Pre-treatment prediction of response to pegylated-interferon plus ribavirin for chronic hepatitis C using genetic polymorphism in IL28B and viral factors

Estimation of two real-time RT-PCR assays for quantitation of hepatitis C virus RNA during PEG-IFN plus ribavirin therapy by HCV genotypes and IL28B genotype

Hepatitis C virus (HCV) RNA values measured with two real-time PCR methods (Cobas Ampliprep/Cobas TaqMan, CAP/CTM, and the Abbott real-time PCR test, ART) vary among patients with genotype 1. We investigated HCV RNA values measured by two real-time PCR assays during pegylated interferon plus ribavirin (PEG-IFN/RBV) therapy. We evaluated 185 cases of chronic hepatitis C patients, among which 97 patients received the PEG-IFN/RBV therapy. HCV RNA values of CAP/CTM for genotype 1 were significantly higher than those of ART (p < 0.05) The difference in HCV RNA values (CAP/CTM minus ART) of genotype 1 was significantly higher than those in genotype 2 (p < 0.0001). The positive rate (>0) of the difference of HCV RNA values in genotype 1 was 100 % (55/55), which was significantly higher than the 78.6 % (33/42) of genotype 2 (p < 0.001). There was no difference between TT and TG/GG genotype groups in terms of difference of HCV RNA values (CAP/CTM minus ART). After PEG-IFN/RBV therapy was administered, reduction of HCV measurements was observed from day 1 for both assays regardless of genotype. The HCV value of CAP/CTM during PEG-IFN/RBV therapy was consistently higher than the value of ART, although the difference in these two values gradually became smaller during the course of therapy, and eventually no significant difference was observed near the detection level. No correlation was observed between the sustained virological response (SVR) rate and the difference between the CAP/CTM HCV values and the ART HCV value before treatment.

Association study of IL28B: rs12979860 and rs8099917 polymorphisms with SVR in patients infected with chronic HCV genotype 1 to PEG-INF/RBV therapy using systematic meta-analysis

Recently, genome-wide associated studies (GWAS) have identified that host genetics IL28B SNPs rs12979860 and rs8099917 were significantly associated with SVR in patients infected with chronic HCV genotype 1 to PEG-INF/RBV therapy. Results from these studies remain conflicting. We conducted this meta-analysis to estimate the overall association of SVR with rs12979860 and rs8099917. We searched the PubMed, Embase, Scholar Google, ISI Web of Knowledge, and Chinese National Knowledge Infrastructure (CNKI) databases for all articles before July 30, 2012. The odds ratio (OR) corresponding to the 95% confidence interval (CI) was used to assess the association. The statistical heterogeneity among studies was assessed with the I(2) statistics. Begg's test and Egger's test were performed to evaluate the publication bias. Eventually, twenty studies were selected for the meta-analysis. The IL-28B SNPs rs12979860 genotype CC and rs8099917 genotype TT significantly positive associated with SVR in patients infected chronic HCV genotype 1 to PEG-INF/RBV therapy (OR=4.473, 95% CI=3.814-5.246, OR=5.171, 95% CI=4.372-6.117 respectively). The results suggested that rs12979860 genotype CC and rs8099917 genotype TT could be used as independent predictors of the HCV-1 infected patients.

Meta-analysis: implications of interleukin-28B polymorphisms in spontaneous and treatment-related clearance for patients with hepatitis C

BACKGROUND

Since 2009, several studies have identified single-nucleotide polymorphisms (SNPs) near the gene encoding for interleukin (IL)-28 (IL28B) that are strongly associated with spontaneous and treatment-induced hepatitis C virus (HCV) clearance. Because this large amount of data includes some inconsistencies, we consider assessment of the global estimate for each SNP to be essential.

METHODS

Relevant studies assessing IL28B polymorphisms associated with sustained virologic response (SVR) and spontaneous clearance (SC) were identified from a literature search of PubMed up to 9 July, 2012. Studies were eligible studies if they included patients infected with HCV or HCV/HIV, or assessed any SNP located within or near the IL28B gene, SVR data available under standard treatment, and/or SC data in patients with acute HCV infection. Pooled odds ratios were estimated by fixed or random effects models when appropriate. Variables such as HCV genotype, ethnicity, and type of co-infection were studied.

RESULTS

Of 282 screened studies, 67 were selected for SVR and 10 for SC. In total, 20,163 patients were studied for SVR and 3,554 for SC. For SVR, we found that all SNPs showed strong associations in patients with HCV genotypes 1 and 4, whereas the pooled ORs were almost three times lower for genotypes 2 and 3 (rs12979860 and rs8099917). Regarding ethnicity, the SNP most associated with SVR was rs12979860 in white patients, whereas in East Asians it seemed to be rs8099917. The most studied SNP (rs12979860) showed similar results for patients co-infected with HCV/HIV, as for those infected with HCV only. Finally, rs12979860 and rs8099917 both appeared to be associated with SC.

CONCLUSIONS

IL28B polymorphisms influence both the outcome of interferon treatment and the natural clearance of HCV. However we did not identify a universal predictor SNP, as the best genetic markers differed depending on patient ethnicity, genotype, and type of infection. Nevertheless, our results may be useful for more precise treatment decision-making.

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.

Combination of fluvastatin with pegylated interferon/ribavirin therapy reduces viral relapse in chronic hepatitis C infected with HCV genotype 1b

BACKGROUND AND AIM

Although the anti-hepatitis C virus (HCV) effect of statins in vitro and clinical efficacy of fluvastatin combined with Pegylated interferon (PEG-IFN)/ribavirin therapy for chronic hepatitis C (CHC) have been reported, the details of clinical presentation are largely unknown. We focused on viral relapse that influences treatment outcome, and performed a post-hoc analysis by using data from a randomized controlled trial.

METHODS

Thirty-four patients in the fluvastatin group and 33 patients in the non-fluvastatin group who achieved virological response (complete early virological response [cEVR] or late virological response [LVR]) with PEG-IFN/ribavirin therapy were subjected to this analysis. Factors contributing to viral relapse were identified by using multiple logistic regression analysis.

RESULTS

Relapse rate in patients with cEVR was significantly lower in the fluvastatin group (2 of 23, 8.7%) than in the non-fluvastatin group (9 of 26, 34.6%; P = 0.042). The use of fluvastatin decreased relapse rate in patients with LVR (27.3% vs 57.1%), though not significantly. Overall, relapse rate was significantly lower in the fluvastatin group (14.7%; 5 of 34) than in the non-fluvastatin group (39.4%; 13 of 33; P = 0.027). Multivariate analysis identified absence of fluvastatin (P = 0.027, odds ratio [OR] = 3.98, 95% confidence interval [CI] = 1.05-15.11) and low total ribavirin dose (P = 0.002, OR = 2.41, 95% CI = 1.38-4.19) as independent factors contributing to relapse.

CONCLUSION

The concomitant addition of fluvastatin significantly suppressed viral relapse, resulting in the improvement of sustained virological response rate, in PEG-IFN/ribavirin therapy for CHC patients with HCV genotype 1b and high viral load.

Progress in research of genotypes of hepatitis C virus

Hepatitis C virus (HCV), belonging to the Flaviviridae family, is divided into six genotypes and different subtypes. There are four nomenclatures for HCV, of which the nomenclature system proposed by Simmonds et al. is widely applied overseas in recent years. HCV genotypes have obvious geographical variation and show significant epidemiological differences. Five methods are currently available for genotyping HCV, and each has its own advantages and disadvantages. HCV genotypes closely correlate with the severity, course, progression, treatment, and outcome of hepatitis C. The therapeutic effect for different HCV genotypes varies, and IL-28B polymorphism is a predictor of sustained virological response to treatment among various HCV genotypes. The diversity of HCV genotypes brings certain difficulty to vaccine development. Some success has been achieved in the development of HCV vaccine in animals. The main purpose of the present article is to review the recent progress in research of genotypes of HCV in terms of genotyping methods, associations between genotypes and epidemiological significance, severity of disease, and antiviral treatment response, and vaccine development.

