japanese adults infected with HCV genotype 1. Overall, sustained virological response and end-of-treatment response were achieved by 27% and 60%, respectively. Telaprevir-resistant variants (by direct sequencing) appeared during or after treatment in 82% of patients who did not show sustained virological response, but disappeared at the end of study, except for one patient with resistant variant at baseline. Substitution at aa 70 (Arg70) and type of previous response to PEG-IFN/ribavirin (partial response) were identified as significant determinants of sustained virological response. In addition, alpha-fetoprotein level (<10 µg/L) and type of previous response (partial response) were identified as significant determinants of end-of-treatment response. Prediction of response to therapy based on the combination of these factors had high sensitivity, specificity, positive, and negative predictive values. In conclusion, this study identified amino acid substitution of the core region, alpha-fetoprotein level, and type of previous response as predictors of virological response to telaprevir/PEG-IFN/ribavirin in patients infected with HCV genotype 1b who had not responded to previous PEG-IFN/ribavirin therapy.

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.

Comparison of three different methods for the evaluation of IL28 and ITPA polymorphisms in patients infected with HCV

A single nucleotide polymorphism (SNP) upstream of the IL28 gene (rs12979860) has been reported to predict sustained virological response to peginterferon-ribavirin therapy in chronic HCV patients. In addition, two functionally deficient variants (rs1127354 and rs7270101) of inosine triphosphatase (ITPA) were shown to protect against ribavirin (RBV) - induced hemolytic anemia during early stages of treatment. In this study, three methods for detecting IL28 and ITPA mutations were compared to evaluate accuracy, sensitivity costs and turn-around time. IL28 and ITPA variants were detected using genomic DNA from peripheral blood mononuclear cells (PBMCs) of 61 patients with chronic HCV infection by denaturing high-performance liquid chromatography (DHPLC), direct DNA sequencing analysis and Taq Man Real-Time SNP analysis. Complete concordance in the IL28 polymorphism analysis was observed among the three methods. As for ITPA polymorphisms, 60/61 (98.4%) samples were consistent among the three methods, while results for 1/61 (1.64%) samples were concordant by DHPLC and sequencing, and discordant by real-time SNP. All three methods are suitable for routine testing. On the other hand, screening by real-time SNP detection was less expensive and more rapid.

An open-label randomized controlled study of pegylated interferon/ribavirin combination therapy for chronic hepatitis C with versus without fluvastatin

Pegylated interferon (PEG-IFN)/ribavirin combination therapy is the standard-of-care (SOC) treatment for chronic hepatitis C patients infected with hepatitis C virus (HCV) genotype 1b and high viral load. The addition of fluvastatin to SOC treatment has been suggested to be effective for better outcome in retrospective pilot analyses. We investigated whether the combination of fluvastatin with PEG-IFN/ribavirin could actually improve sustained viral response (SVR) in patients with HCV genotype 1b and high viral load. A randomized, open-labeled, controlled study was conducted between July 2008 and December 2009 in 101 chronic hepatitis C patients allocated to PEG-IFN/ribavirin combination therapy with or without fluvastatin. SVR rates were calculated in groups, stratifying host and viral factors. We also analyzed predictive factors for SVR among patients on fluvastatin with multivariate regression analysis. Rapid and early virological, and end of treatment response rates in the fluvastatin group were not significantly different from those in the non-fluvastatin group. Notwithstanding, SVR rate was significantly higher in the fluvastatin group than in the non-fluvastatin group (63.0%vs 41.7%, P = 0.0422). Comparison of the two groups stratifying demographic data and HCV characteristics showed significantly higher SVR rates to more than 80% in males, more than two mutations in the interferon sensitivity determining region (ISDR), and a history of relapse among the fluvastatin group than the non-fluvastatin group. Being male and major genotype IL28B single nucleotide polymorphisms (SNPs) were independent predictive factors for SVR among patients on fluvastatin with multivariate analysis. Fluvastatin-combined with PEG-IFN/ribavirin therapy significantly improves SVR rates in patients with HCV genotype 1b and high viral load. Male and major genotype IL28B SNPs were independent predictors for SVR among patients on fluvastatin combination therapy.