A single nucleotide polymorphism in IL28B affects viral evolution of hepatitis C quasispecies after pegylated interferon and ribavirin therapy

Interleukin-28B (IL28B) polymorphisms are associated with viral response to peginterferon and ribavirin (RBV) in chronic hepatitis C (HCV). Their recognition represents a breakthrough in the understanding of the role of the host in viral eradication. How these polymorphisms determine viral eradication is unknown. The IL-28B variants are hypothesized to have a differential impact on HCV quasispecies evolution during treatment with pegylated interferon (PEG-IFN) and RBV. In this study, HCV RNA levels were measured at early time points in 33 naïve genotype 1 hepatitis C patients and clonal analysis of the entire NS5A region was performed on sera from baseline and Day 7. Site rs12979860 polymorphisms were determined by direct sequencing of PCR products and classified into CC, CT, and TT and were identified in 13, 11, and 9 patients, respectively. The CC polymorphism more commonly was seen in Whites versus Blacks [12/21 (57%) vs. 1/12 (8%), P = 0.009] and HIV-infected versus mono-infected [13/25 (52%) vs. 0/8 (0%), P = 0.009]. Patients with CC and non-CC had similar baseline viral loads. More patients with the CC polymorphism had amino acid substitutions in NS5A compared to non-CC patients. Despite similar baseline viral diversity, by Day 7, significantly more patients with CC had higher non-synonymous substitution values compared to non-CC (P = 0.02). Chronic hepatitis C patients with the CC IL28B polymorphism have a higher number of amino acid substitutions in the NS5A region and early viral evolution due to greater interferon induced selective pressure during this critical period of treatment.

Host genetic variants in the pathogenesis of hepatitis C

Direct-acting antiviral drugs (DAAs) are currently replacing antiviral therapy for Hepatitis C infection. Treatment related side effects are even worse and the emergence of resistant viruses must be avoided because of the direct-antiviral action. Altogether it remains a challenge to take treatment decisions in a clinical setting with cost restrictions. Genetic host factors are hereby essential to implement an individualized treatment concept. In recent years results on different genetic variants have been published with a strong association with therapy response, fibrosis and treatment-related side effects. Polymorphisms of the IL28B gene were identified as accurate predictors for therapy response and spontaneous clearance of HCV infection and are already used for diagnostic decisions. For RBV-induced side effects, such as hemolytic anemia, associations to genetic variants of inosine triphosphatase (ITPA) were described and different SLC28 transporters for RBV-uptake have been successfully analyzed. Fibrosis progression has been associated with variants of Vitamin D receptor (VDR) and ABCB11 (bile salt export pump). Cirrhotic patients especially have a high treatment risk and low therapy response, so that personalized antiviral treatment is mandatory. This review focuses on different host genetic variants in the pathogenesis of Hepatitis C at the beginning of a new area of treatment.

Novel biosensor-based microarray assay for detecting rs8099917 and rs12979860 genotypes

AIM

To evaluate a novel biosensor-based microarray (BBM) assay for detecting rs12979860 and rs8099917 genotypes.

METHODS

Four probes specific for rs8099917C/T or rs12979860G/T detection and three sets of quality control probes were designed, constructed and arrayed on an optical biosensor to develop a microarray assay. Two sets of primers were used in a one tube polymerase chain reaction (PCR) system to amplify two target fragments simultaneously. The biosensor microarray contained probes that had been sequenced to confirm that they included the rs8099917C/T or rs12979860G/T alleles of interest and could serve as the specific assay standards. In addition to rehybridization of four probes of known sequence, a total of 40 clinical samples collected from hepatitis C seropositive patients were also tested. The target fragments of all 40 samples were amplified in a 50 μL PCR system. Ten μL of each amplicon was tested by BBM assay, and another 40 μL was used for sequencing. The agreement of the results obtained by the two methods was tested statistically using the kappa coefficient. The sensitivity of the BBM assay was evaluated using serial dilutions of ten clinical blood samples containing 10(3)-10(4) white cells/μL.

RESULTS

As shown by polyacrylamide gel electrophoresis, two target segments of the interleukin 28B-associated polymorphisms (SNPs) were successfully amplified in the one-tube PCR system. The lengths of the two amplified fragments were consistent with the known length of the target sequences, 137 and 159 bps. After hybridization of the PCR amplicons with the probes located on the BBM array, the signals of each allele of both the rs8099917 SNPs and rs12979860 SNPs were observed simultaneously and were clearly visible by the unaided eye. The signals were distinct from each other, could be interpreted visually, and accurately recorded using an ordinary digital camera. To evaluate the specificity of the assay, both the plasmids and clinical samples were applied to the microarray. First, 30 PCR amplicons of the various SNP alleles were hybridized on the BBM microarray. Full agreement between plasmids and the BBM assay was observed, with 30/30 correct matches (100%). The kappa value for the BBM assay with plasmids was 1.00 (P < 0.05). For the 40 clinical blood samples, the BBM assay hybridization and direct sequencing results were compared for each amplicon. For patient blood samples, agreement was 28/28 for rs8099917T/T, 9/11 for rs8099917T/G, 1/1 for rs8099917G/G, 24/24 for rs12979860C/C, 11/14 for rs12979860C/T, and 2/2 for rs12979860T/T. Only five clinical samples of amplicon assay and direct sequencing results were discordant and heterozygotes: 2/11 rs8099917T/G and 3/14 rs12979860C/T. The agreement of outcomes between BBM assay and direct sequencing for the detection of rs8099917 and rs12979860 was 95% and 92.5%, respectively; and the corresponding kappa values were 0.88 and 0.85 (A kappa value > 0.75 was defined as substantial agreement). The BBM assay and sequencing had similar specificities for detection and identification of the two SNPs and their alleles. The sensitivity evaluation showed that the BBM assay could detect and identify SNP sequences present in blood samples containing as few as 10(2) white blood cells/μL.

CONCLUSION

This biosensor microarray assay was highly specific, sensitive, rapid and easy to perform. It is compatible with clinical practice for detection of rs8099917 and rs12979860.

Comprehensive analysis for viral elements and interleukin-28B polymorphisms in response to pegylated interferon plus ribavirin therapy in hepatitis C virus 1B infection

To comprehensively characterize the contribution of virological factors as well as interleukin-28B (IL28B) single-nucleotide polymorphisms (SNPs) in determining treatment responses in pegylated-interferon plus ribavirin (Peg-IFN/RBV) therapy for chronic hepatitis C virus (HCV)-1b infection, we undertook a retrospective cohort analysis for the pretreatment dominant complete HCV open reading frame (ORF) amino-acid (aa) sequence study in 103 consecutive HCV-1b Japanese patients. The dominant HCV sequences classified by the response were subjected to systematic sliding-window comparison analysis to characterize response-specific viral sequences, along with IL28B SNP analyses (rs8099917). In each comparison of the patients between with and without rapid viral response (RVR), nonearly viral response (nEVR), sustained virological response (SVR), or relapse, the following regions were extracted as most significantly associated with the different responses respectively: nonstructural protein 5A (NS5A) aa.2224-2248 (P = 1.2E-07); core aa.70 (P = 4E-04); NS5A aa.2340-2382 (P = 7.0E-08); and NS5A aa.2360-2377 (P = 1.1E-05). Those NS5A regions nearly coincided with the interferon (IFN) sensitivity-determining region (NS5A aa.2209-2248) and the IFN/RBV resistance-determining region (NS5A aa.2339-2379). In a multivariate analysis, the IL28B SNP (odds ratio [OR] = 16.8; P = 0.009) and NS5A aa.2340-2382 (OR = 13.8; P = 0.0003) were extracted as the two most-significant independent variables contributing to the final outcome.