Impact of interleukin-28B genotype on in vitro and in vivo systems of hepatitis C virus replication

Identification of the relationship between the interleukin (IL)-28B genotype and the effect of peginterferon plus ribavirin treatment has had a great impact on the study of antiviral therapy for patients with chronic hepatitis C virus (HCV) infection. Differential expression levels of interferon-stimulated genes (ISG) in the liver and white blood cells based on the IL-28B genotype, which may in turn lead to differences in outcome of therapy, indicate that previous studies should be re-evaluated taking the effect of the IL-28B single nucleotide polymorphism (SNP) into consideration, although the exact mechanism of how variation in IL-28B SNPs affect HCV eradication remains unknown. These results suggest that the genotypes of multiple cell types, including liver and immune cells, contribute to the efficacy of therapy. Studies using human hepatocyte chimeric mice, in which effector cells of the human adaptive immune response are absent, showed that viral load, ISG expression levels and reduction of HCV RNA by interferon are affected by the IL-28B genotype. Genetic differences among hepatocytes may, therefore, contribute to differences in baseline viral loads and response to interferon therapy. Further studies should be done to clarify the mechanism of action of IL-28B SNP on viral load and effect of interferon treatment. Advances in cell culture systems and human hepatocyte chimeric mice, as well as upcoming in vitro and in vivo experimental systems, provide an effective platform to examine the effects of host and viral genetic variation on infection and response to interferon.

Amino acid substitutions in the hepatitis C Virus core region and lipid metabolism are associated with hepatocarcinogenesis in nonresponders to interferon plus ribavirin combination therapy

BACKGROUND

Substitution of amino acid 70 and/or 91 in the core region of hepatitis C virus (HCV) genotype 1b (HCV-1b) is an important predictor of hepatocellular carcinoma (HCC), but its impact on HCC in nonresponders to interferon (IFN) and ribavirin (RIB) combination therapy is not clear.

METHODS

A total of 292 patients with HCV-1b-related chronic liver disease who did not achieve a sustained virological response to 24-48 weeks of IFN+RIB combination therapy were included in a follow-up study to investigate the risk factors for HCC.

RESULTS

Sixteen patients developed HCC during the follow-up. The cumulative HCC rates were 5.0, 13.1 and 16.9% at the end of 3, 5 and 7 years, respectively. Multivariate analysis identified substitution of core amino acid 70 (Gln70/His70; hazard ratio 4.64, p = 0.018) and low serum levels of high-density lipoprotein cholesterol (<50 mg/dl; hazard ratio 9.35, p = 0.041) as determinants of HCC. Gender, stage of fibrosis and interleukin-28B showed no such relationship.

CONCLUSIONS

Amino acid substitution in the core region of HCV-1b and low serum levels of high-density lipoprotein cholesterol are significant and independent predictors of HCC in nonresponders to IFN+RIB combination therapy. These results emphasize the importance of viral and lipid metabolic factors in the development of HCC after combination therapy.

The role of viral and host genetics in natural history and treatment of chronic HCV infection

Understanding of the natural history and treatment responsiveness of chronic hepatitis C virus (HCV) infection has evolved rapidly in recent years. Advances in HCV molecular virology and host genetics can now better predict spontaneous clearance and treatment outcomes. HCV genotype is the most important viral factor predicting interferon-α treatment responsiveness; HCV-1 subtype is emerging as a key determinant of the efficacy of direct acting antiviral therapy. Genome-wide association studies have recently identified several clinically important host determinants of the outcomes of peginterferon-α and ribavirin treatment outcome: IL28B polymorphism is associated with spontaneous clearance and treatment responsiveness; ITPA polymorphism protects against ribavirin-induced anaemia and dose reductions; genetic determinants of liver fibrosis progression rate have been proposed. In this review, we evaluate the role of viral and host genetics in the natural history and treatment outcomes of chronic HCV infection, and consider how this knowledge might help individualize clinical management in the era of DAA therapy.