CONCLUSION

In Peg-IFN/RBV therapy, polymorphisms in IL28B, NS5A aa.2224-2248, core aa.70, and, most important, NS5A aa.2340-2382 have a tremendous influence on treatment response in association with viral kinetics, resulting in significantly different outcomes in chronic HCV-1b infection.

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

AIM

  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.

METHODS

  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.

RESULTS

  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.

CONCLUSION

  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.

Interleukin-28B polymorphisms on the SVR in the treatment of naïve chronic hepatitis C with pegylated interferon-α plus ribavirin: a meta-analysis

There are accurate but inconclusive data on the association between single nucleotide polymorphisms (SNPs) of interleukin (IL)-28B and sustained virological response (SVR) in chronic hepatitis C (CHC). This meta-analysis aimed to derive a more precise estimation of the effects of IL-28B SNPs locus (rs12979860 and rs8099917) on SVR in naïve CHC patients receiving pegylated interferon alpha (PEG-IFN-α) plus ribavirin. Literature search was conducted up to June, 2011, in PubMed, EMBASE and Cochrane Database of Systematic Reviews. A total of 36 studies involving 10912 cases with CHC receiving PEG-IFN-α plus ribavirin met the inclusion criteria. Analyses were stratified either by ethnicity or genotype of hepatitis C virus. In genotype 1/4 patients, rs12979860 CC was associated with high SVR in CHC patients (Caucasian: odds ratio (OR), 4.567; 95% confidence interval (CI), 3.826-5.452; Asian: OR, 4.033; 95%CI, 3.050-5.333; African American: OR, 4.297; 95%CI, 2.168-8.515; Hispanics: OR, 4.350; 95%CI, 2.817-6.717) but had no effect in genotype 2/3. In Caucasian (genotype 1/4: OR, 2.542; 95%CI, 2.108-3.065; genotype 2/3: OR, 1.363; 95%CI, 1.020-1.820) and Asian (genotype 1/4: OR, 5.214; 95%CI, 3.694-7.360; genotype 2/3: OR, 1.785; 95%CI, 1.095-2.910), rs8099917 TT was associated with high SVR in both genotype 1/4 and 2/3. Meta-regression showed that in Caucasians with CHC genotype 1/4, gender male might contribute to the effect of rs12979860 on SVR but advanced fibrosis might weaken this effect. Furthermore, in Asians with CHC genotype 1/4, high baseline viral load and advanced fibrosis might also undermine the effect of rs8099917 on SVR. This meta-analysis suggested that IL-28B rs12979860 CC and rs8099917 TT were associated with high SVR rate in CHC genotype 1/4. In CHC genotype 2/3, rs8099917 TT carriers also had higher SVR.

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.

Fish to meat intake ratio and cooking oils are associated with hepatitis C virus carriers with persistently normal alanine aminotransferase levels

AIM

  Dietary habits are involved in the development of chronic inflammation; however, the impact of dietary profiles of hepatitis C virus carriers with persistently normal alanine transaminase levels (HCV-PNALT) remains unclear. The decision-tree algorithm is a data-mining statistical technique, which uncovers meaningful profiles of factors from a data collection. We aimed to investigate dietary profiles associated with HCV-PNALT using a decision-tree algorithm.

METHODS

  Twenty-seven HCV-PNALT and 41 patients with chronic hepatitis C were enrolled in this study. Dietary habit was assessed using a validated semiquantitative food frequency questionnaire. A decision-tree algorithm was created by dietary variables, and was evaluated by area under the receiver operating characteristic curve analysis (AUROC).

RESULTS

  In multivariate analysis, fish to meat ratio, dairy product and cooking oils were identified as independent variables associated with HCV-PNALT. The decision-tree algorithm was created with two variables: a fish to meat ratio and cooking oils/ideal bodyweight. When subjects showed a fish to meat ratio of 1.24 or more, 68.8% of the subjects were HCV-PNALT. On the other hand, 11.5% of the subjects were HCV-PNALT when subjects showed a fish to meat ratio of less than 1.24 and cooking oil/ideal bodyweight of less than 0.23 g/kg. The difference in the proportion of HCV-PNALT between these groups are significant (odds ratio 16.87, 95% CI 3.40-83.67, P = 0.0005). Fivefold cross-validation of the decision-tree algorithm showed an AUROC of 0.6947 (95% CI 0.5656-0.8238, P = 0.0067).

CONCLUSION

  The decision-tree algorithm disclosed that fish to meat ratio and cooking oil/ideal bodyweight were associated with HCV-PNALT.

Test of IL28B polymorphisms in chronic hepatitis C patients treated with PegIFN and ribavirin depends on HCV genotypes: results from a meta-analysis

BACKGROUND

Many studies have been published on the association between single nucleotide polymorphisms (SNP) near the IL28B gene and response to the combined treatments of pegylated-interferon (PegIFN) and ribavirin (RBV) in chronic HCV-infected patients, but without identical conclusions. The aim of this study was to assess impact of the IL28B polymorphisms on the effect of HCV standard treatment using meta-analysis based method.

METHODS

Association studies between polymorphisms of rs12979860 or rs8099917 and response to PegIFN/RBV treatment in chronic HCV patients were retrieved from PubMed. Data of qualified studies on sustained virological response (SVR) in different genotypes were extracted and analyzed using meta-analysis method in Stata 10 software.

RESULTS

Thirty-four papers, containing 46 independent studies, were included in the analysis. In the HCV G1/4 patients without treatment history, individuals carrying rs12979860 CC genotype were more likely to achieve SVR (OR 3.97, 95%CI 3.29-4.80) compared to those carrying CT/TT genotypes. Similar results were observed in the HCV G1/4 patients with unsuccessful or unknown treatment history (OR 3.76, 95%CI 2.67-5.28) or in the patients co-infected with human immunodeficiency virus (OR 5.20, 95%CI 3.04-8.90). However, associations could not be observed in HCV G2/3 patients. For rs8099917, similar results were obtained for genotype TT compared to genotypes TG/GG, indicating that TT genotype was significantly associated with better treatment response in patients infected with genotype 1 or 4 HCV, but not genotype 2 or 3 HCV.

CONCLUSION

Polymorphisms of rs12979860 and rs8099917 near IL28B only associate with the treatment response to PegIFN/RBV in patients infected with HCV genotype 1 or 4 but not with genotype 2 or 3, irrespective of the previous treatment history or HIV co-infected status. Therefore, identification of IL28B genotypes is necessary only in patients infected with relatively difficult-to-treat genotype 1 or 4 HCV.

Branch retinal artery occlusion and central retinal vein occlusion associated with pegylated interferon plus ribavirin combination therapy for chronic hepatitis C

A 62-year-old male treated with pegylated interferon α-2b plus ribavirin for chronic hepatitis C complained of sudden painless decreased visual acuity. This patient was diagnosed as having simultaneous occlusions of the branch retinal artery and central retinal vein, although he had no history of major risk factors for retinal vessel (artery and vein) occlusion. Unfortunately, visual acuity did not completely recover. Furthermore, the patient was heterozygous for interleukin (IL) 28B genetic polymorphisms. The etiology of interferon-associated retinal vessel occlusion is not yet clear. However, a review based on previous case reports suggested that some factors including ribavirin might act as a risk or cause of retinal vessel occlusion.