Genomic variation-guided management in chronic hepatitis C

In 2009, several different research groups simultaneously identified the polymorphisms close to IL28B gene as an important predictor of therapeutic response for chronic hepatitis C (CHC) patients receiving interferon-based treatment using approaches of genome-wide association studies. They also found that these genetic variations were strongly associated with the spontaneous viral clearance of hepatitis C virus (HCV) infection. Following these studies, ITPA gene variants were reported to affect ribavirin-induced anemia and therapeutic outcomes of CHC patients. All these lines of evidence usher in a new genomic era for the management of HCV infection. In this article, advances in recent genome-wide association studies regarding HCV infection, and their impacts on the management of CHC patients will be reviewed. In addition, the clinical usefulness of genomic variations on the addition of direct antiviral agents to current standard of care will be discussed.

Identification of novel HCV deletion mutants in chronic hepatitis C patients

BACKGROUND

The HCV genome consists of a positive 9.6 kb single-strand of RNA. Nucleotide substitutions in the HCV genome are common and a 2 kb deletion has been reported.

METHODS

A total of 117 chronic hepatitis C (CHC) patients who were treated with pegylated interferon plus ribavirin combination therapy were enrolled in this study. Total RNA was extracted from the patients' sera and reverse transcription and PCR were performed. Statistical analysis was performed to evaluate the effects of HCV deletion mutants on treatment with combination therapy.

RESULTS

By amplifying entire HCV genomes using long-distance PCR, novel large deletion mutants were identified. Sequence analysis revealed that these deletions extended approximately 6 kb from the core/E2 region to the NS5A region and that there are three kinds of deletions that are identical at their 3' and 5' extremities. The subgenome virus particles appeared to coexist with full-genome virus particles in the sera of CHC patients despite lacking essential components for HCV viral replication. These short fragments were detected in 26 of 117 patients and were associated with significantly higher HCV RNA levels (P=0.018) and poor response to combination therapy (P=0.043). Moreover, the existence of HCV deletion mutants was significantly associated with virological relapse following combination therapy (P=0.046, OR=3.4).

CONCLUSIONS

HCV deletion mutants may affect the HCV life cycle and reduce the antiviral effects of interferon therapy for CHC.

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 substitution in HCV core region and genetic variation near the IL28B gene affect viral dynamics during telaprevir, peginterferon and ribavirin treatment

OBJECTIVES

Genetic variation near the IL28B gene and substitution of aa 70 and 91 in the core region of HCV-1b are useful as predictors of treatment efficacy to telaprevir/pegylated interferon (PEG-IFN)/ribavirin, but its impact on viral dynamics is not clear.

METHODS

This study investigated predictive factors of viral dynamics during 12- or 24-week regimen of triple therapy in 80 Japanese adults infected with HCV-1b.

RESULTS

After 24 h of commencement of treatment, the proportion of patients with Arg70 and Leu91 substitutions in the core region who showed ≥3.0 log drop in HCV RNA level was significantly higher than that of patients with Gln70 (His70) and/or Met91. At 8 and 12 weeks, HCV RNA loss rate of patients with rs8099917 genotype TT near IL28B gene was significantly higher than that of patients with non-TT. Multivariate analysis identified substitution of aa 70 and 91 as a predictor of ≥3.0 log fall in HCV RNA level at 24 h (Arg70 and Leu91) and SVR (Arg70), and rs8099917 (TT) as a predictor of HCV RNA loss at 12 weeks and SVR.

CONCLUSIONS

This study identified genetic variation near IL28B gene and aa substitution of the core region as predictors of viral dynamics during triple therapy.

Association of two polymorphisms of the IL28B gene with viral factors and treatment response in 1,518 patients infected with hepatitis C virus

BACKGROUND

Two nucleotide polymorphisms of the interleukin-28B (IL28B) gene, at rs8099917 and rs12979860, influence the response to interferon (IFN)-based therapies in patients infected with hepatitis C virus (HCV) of genotype 1. We aimed to investigate whether these polymorphisms showed complete linkage in Japanese patients.

METHODS

A total of 1,518 Japanese patients infected with HCV were genotyped for the two IL28B loci, and the two sets of genotypes were compared.