The reduced predictive value of interleukin 28b gene polymorphisms in a cohort of patients with thyroiditis developed during antiviral therapy for chronic hepatitis C: a preliminary study

BACKGROUND

Single nucleotide polymorphism in the interleukin28B (IL28B) gene was recently shown to be associated with a significant increase in response to interferon-α and ribavirin treatment in patients with chronic hepatitis C. Similarly, thyroid disease (TD) occurring during treatment confer an improved sustained virologic response (SVR).

OBJECTIVES

To determine the role of IL28B genotypes in a cohort of hepatitis C patients who develop TD during treatment and its relationship to SVR.

PATIENTS AND METHODS

IL28B gene profiles including rs12979860, rs12980275 and rs 8099917 and their genotypes were determined in a cohort of 23 hepatitis C patients who developed TD during treatment and their relationship to SVR.

RESULTS

Out of 23 studies cases, 19 has one or more favorable genotypes, of which 15 (78.9%) achieved SVR. Eleven has all three unfavorable genotypes and yet achieved 72.7 % SVR. The presence of more than one favorable genotype only correctly predicts SVR vs. non- SVR in ~50 % of cases, i.e. by chance.

CONCLUSIONS

Despite the small number of subjects, the presence of one or more unfavorable IL28B genotype does not portend a poor SVR prognostic outcome. This suggests that TD in this clinical context may be a critical factor in the achievement of SVR, probably above that of the genetic predisposition.

Meta-analysis: IL-28B genotype and sustained viral clearance in HCV genotype 1 patients

BACKGROUND

Polymorphisms in the IL-28B region are a strong predictor of sustained virologic response (SVR) in individual studies of HCV genotype 1 patients receiving peginterferon (pegIFN) and ribavirin.

AIM

To obtain a pooled odds ratio (OR) of SVR in patients of varying race with the favourable IL-28B genotype compared to those with the unfavourable genotype.

METHODS

A literature search was conducted using online databases and a review of conference abstracts. A random effects meta-analysis was performed and study heterogeneity and publication bias were assessed.

RESULTS

There were 21 individual studies of HCV genotype 1 patients of varying ethnicity treated with pegIFN and ribavirin. The pooled prevalence of the favourable IL-28B genotype varied by race (73% vs. 41% vs. 13% in 2612 Asians, 3110 Caucasians and 452 African-Americans, respectively, P < 0.001). However, the strength of association of the IL-28B genotype with SVR was similar in all three racial groups (Caucasians: odds ratio (OR) 3.88, 2.75-5.49, African-Americans: OR 4.63, 2.52-8.50 and Asians OR 5.66, 3.99-8.02, all P < 0.001). The IL-28B genotype was also associated with SVR in 263 HIV/HCV co-infected Caucasians (OR 5.49, 3.02-9.96, P < 0.001). Study quality score and anti-viral treatment regimen did not impact the strength of the association in patient subgroups nor in the pooled population.

CONCLUSIONS

IL-28B genotype is significantly associated with SVR in HCV genotype 1 patients of varying race, as well as in HIV co-infected patients, receiving pegIFN and ribavirin. IL-28B testing in conjunction with other pre-treatment parameters may prove useful in counselling HCV patients.

Genetics of IL28B and HCV--response to infection and treatment

The IL28B locus attracted the attention of HCV researchers after a series of genome-wide association studies independently identified a strong association between common IL28B polymorphisms and the outcome of PEG-IFN-α plus ribavirin combination therapy in patients chronically infected with HCV genotype 1. This association was subsequently replicated for other HCV genotypes and has been linked to spontaneous eradication of HCV, development of steatosis and biochemical changes (such as altered levels of γ-glutamyl transpeptidase and LDL). Despite the introduction of direct-acting antiviral drugs, IL28B genetics are likely to play a part in patient selection and treatment decisions-moving towards a personalized approach to therapy. In HCV-infected patients with the so-called favourable IL28B genotype (rs12979860 CC; associated with better treatment response), hepatic expression levels of IL28B and interferon-stimulated genes seem to be reduced at baseline, but are induced more strongly after IFN-α administration, perhaps resulting in more effective elimination of the virus. Clarification of the mechanisms underlying these biological phenomena will lead to improved understanding of the antiviral effects of IFN-λ and, ideally, to the development of better therapies against HCV infection. This Review summarizes current understanding of the role of IL28B in HCV infection and response to therapy.

Relation of IL28B gene polymorphism with biochemical and histological features in hepatitis C virus-induced liver disease

BACKGROUND/AIMS

Polymorphism at the IL28B gene may modify the course of hepatitis C virus (HCV) chronic infection. Our aim was to study the influence of IL28B rs12979860 gene polymorphism on the biochemistry and pathology of HCV-induced disease in the clinical course from mild chronic hepatitis C to hepatocellular carcinoma.

METHODS

We have determined the rs12979860 single nucleotide polymorphism (SNP) upstream IL28B gene in two groups of patients with HCV-induced chronic liver disease: 1) 268 patients (159 men) with biopsy-proven chronic hepatitis C, to analyse its relation with biochemical, virological and histological features; and 2) 134 patients (97 men) with HCV-related hepatocellular carcinoma. The distribution of the analysed SNP in hepatocellular carcinoma patients was compared with that found in untreated chronic hepatitis C patients. All patients were white and most were Spaniards.

RESULTS

In multivariate analysis ALT values were higher (P = 0.001) and GGT values were lower (P<0.001) in chronic hepatitis C patients homozygotes for the major rs12979860C allele as compared with carriers of the mutated rs12979860T allele. Steatosis was more frequent (Odds ratio = 1.764, 95% C.I. 1.053-2.955) and severe (P = 0.026) in carriers of the rs12979860T allele. No relation was found between the analysed SNP and METAVIR scores for necroinflammation and fibrosis, and there were no differences in the distribution of the analysed SNP between hepatocellular carcinoma and untreated chronic hepatitis C patients.

CONCLUSION

The IL28B rs12979860 polymorphism correlates with the biochemical activity and the presence and severity of liver steatosis in chronic hepatitis C.

Lymphotropic hepatitis C virus has an interferon-resistant phenotype

Hepatitis C virus (HCV) infects and associates with B cells, leading to abnormal B-cell activation and development of lymphoproliferative and autoimmune disorders. This immune perturbation may in turn be associated with the resistance of HCV against the host immune system. The objective of this study was to analyse the effects of HCV infection of B cells on the efficacy of interferon (IFN)-based therapy. The study enrolled 102 patients with chronic hepatitis C who were treated with pegylated IFN plus ribavirin. HCV RNA titres in B cells were compared in patients with rapid viral responder (RVR) vs non-RVR, sustained viral responder (SVR) vs non-SVR and null viral responder (NVR) vs VR. The levels of HCV RNA in B cells were significantly higher in non-RVR, non-SVR and NVR groups. Association between the therapy outcome and the positive B-cell HCV RNA was also investigated in relation to other known viral and host factors. Multivariable analyses showed that the positive B-cell HCV RNA and the minor single-nucleotide polymorphism near the IL28B gene (rs8099917) were independent factors associated with NVR in patients infected with HCV genotype 1. When these two factors were combined, the sensitivity, specificity, positive and negative predictive values for NVR were 92.3%, 98.2%, 92.3% and 98.2%, respectively. Genotype 1 and the presence of one or no mutations in the IFN-sensitivity determining region were associated with higher levels of B-cell HCV RNA. B-cell-tropic HCV appears to have an IFN-resistant phenotype. B-cell HCV RNA positivity is a predictive factor for resistance to IFN-based therapy.

Prevalence of hepatitis C virus genotype 1a in Japan and correlation of mutations in the NS5A region and single-nucleotide polymorphism of interleukin-28B with the response to combination therapy with pegylated-interferon-alpha 2b and ribavirin

Hepatitis C virus (HCV) genotype 1a is rare in Japanese patients and the clinical characteristics of this genotype remain unclear. The interferon (IFN) sensitivity-determining region (ISDR) and single-nucleotide polymorphisms (SNPs) of interleukin-28B (IL28B) among patients with HCV genotype 1b are associated with IFN response, but associations among patients with genotype 1a are largely unknown. This study investigated the clinical characteristics of genotype 1a and examined whether genomic heterogeneity of the ISDR and SNPs of IL28B among patients with HCV genotype 1a affects response to combination therapy with pegylated-IFN-α2b and ribavirin. Subjects comprised 977 patients infected with HCV genotype 1, including 574 men and 412 women (mean age, 55.2 ± 10.6 years). HCV was genotyped by direct sequencing of the 5'-untranslated region and/or core regions and confirmed by direct sequencing of the NS5A region. HCV genotypes 1a (n = 32) and 1b (n = 945) were detected. Twenty-three (71.9%) of the 32 patients with genotype 1a were patients with hemophilia who had received imported clotting factors. Prevalence of genotype 1a after excluding patients with hemophilia was thus 0.9%. Of the 23 patients with genotype 1a who completed IFN therapy, 11 (47.8%) were defined as achieving sustained virological response. Factors related to sustained virological response by univariate analysis were IL28B and ISDR. In conclusion, HCV genotype 1a is rare in Japan. The presence of IL28B genotype TT, and more than two mutations, in the ISDR are associated with a good response to IFN therapy in patients with HCV genotype 1a.

UK consensus guidelines for the use of the protease inhibitors boceprevir and telaprevir in genotype 1 chronic hepatitis C infected patients

BACKGROUND

The nonstructural 3 serine protease inhibitors (PIs), boceprevir and telaprevir, represent the first in a new generation of directly acting antivirals against genotype 1 hepatitis C (HCV) infection. When used in combination with pegylated interferon and ribavirin, these drugs greatly improve sustained virological response rates in both treatment-naïve patients and patients who have had previous virological failure on treatment. However, the addition of these new agents will increase the complexity of therapeutic regimens, the rates of side-effects and costs.

AIMS

To review concisely the current evidence and to suggest current best practice, for the use of telaprevir and boceprevir in the management of chronic genotype 1 HCV infection.

METHODS

These guidelines for the use of boceprevir and telaprevir have been formulated following extensive review of the current literature, are based on the consensus opinion of a panel of national experts, and have been openly discussed and debated at a national meeting of HCV care providers.

RESULTS

We have made recommendations on a number of the key practical issues facing HCV care providers: (i) Which patients to treat?; (ii) Standards for the provision of care; (iii) Pre-treatment considerations; (iv) Which treatment regimens to use?; (v) Stopping rules; and (vi) Management of adverse effects. Finally, we have produced suggested algorithms for the assessment and treatment of these patients.

CONCLUSIONS

These UK Consensus guidelines indicate the current best practice for the use of boceprevir and telaprevir in the management of genotype 1 chronic HCV infection.

Data mining model using simple and readily available factors could identify patients at high risk for hepatocellular carcinoma in chronic hepatitis C

BACKGROUND & AIMS

Assessment of the risk of hepatocellular carcinoma (HCC) development is essential for formulating personalized surveillance or antiviral treatment plan for chronic hepatitis C. We aimed to build a simple model for the identification of patients at high risk of developing HCC.

METHODS

Chronic hepatitis C patients followed for at least 5 years (n=1003) were analyzed by data mining to build a predictive model for HCC development. The model was externally validated using a cohort of 1072 patients (472 with sustained virological response (SVR) and 600 with nonSVR to PEG-interferon plus ribavirin therapy).

RESULTS

On the basis of factors such as age, platelet, albumin, and aspartate aminotransferase, the HCC risk prediction model identified subgroups with high-, intermediate-, and low-risk of HCC with a 5-year HCC development rate of 20.9%, 6.3-7.3%, and 0-1.5%, respectively. The reproducibility of the model was confirmed through external validation (r(2)=0.981). The 10-year HCC development rate was also significantly higher in the high-and intermediate-risk group than in the low-risk group (24.5% vs. 4.8%; p<0.0001). In the high-and intermediate-risk group, the incidence of HCC development was significantly reduced in patients with SVR compared to those with nonSVR (5-year rate, 9.5% vs. 4.5%; p=0.040).

CONCLUSIONS

The HCC risk prediction model uses simple and readily available factors and identifies patients at a high risk of HCC development. The model allows physicians to identify patients requiring HCC surveillance and those who benefit from IFN therapy to prevent HCC.

Host genomics and HCV treatment response

In 2009, an association between the interleukin-28B (IL28B) polymorphism and treatment outcome for genotype 1 (G1) hepatitis C virus (HCV) infection, as well as spontaneous clearance of HCV, was reported. Since the initial publications, over 100 articles have appeared in the peer-reviewed literature, with many more manuscripts in press and abstracts presented at scientific meetings. Despite the proliferation of data concerning the IL28B polymorphism and HCV infection, there remain many critical unanswered questions about clinical implications and the underlying biological mechanisms. In this review, we discuss the basic principles of genome-wide association study methodologies that are important for interpreting the results of genetic association studies. We then review the current literature concerning the association between IL28B variants and interferon (IFN) treatment response in patients with chronic HCV infection, as well as spontaneous HCV clearance. We consider the relevance of the IL28B polymorphism to non-G1 HCV, as well as the special treatment populations of HIV/HCV co-infection and recurrent HCV post-liver transplantation. We review current knowledge of the biological mechanisms underlying this genetic association, including the link to liver IFN-stimulated gene expression, and identify continuing gaps in our knowledge and key research priorities. Finally, pegylated-IFN and ribavirin is no longer the standard of care for the treatment of G1 HCV, and we conclude by considering the relevance of IL28B polymorphisms in the era of direct-acting antivirals.

Predicting response to therapy in chronic hepatitis C: an approach combining interleukin-28B gene polymorphisms and clinical data

BACKGROUND AND AIM

Polymorphisms at the interleukin-28B (IL28B) gene predict therapeutic response in chronic hepatitis C virus genotype 1 (CHC-1) infection. The aim of the present study was to establish whether a unique single-nucleotide polymorphism (SNP) represents the whole predictive value of the IL28B haplotype for sustained viral response (SVR) and primary non-response (PNR).

METHODS

SNP rs12979860 and rs8099917 were determined by TaqMan assays in 110 CHC-1 Caucasian patients treated with pegylated interferon plus ribavirin.

RESULTS

There were 51 SVR, 43 PNR, and 16 relapses. Baseline predictors of SVR were rs12979860CC genotype (P = 0.008), viral load < 400.000 IU/mL (P < 0.010), age (P = 0.013), γ-glutamyl transferase (P = 0.022), alkaline phosphatase (P = 0.008), and cholesterol (P = 0.048). The area under the receiver-operating curve (AUROC) of the model, including these variables, was 0.841 (95% confidence interval [CI] = 0.767-0.916). The same figures for PNR were rs12979860 T-allele carrier state (P = 0.00008), viral load ≥ 400.000 IU/mL (P = 0.007), aspartate aminotransferase/alanine aminotransferase (P = 0.048), and serum cholesterol (P = 0.064), (AUROC = 0.869, 95% CI = 0.792-0.945). After excluding rs12979860CT SNP from multivariate analyses, the rs8099917 genotype alone did not predict SVR (P = 0.185), but strongly predicted PNR (P = 0.003). The significance of haplotypes combining both SNP as predictors of SVR and PNR was higher than those of each separate SNP.