RESULTS

TT at rs8099917 and CC at rs12979860 were detected in 77.7 and 76.8%, respectively, of the 1,518 patients and TG/GG and CT/TT were detected in 22.3 and 23.2%. These two sets of IL28B genotype stood in strong linkage disequilibrium (r (2) = 0.98). Discordance between the two IL28B polymorphisms occurred in 16 (1.1%) patients, and 13 (0.9%) of them possessed IFN-sensitive TT at rs8099917 and IFN-resistant CT at rs12979860. Three of these 13 patients had HCV of genotype 1b and had received pegylated-interferon and ribavirin, and none of them gained a sustained virological response. At rs8099917, IFN-resistant TG/GG were more frequent in patients infected with HCV of genotype 1 than in those infected with HCV of genotype 2 [258/1,046 (24.7%) vs. 75/441 (17.0%), p = 0.001]. The response to pegylated-interferon/ribavirin in 279 patients who were infected with HCV-1 and the response to IFN monotherapy in 361 patients who were infected with HCV-1 , was higher in those with TT than in those with TG/GG at rs8099917, as well as being higher in those with CC than in those with CT/TT at rs12979860 (p < 0.001).

CONCLUSIONS

Linkage disequilibrium between two IL28B polymorphisms at rs8099917 and rs12979860 is strong in Japanese HCV patients, but there are some discrepancies between the two sets of genotypes.

A retrospective case-control study of hepatitis C virus infection and oral lichen planus in Japan: association study with mutations in the core and NS5A region of hepatitis C virus

Background

The aims of this study were to assess the prevalence of hepatitis C virus (HCV) infection in Japanese patients with oral lichen planus and identify the impact of amino acid (aa) substitutions in the HCV core region and IFN-sensitivity-determining region (ISDR) of nonstructural protein 5A (NS5A) associated with lichen planus.

Methods

In this retrospective study, 59 patients (group 1-A) with oral lichen planus among 226 consecutive patients who visited our hospital and 85 individuals (group 1-B, controls) with normal oral mucosa were investigated for the presence of liver disease and HCV infection. Risk factors for the presence of oral lichen planus were assessed by logistic regression analysis. We compared aa substitutions in the HCV core region (70 and/or 91) and ISDR of NS5A of 12 patients with oral lichen planus (group 2-A) and 7 patients who did not have oral lichen planus (group 2-B) among patients (high viral loads, genotype 1b) who received interferon (IFN) therapy in group1-A.

Results

The prevalence of anti-HCV and HCV RNA was 67.80% (40/59) and 59.32% (35/59), respectively, in group 1-A and 31.76% (27/85) and 16.47% (14/85), respectively, in group 1-B. The prevalence of anti-HCV (P < 0.0001) and HCV RNA (P < 0.0001) in group 1-A was significantly higher than those in group 1-B. According to multivariate analysis, three factors - positivity for HCV RNA, low albumin level (< 4.0 g/dL), and history of smoking - were associated with the development of oral lichen planus. The adjusted odds ratios for these three factors were 6.58, 3.53 and 2.58, respectively, and each was statistically significant. No significant differences in viral factors, such as aa substitutions in the core region and ISDR of NS5A, were detected between the two groups (groups 2-A and -B).

Conclusion

We observed a high prevalence of HCV infection in patients with oral lichen planus. Longstanding HCV infection, hypoalbuminemia, and smoking were significant risk factors for the presence of oral lichen planus in patients. It is advisable for Japanese patients with lichen planus to be tested for HCV infection during medical examination.

Hepatocellular carcinoma: towards personalized medicine

Over the past several years, the success of genome-wide association studies (GWAS) and pharmacogenomics has gradually begun to enable personalized medicine in some fields. In the field of liver diseases, host genetic factors are now very useful in clinical practice for predicting treatment outcome and adverse reactions for pegylated interferon plus ribavirin combination therapy against chronic hepatitis C virus (HCV) infection. Recently, three virus-related hepatocellular carcinoma (HCC) GWAS were reported from Asia. One study examined hepatitis B virus-related HCC in China, where hepatitis B is very prevalent, and the other two examined HCV-related HCC in Japan. We identified a common variant in the DEPDC5 locus associated with HCV-related HCC, and another group identified an association involving the MICA locus. In this review, we compare the results of these GWAS and earlier candidate gene studies. Further research is needed to determine the role of these single nucleotide polymorphisms on HCC risk, but identification of these markers could make it possible to assess the magnitude of the risk of cancer based on each patient's genetic background. Consideration of the genetic background of the patients will likely play a role in personalized medicine for HCC, and understanding the mechanism underlying the association could suggest novel promising therapeutic targets in the future.