CONCLUSIONS

The rs12979860 SNP strongly predicts therapeutic response in CHC-1 patients, and if associated with easy-to-obtain baseline criteria, provides a useful tool for the selection of candidates for antiviral therapy. IL28B haplotypes might improve the clinical usefulness of individual SNP.

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.

Predictive value of early viral dynamics during peginterferon and ribavirin combination therapy based on genetic polymorphisms near the IL28B gene in patients infected with HCV genotype 1b

A study was carried out to determine whether early viral dynamics retain prediction of the outcome of peginterferon (PEG-IFN) and ribavirin combination therapy based on different genetic polymorphisms near the IL28B gene, the strongest baseline predictor of response to this therapy. A total of 272 patients infected with hepatitis C virus (HCV) genotype 1b were grouped according to genetic polymorphisms near the IL28B gene (rs8099917). The ability of reduced HCV RNA levels at 4 and 12 weeks after starting therapy to predict a sustained virologic response was evaluated based on these genotypes. Among patients with the TT genotype for rs8099917 (associated with a favorable response), the rates of sustained virologic response were higher in patients with a ≥3 log(10) reduction in serum HCV RNA levels at 4 weeks after starting therapy (P < 0.0001). In contrast, among patients with the TG/GG genotype (associated with an unfavorable response), there were no differences in this rate based on the reduction in HCV RNA levels at 4 weeks. Early viral dynamics at 4 weeks after starting therapy retains its predictive value for sustained virologic response in patients with the TT genotype for rs8099917, but not in patients with the TG/GG genotype. Patients who are likely to achieve sustained virologic response despite unfavorable TG/GG genotype cannot be identified based on early viral dynamics during therapy. In contrast, lack of early virologic response at 12 weeks retains a strong predictive value for the failure of sustained virologic response regardless of IL28B polymorphisms, which remains useful as a factor to stop therapy.

Age and total ribavirin dose are independent predictors of relapse after interferon therapy in chronic hepatitis C revealed by data mining analysis

BACKGROUND

This study aimed to define factors associated with relapse among responders to pegylated interferon (PEG-IFN) plus ribavirin (RBV) therapy in chronic hepatitis C.

METHODS

A cohort of genotype 1b chronic hepatitis C patients treated with PEG-IFN plus RBV and who had an undetectable HCV RNA by week 12 (n=951) were randomly assigned to model derivation (n=636) or internal validation (n=315) groups. An independent cohort (n=598) were used for an external validation. A decision tree model for relapse was explored using data mining analysis.

RESULTS

The data mining analysis defined five subgroups of patients with variable rates of relapse ranging from 13% to 52%. The reproducibility of the model was confirmed by internal and external validations (r(2)=0.79 and 0.83, respectively). Patients with undetectable HCV RNA at week 4 had the lowest risk of relapse (13%), followed by patients <60 years with undetectable HCV RNA at week 5-12 who received ≥3.0 g/kg of body weight of RBV (16%). Older patients with a total RBV dose <3.0 g/kg had the highest risk of relapse (52%). Higher RBV dose beyond 3.0 g/kg was associated with further decrease of relapse rate among patients <60 years (up to 11%) but not among older patients whose relapse rate remained stable around 30%.

CONCLUSIONS

Data mining analysis revealed that time to HCV RNA negativity, age and total RBV dose was associated with relapse. To prevent relapse, ≥3.0 g/kg of RBV should be administered. Higher dose of RBV may be beneficial in patients <60 years.

Interleukin 28B genetic polymorphisms and viral factors help identify HCV genotype-1 patients who benefit from 24-week pegylated interferon plus ribavirin therapy

BACKGROUND

Interleukin 28B (IL28B) single nucleotide polymorphism (SNP) genotypes and viral factors can predict sustained virological response (SVR) in HCV genotype-1 (HCV-1) patients receiving 48 weeks of pegylated interferon and ribavirin. Whether these factors would identify those patients who can benefit from a shorter duration of therapy remains unclear.

METHODS

Treatment-naive HCV-1 patients (n=662) receiving 24 or 48 weeks of combination therapy were enrolled. Baseline demographic data, HCV viral load, IL28B SNP genotypes (rs8099917), duration of therapy and rapid virological response (RVR) were evaluated to predict SVR. The SVR rates were further stratified by the independent factors and compared.

RESULTS

The IL28B rs8099917 TT genotype, low baseline viral load (HCV RNA≤600,000 IU/ml), RVR and 48-week therapy independently predicted SVR. In RVR patients with the IL28B rs8099917 TT genotype, the SVR rate of 24-week therapy was comparable to 48-week therapy (95% versus 99%; P=0.21) at low baseline viral load, but was inferior to 48-week therapy (70% versus 97%; P<0.001) at high baseline viral load. In non-RVR patients, the SVR rate of 24-week therapy was inferior to 48-week therapy for those with the IL28B rs8099917 TT genotype but high baseline viral load (23% versus 62%; P<0.001), and those with the IL28B rs8099917 GT/GG genotype but low baseline viral load (0% versus 33%; P=0.02).

CONCLUSIONS

HCV-1 patients simultaneously bearing the IL28B rs8099917 TT genotype, low baseline viral load and RVR can benefit from a shorter duration of combination therapy.

[Current options for predicting therapeutic response in chronically infected patients with hepatitis C virus genotype 1]

Only about 50% of patients chronically infected with hepatitis C virus genotype 1 achieve a successful response to standard treatment with pegylated interferon-alfa and ribavirin. Moreover, the recently approved protease inhibitors will have to be administered together with these drugs. Consequently, predicting response to standard treatment, ideally before starting it, remains an important challenge. Although several baseline predictors of treatment failure have been described, including clinical and virological factors, none of them is able to provide reliable predictions at the individual level. In addition, the development of multivariate models combining several predictive factors has not yet yielded predictions with the requisite reliability for use in clinical practice. Therefore, further research is needed to improve predictive models and to describe new factors that would enable us to predict treatment outcome with greater reliability and reproducibility. The development of candidate selection algorithms that help clinicians to identify which patients could benefit from the new therapies on the basis of their chances of responding to standard therapy is of major interest for both patient well-being and healthcare expense. This review attempts to provide a view of the current options for predicting the response to pegylated interferon-alfa plus ribavirin therapy in patients chronically infected with hepatitis C virus genotype 1.

Hepatic steatosis in chronic hepatitis C patients infected with genotype 2 is associated with insulin resistance, hepatic fibrosis and affects cumulative positivity of serum hepatitis C virus RNA in peginterferon and ribavirin combination therapy

AIM

  Hepatic steatosis is one of the factors limiting the virological response to interferon-based antiviral therapy for chronic hepatitis C (CH-C) patients infected with genotype 1, while contradictory results have been reported for genotype 2. We aimed to clarify the effect of hepatic steatosis on therapeutic outcome and cumulative positivity of serum HCV RNA in CH-C patients infected with genotype 2 treated by peginterferon (PEG-IFN)α2b and ribavirin (RBV) combination therapy.

METHODS

  A total of 74 treatment-naïve non-cirrhotic CH-C patients infected with genotype 2 who received PEG-IFNα2b and RBV according to the standard regimen were divided into hepatic steatosis 0-10% and >10% groups. The clinical backgrounds, sustained virological response (SVR) rates and cumulative positivity of serum HCV RNA were compared between the two groups.

RESULTS

  Among the 74 patients, 61 (82.4%) had hepatic steatosis 0-10% and 13 (17.6%) had hepatic steatosis >10%. Scores of homeostasis model assessment-insulin resistance and hepatic fibrosis were higher in patients with hepatic steatosis >10% than hepatic steatosis 0-10% (P = 0.040 and 0.042, respectively). Non-SVR was more frequent in patients with hepatic steatosis >10% than hepatic steatosis 0-10% (P = 0.003). Cumulative positivity of serum HCV RNA was significantly higher in patients with hepatic steatosis >10% than hepatic steatosis 0-10% (P = 0.004).

CONCLUSIONS

  In CH-C patients infected with genotype 2 treated by PEG-IFNα2b and RBV combination therapy, hepatic steatosis >10% was associated with increased insulin resistance, advanced hepatic fibrosis and higher cumulative positivity of serum HCV RNA, which lead to a higher risk of non-SVR.

Two IL28B polymorphisms are associated with the treatment response of different genotypes of hepatitis C in different racial populations: A meta-analysis

The purpose of this present meta-analysis is to provide an accurate estimation of the association between two IL28B polymorphisms (rs8099917 and rs12979860) and sustained virological response (SVR) to standard treatment of patients of different racial descent infected with different genotypes of hepatitis C virus (HCV), and also to investigate the possible factors in the IL28B gene that contribute to the different SVR rates of patients with different subtypes of HCV infection across different populations. The electronic database PubMed was searched. Asian patients with a common homozygote (TT vs. TG/GG, OR=3.17; CC vs. CT/TT, OR=3.75) attained a higher rate of SVR, and a similar result was observed in European patients (TT vs. TG/GG, OR=1.74; CC vs. CT/TT, OR=2.50). Furthermore, HCV1-infected patients with a common homozygote (TT vs. TG/GG, OR=2.95; CC vs. CT/TT, OR=4.34) appeared to have a higher SVR rate than those with HCV2/3 (TT vs. TG/GG, OR=1.56; CC vs. CT/TT, OR=1.37). The frequency of the common homozygote in Asian patients was high, followed by European patients and African patients. In all, Asian patients attained a higher SVR rate than European patients (P<0.05). Patients with HCV1 infection had a lower SVR rate than those with HCV2/3 infection (P<0.001). Our results suggest that both the common allele frequency and racial descent itself contribute to the difference in SVR rates across different population groups, and the common allele frequency may partly elucidate the different SVR rates in patients with different genotypes of HCV.

Toll like receptor 3 expression as a novel predictor of response to treatment in chronic hepatitis C virus patients

PURPOSE

This work was carried out to study the level of pretreatment hepatic expression of Toll like receptor 3 (TLR3) among chronic HCV patients, aiming to determine if there are consistent differences in gene expression, between those who show complete early virological response (cEVR) at week-12 of Pegylated-Interferon α-2a plus ribavirin treatment and others who are not responding to this combination, also if this could be used to predict treatment outcomes.

METHOD

A total of 61 chronic hepatitis C patients were enrolled in the study. For all of them, baseline hepatitis C virus (HCV) viral load was determined and TLR3 gene expression was examined in their hepatic percutaneous needle biopsy specimens using a real time-polymerase chain reaction technique. Hepatic TLR3 was also traced using immunohistochemistry. All patients followed a 12-week regimen of Pegylated-Interferon α-2a plus ribavirin then post-treatment viral load was assayed.

RESULTS

Hepatic expression of TLR3 was significantly increased in the non-responder group as compared to those who showed complete early virological response to the used treatment regimen. Using receiver operator characteristic (ROC) curve analysis, a cutoff level of 1.5 was set for TLR3 expression to distinguish responders from non-responders to the 12-week treatment regimen used.

CONCLUSION

In conclusion, measuring the hepatic expression of the interferon stimulated gene, TLR3 could provide a new molecular marker for pre-treatment prediction of complete early viral clearance, thus helping in patients' selection and optimizing treatment outcomes.

IL28B alleles exert an additive dose effect when applied to HCV-HIV coinfected persons undergoing peginterferon and ribavirin therapy

BACKGROUND

Genetic studies have demonstrated a strong association between single nucleotide polymorphisms (SNPs) at IL28B and response to treatment with peginterferon (PEG) and ribavirin (RBV) in HCV monoinfected persons. We sought to test these associations in a prospective PEG / weight based ribavirin (WBR) treatment trial (ACTG A5178) (National Institution of Health registration number NCT00078403) in persons with HCV-HIV coinfection, and to develop a prediction score.

METHODS

We selected subjects enrolled in A5178 who completed at least the first 12 weeks of the trial and had DNA available, and genotyped three SNPs at IL28B (rs12979860, rs12980275, rs8099917). We used multivariate logistic regression analysis to evaluate the association between IL28B SNPs and HCV treatment outcomes and to develop the prediction score.

RESULTS

231 HCV/HIV coinfected subjects were included. We observed a strong association between IL28B genotype and response to therapy among those with genotypes 1 or 4 (odds ratio for complete early virologic responses (cEVR) and sustained virologic response (SVR) was 2.98 [1.7-5.3] and 3.4 [1.7-6.9], respectively, for each additional copy of the C allele of rs12979860). Differences in frequency of the responder allele explained some of the discrepancy in HCV treatment outcomes between blacks and whites. A simple pretreatment prediction score that incorporates the IL28B genotype and baseline HCV viral load has a 93% negative predictive value (NPV) for SVR.

CONCLUSIONS

IL28B SNPs have an additive allele dose effect in predicting HCV treatment outcomes in HCV/HIV coinfected persons and can be incorporated into a simple pretreatment prediction score that could minimize the risk of exposure to PEG/RBV therapy for persons with unfavorable scores.

Analysis of the complete open reading frame of genotype 2b hepatitis C virus in association with the response to peginterferon and ribavirin therapy

BACKGROUND AND AIMS

Patients infected with genotype 2b hepatitis C virus (HCV) generally can achieve favorable responses to pegylated-interferon plus ribavirin therapy (PEG-IFN/RBV). However, a proportion of patients show poorer responses and the correlation between viral sequence variation and treatment outcome remains unclear.

METHODS

The pretreatment complete open reading frame (ORF) sequences of genotype 2b HCV determined by direct sequencing were investigated for correlation with the final outcome in a total of 60 patients.

RESULTS

In this study group, 87.5% (14/16) of non-sustained virological response (non-SVR) patients (n = 16) were relapsers. Compared to sustained virological response (SVR) patients (n = 44), non-SVR patients were older and could not achieve prompt viral clearance after the therapy induction. Comparing each viral protein between the two groups, viral sequences were more diverse in SVR patients and that diversity was found primarily in the E1, p7, and NS5A proteins. In searching for specific viral regions associated with the final outcome, several regions in E2, p7, NS2, NS5A, and NS5B were extracted. Among these regions, part of the interferon sensitivity determining region (ISDR) was included. In these regions, amino acid substitutions were associated with the final outcome in an incremental manner, depending upon the number of substitutions.

CONCLUSIONS

Viral sequences are more diverse in SVR patients than non-SVR patients receiving PEG-IFN/RBV therapy for genotype-2b HCV infection. Through systematic comparison of viral sequences, several specific regions, including part of the ISDR, were extracted as having significant correlation with the final outcome.

Pretreatment prediction of anemia progression by pegylated interferon alpha-2b plus ribavirin combination therapy in chronic hepatitis C infection: decision-tree analysis

BACKGROUND

This study aimed to develop a model to predict the development of severe anemia during pegylated interferon alpha-2b plus ribavirin combination therapy.

METHODS

Data were collected from 1081 genotype 1b chronic hepatitis C patients who were treated at 6 hospitals in Japan. These patients were randomly assigned to a model-building group (n = 691) or an internal validation group (n = 390). Factors predictive of severe anemia (hemoglobin, Hb < 8.5 g/dl) were explored using data-mining analysis.