Sequence heterogeneity in NS5A of hepatitis C virus genotypes 2a and 2b and clinical outcome of pegylated-interferon/ribavirin therapy

Pegylated-interferon plus ribavirin (PEG-IFN/RBV) therapy is a current standard treatment for chronic hepatitis C. We previously reported that the viral sequence heterogeneity of part of NS5A, referred to as the IFN/RBV resistance-determining region (IRRDR), and a mutation at position 70 of the core protein of hepatitis C virus genotype 1b (HCV-1b) are significantly correlated with the outcome of PEG-IFN/RBV treatment. Here, we aimed to investigate the impact of viral genetic variations within the NS5A and core regions of other genotypes, HCV-2a and HCV-2b, on PEG-IFN/RBV treatment outcome. Pretreatment sequences of NS5A and core regions were analyzed in 112 patients infected with HCV-2a or HCV-2b, who were treated with PEG-IFN/RBV for 24 weeks and followed up for another 24 weeks. The results demonstrated that HCV-2a isolates with 4 or more mutations in IRRDR (IRRDR[2a]≥4) was significantly associated with rapid virological response at week 4 (RVR) and sustained virological response (SVR). Also, another region of NS5A that corresponds to part of the IFN sensitivity-determining region (ISDR) plus its carboxy-flanking region, which we referred to as ISDR/+C[2a], was significantly associated with SVR in patients infected with HCV-2a. Multivariate analysis revealed that IRRDR[2a]≥4 was the only independent predictive factor for SVR. As for HCV-2b infection, an N-terminal half of IRRDR having two or more mutations (IRRDR[2b]/N≥2) was significantly associated with RVR, but not with SVR. No significant correlation was observed between core protein polymorphism and PEG-IFN/RBV treatment outcome in HCV-2a or HCV-2b infection. Conclusion: The present results suggest that sequence heterogeneity of NS5A of HCV-2a (IRRDR[2a]≥4 and ISDR/+C[2a]), and that of HCV-2b (IRRDR[2b]/N≥2) to a lesser extent, is involved in determining the viral sensitivity to PEG-IFN/RBV therapy.

Safety, pharmacokinetics and resistant variants of telaprevir alone for 12 weeks in hepatitis C virus genotype 1b infection

BACKGROUND

Telaprevir in combination with peginterferon and ribavirin is a promising advancement in chronic hepatitis C treatment. However, the safety, tolerability, pharmacokinetics and antiviral profiles of telaprevir alone beyond 2 weeks have not been studied.

METHODS

In a phase 1b study in Japan, 10 treatment-naïve patients infected with hepatitis C virus genotype 1b with high viral load (>5 log(10) IU/mL) received telaprevir 750 mg every 8 h (q8h) for 12 weeks. We examined the safety, tolerability, pharmacokinetics, hepatitis C virus (HCV) RNA levels and resistant variants of telaprevir.

RESULTS

Neither serious adverse events nor discontinuations of study drug owing to an adverse event occurred. The most common adverse drug reactions were rash (80%) and anaemia (70%). Telaprevir concentration reached its steady state within 2 days after the first administration without abnormal accumulation. Telaprevir alone provided potent antiviral activity: a median log(10) decrease of 2.325 at 16 h and 5.175 on Day 14. During the treatment, HCV RNA levels at the nadir were below the limit of the quantification in seven patients and undetectable in three of 10 patients. Viral breakthrough associated with mainly Ala(156) -substituted variants occurred in eight patients, and only one patient showed end-of-treatment response. The selected variants reverted to the wild-type during the 24-week follow-up period.

CONCLUSION

Telaprevir alone was well tolerated at 750 mg q8h for up to 12 weeks. The safety profile and emergence of resistant variants of genotype 1b under telaprevir monotherapy for 12 weeks will become increasingly important in evaluating an oral combination of telaprevir with other direct-acting antiviral agents.

Serum PAI-1 is a novel predictor for response to pegylated interferon-α-2b plus ribavirin therapy in chronic hepatitis C virus infection

Obesity and insulin resistance have been reported as negative predictors for sustained virological response (SVR) in hepatitis C virus (HCV) genotype 1 infected patients treated with pegylated interferon-α plus ribavirin. They are also known to affect serum levels of several cytokines including adipocytokines. But the association between these cytokines and treatment outcome has not been fully elucidated. We examined pretreatment serum levels of 14 cytokines among 190 patients who were treated with pegylated interferon-α-2b plus ribavirin for chronic HCV-1b infection with high viral load (≥ 5 log IU/mL) and analyzed their contribution to treatment response. Plasminogen activator inhibitor-1 (PAI-1), vascular endothelial growth factor, and 11 clinical factors showed significant association with SVR in univariate logistic regression analysis. Four significant factors in multivariate analysis; serum PAI-1 (odds ratio [OR] = 15.42), body mass index (OR = 4.56), rs8099917 (OR = 4.95) and fibrosis stage (OR = 5.18) were identified as independent predictors. We constructed a simple and minimally invasive prediction score for SVR based on the presence of these factors except for fibrosis stage. The accuracy of this score was 73%, and was confirmed using an independent validation cohort consisting of 31 patients (68%). The strongest correlation was between PAI-1 level and platelet count (r = 0.38, P = 1.8 × 10(-7)), and PAI-1 level was inversely correlated with fibrosis stage. Serum PAI-1 is a novel predictor for the response to combination therapy against chronic HCV-1b infection and may be associated with liver fibrosis.

Dynamics of regulatory T cells and plasmacytoid dendritic cells as immune markers for virological response in pegylated interferon-α and ribavirin therapy for chronic hepatitis C patients

BACKGROUND

For the treatment of chronic hepatitis C, a combination of pegylated interferon-α (PEG-IFNα) and ribavirin has been widely used as a standard of care. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. Our aim was to elucidate whether or not the frequency or function of blood cells is related to the outcome of the therapy.

METHODS

Sixty-seven chronic hepatitis C patients with high viral load of HCV genotype 1 infection who underwent 48 weeks of PEG-IFNα2b and ribavirin therapy were examined. During the treatment, frequencies of myeloid or plasmacytoid dendritic cells, Th1, Th2 cells, NK cells, and regulatory T cells were phenotypically determined.

RESULTS

Among the patients enrolled, 29 showed a sustained virological response (SVR), 18 a transient response (TR) and 17 no response (NR). The clinical and immunological markers were compared between the SVR and non-SVR patients, including TR and NR. Based on clinical, histological, immunological parameters, and cumulative dosage of PEG-IFNα2b and ribavirin, multivariate analyses revealed that higher platelet counts and higher regulatory T cell frequency at week 12 are indicative of SVR. Even in patients who attained complete early virological response at week 12, multivariate analyses disclosed that higher platelet counts and higher plasmacytoid dendritic cell frequency are indicative of SVR.

CONCLUSIONS

In PEG-IFNα and ribavirin combination therapy for chronic hepatitis C patients, the increments of regulatory T cells and plasmacytoid dendritic cell frequency are independently related to favorable virological response to the therapy.

Interleukin-28B gene polymorphisms: a new beginning of personalized treatment of hepatitis C

It is well known that genetic diversity of individual hosts plays a significant role in the treatment of patients with chronic hepatitis C. From August 2009 to January 2010, four independent genome-wide association studies (GWAS) around the world have demonstrated that interleukin-28B (IL28B) gene polymorphisms are associated with antiviral treatment response to pegylated interferon and ribavirin combination therapy (PEG-IFN/RBV). Two single nucleotide polymorphisms (SNPs), rs8099917 and rs12979860, in the IL28B gene are most strongly associated with sustained virological response (SVR). This review aims to describe the association of IL28B genotypes with treatment response, natural clearance of HCV, molecular epidemiology of HCV infection and some drug side effects. Current observations give us a hint that the era of personalized therapy based on IL28B genotypes may come in the near future.