RESULTS

Hb values at baseline, creatinine clearance (Ccr), and an Hb concentration decline by 2 g/dl at week 2 were used to build a decision-tree model, in which the patients were divided into 5 subgroups based on variable rates of severe anemia ranging from 0.4 to 11.8%. The reproducibility of the model was confirmed by the internal validation group (r² = 0.96). The probability of severe anemia was high in patients whose Hb value was <14 g/dl before treatment (6.5%), especially (a) in those whose Ccr was <80 ml/min (11.8%) and (b) those whose Ccr was ≥ 80 ml/min but whose Hb concentration decline at week 2 was ≥ 2 g/dl (11.5%). The probability of severe anemia was low in the other patients (0.4-2.5%).

CONCLUSIONS

The decision-tree model that included Hb values at baseline, Ccr, and an Hb concentration decline by 2 g/dl at week 2 was useful for predicting the probability of severe anemia, and has the potential to support clinical decisions regarding early dose reduction of ribavirin.

Retreatment of patients with chronic hepatitis C relapsers to a previous antiviral treatment

BACKGROUND

The efficacy of retreatment with pegylated interferon (PEG-IFN) plus ribavirin for patients relapsing after a previous treatment remains to be fully elucidated, although extended treatment seems to be the best option in such cases.

AIM

To evaluate the efficacy of two extended protocols in patients with genotypes 1 or 4, or those with genotypes 2 or 3.

METHODS

A total of 181 patients who had relapsed after a previous antiviral treatment with PEG-IFNα2a plus weight-based ribavirin were offered retreatment with the same dose of both PEG-IFN plus ribavirin, to be continued for 48 weeks in those with genotypes 2 or 3 (group 1), and for 72 weeks in those with genotypes 1 or 4 (group 2).

RESULTS

A total of 59 patients (32.5%) refused the retreatment, while 122 (78 men, 44 women) patients were enrolled in the study: 41 were allocated in group 1 and 81 in group 2. Cirrhosis at baseline (staging 5/6 according to Ishak's score was recorded in 11 patients, six in group 1 and five in group 2). Nine patients (7.3%) in group 2 discontinued the treatment (due to lack of response). The remaining patients completed the treatment and were followed-up for at least 12 months after the treatment. Sustained virological response (SVR) rate was 82.9% in group 1 and 50.6% in group 2.

CONCLUSION

Patients with chronic hepatitis C with 'easy genotypes' relapsers to a previous antiviral treatment have more than 80% probability of achieving a SVR with a 48-week retreatment. Patients with 'difficult genotypes' have more than 50% chance of a SVR after a 72-week extended treatment.

Translating pharmacogenetics into clinical practice: interleukin (IL)28B and inosine triphosphatase (ITPA) polymophisms in hepatitis C virus (HCV) infection

Hepatitis C virus (HCV) infection is frequently characterized by evolution to chronicity and by a variable clinical course of the disease. The clinical heterogeneities of HCV infection and the imperfect predictability of the response to interferon (IFN) have suggested the need to search for a genetic basis of clinical features. This led to the discovery of genetic polymorphisms playing a major role in the evolution of infection, as well as on treatment response and adverse effects. This review will cover recent reports on the subject, focusing on the potential use of the new genetic markers in the diagnostic algorithm for the stratification of patients for personalized antiviral regimens.

Cholesterol and chronic hepatitis C virus infection

Cholesterol is an essential molecule for the life cycle of the hepatitis C virus (HCV). This review focuses on the roles of cholesterol in HCV infection and introduces HCV events related to cholesterol metabolism and applications for cholesterol metabolism as a therapeutic target. HCV appears to alter host lipid metabolism into its preferable state, which is clinically recognized as steatosis and hypocholesterolemia. While hepatic fatty acid and triglyceride syntheses are upregulated in chronic hepatitis C patients, no direct evidence of increased hepatic de novo cholesterol biosynthesis has been obtained. Impaired VLDL secretion from hepatocytes is suggested to increase intracellular cholesterol concentrations, which may lead to hypocholesterolemia. Clinically, lower serum cholesterol levels are associated with lower rates of sustained virological responses (SVR) to pegylated-interferon plus ribavirin therapy, but the reason remains unclear. Clinical trials targeting HMG-CoA reductase, the rate-limiting enzyme in the cholesterol biosynthetic pathway, are being conducted using statins. Anti-HCV actions by statins appear to be caused by the inhibition of geranylgeranyl pyrophosphate synthesis rather than their cholesterol lowering effects. Other compounds that block various steps of cholesterol metabolic pathways have also been studied to develop new strategies for the complete eradication of this virus.

Amino acid substitution in HCV core/NS5A region and genetic variation near IL28B gene affect treatment efficacy to interferon plus ribavirin combination therapy

OBJECTIVE

To evaluate predictive factors of treatment efficacy to interferon (IFN)/ribavirin in patients infected with HCV genotype 1b (HCV-1b).

METHODS

This study investigated pretreatment predictors, including viral- (aa substitutions in core aa 70/91 and NS5A-ISDR/IRRDR) and host-related factors (genetic variation near IL28B gene), to 48-week IFN/ribavirin in 490 Japanese adults infected with HCV-1b.

RESULTS

The proportion of patients who showed end-of-treatment response (ETR), sustained virological response (SVR), and SVR after ETR was 76, 54, and 76%, respectively. There was a significant positive correlation between the number of aa substitutions in ISDR and those in IRRDR. Concerning the substitution of core aa 91, the number of aa substitutions in ISDR/IRRDR of patients with Leu91 was significantly higher than that of patients with Met91. Furthermore, levels of viremia were influenced by aa substitutions in core aa 91 and ISDR/IRRDR. By multivariate analysis, rs8099917 genotype was an important predictor of ETR and SVR. With regard to viral factors, core aa 70/91 was an important predictor of ETR, and SVR after ETR. ISDR was an important predictor of SVR, and SVR after ETR.

CONCLUSION

aa substitution in core/NS5A region and genetic variation near IL28B were important predictors of treatment efficacy to IFN/ribavirin.

Sequences in the interferon sensitivity-determining region and core region of hepatitis C virus impact pretreatment prediction of response to PEG-interferon plus ribavirin: data mining analysis

The aim of the present study was to clarify the significance of viral factors for pretreatment prediction of sustained virological response to pegylated-interferon (PEG-IFN) plus ribavirin (RBV) therapy for chronic hepatitis C using data mining analysis. Substitutions in the IFN sensitivity-determining region (ISDR) and at position 70 of the HCV core region (Core70) were determined in 505 patients with genotype 1b chronic hepatitis C treated with PEG-IFN plus RBV. Data mining analysis was used to build a predictive model of sustained virological response in patients selected randomly (n = 304). The reproducibility of the model was validated in the remaining 201 patients. Substitutions in ISDR (odds ratio = 9.92, P < 0.0001) and Core70 (odds ratio = 1.92, P = 0.01) predicted sustained virological response independent of other covariates. The decision-tree model revealed that the rate of sustained virological response was highest (83%) in patients with two or more substitutions in ISDR. The overall rate of sustained virological response was 44% in patients with a low number of substitutions in ISDR (0-1) but was 83% in selected subgroups of younger patients (<60 years), wild-type sequence at Core70, and higher level of low-density lipoprotein cholesterol (LDL-C) (≥ 120 mg/dl). Reproducibility of the model was validated (r(2) = 0.94, P < 0.001). In conclusion, substitutions in ISDR and Core70 of HCV are significant predictors of response to PEG-IFN plus RBV therapy. A decision-tree model that includes these viral factors as predictors could identify patients with a high probability of sustained virological response.