Meta-analysis: IL28B polymorphisms predict sustained viral response in HCV patients treated with pegylated interferon-α and ribavirin

Interferon Upregulation Associates with Insulin Resistance in Humans

In humans, insulin resistance is a physiological response to infections developed to supply sufficient energy to the activated immune system. This metabolic adaptation facilitates the immune response but usually persists after the recovery period of the infection and predisposes the hosts to type 2 diabetes and vascular injury. In patients with diabetes, superimposed insulin resistance worsens metabolic control and promotes diabetic ketoacidosis. Pathogenic mechanisms underlying insulin resistance during microbial invasions remain to be fully defined. However, interferons cause insulin resistance in healthy subjects and other population groups, and their production is increased during infections, suggesting that this group of molecules may contribute to reduced insulin sensitivity. In agreement with this notion, gene expression profiles (transcriptomes) from patients with insulin resistance show a robust overexpression of interferon- stimulated genes (interferon signature). In addition, serum levels of interferon and surrogates for interferon activity are elevated in patients with insulin resistance. Circulating levels of interferon- γ-inducible protein-10, neopterin, and apolipoprotein L1 correlate with insulin resistance manifestations, such as hypertriglyceridemia, reduced HDL-c, visceral fat, and homeostasis model assessment-insulin resistance. Furthermore, interferon downregulation improves insulin resistance. Antimalarials such as hydroxychloroquine reduce interferon production and improve insulin resistance, reducing the risk for type 2 diabetes and cardiovascular disease. In addition, diverse clinical conditions that feature interferon upregulation are associated with insulin resistance, suggesting that interferon may be a common factor promoting this adaptive response. Among these conditions are systemic lupus erythematosus, sarcoidosis, and infections with severe acute respiratory syndrome-coronavirus-2, human immunodeficiency virus, hepatitis C virus, and Mycobacterium tuberculosis.

Association between IL28B Polymorphisms and Outcomes of Hepatitis B Virus Infection: A meta-analysis

BACKGROUND

Interleukin (IL) 28B polymorphisms encoding pro-inflammatory and anti-inflammatory cytokines trigger diverse clinical outcome of hepatitis virus infection. However, there is controversy concerning the association of IL28B polymorphisms with the outcome of hepatitis B virus (HBV) infection, with several studies obtaining inconsistent results. We performed a meta-analysis to evaluate the role of 3 single nucleotide polymorphisms (SNPs) rs12979860, rs12980275 and rs8099917 in the progression of HBV infection, overall and by ethnicity.

METHODS

Searched PubMed, Embase and Wiley Online Library electronic databases using 'interleukin 28B', 'IL 28B', 'IL 28B polymorphism', 'hepatitis B virus', 'HBV', and performed meta- analysis for rs12979860, rs12980275 and rs8099917 in Asian and Caucasian populations under the dominant recessive and allele model.

RESULTS

Eighteen studies were found in total and used for this meta-analysis, including 5587 cases and 4295 controls. The IL28B polymorphism rs12979860 had no association with HBV persistence (CC vs CT + TT: OR = 0.86, 95% CI = 0.76-1.00; TT vs CT + CC: OR = 1.14, 95% CI = 0.76-1.70; T vs C: OR = 1.03, 95% CI = 0.94-1.13). Similarly, neither rs12980275 nor rs8099917 had associations with HBV persistence (rs12980275 in AA vs AG + AA: OR = 1.15, 95% CI = 0.96-1.38; rs8099917 in TT vs GT + GG: OR = 1.15, 95% CI = 0.96-1.39). There was also no significant association of IL28B polymorphisms with persistent HBV infection in Asians or Chinese. There was no evidence of an association of rs12979860 with the HBV-related hepatocellular carcinoma susceptibility (T vs C: OR = 1.53, 95% CI = 0.96-2.43).

CONCLUSION

IL28B polymorphisms had no association with the outcome of HBV infection overall, nor in the Asians and the Chinese. These 3 SNPs might not be relevant to the development of HBV infection.

Hepatitis C virus protein interaction network for HCV clearance and association of DAA to HCC occurrence via data mining approach: A systematic review and critical analysis

HCV has been associated with a pro-inflammatory state, which predisposes to hepatocellular carcinoma (HCC). However, the different molecular mechanisms underlying the effect of HCV infection on HCC progression remain unclear. Although HCV infection illustrates the potential role of host genetics in the outcome of infectious diseases, there is no clear overview of some single nucleotide polymorphisms (SNPs) influencing spontaneous or treatment-induced HCV eradication. We studied the possible role of HCV infection in the processes of HCC initiation and performed a systematic analysis using data mining approaches to identify host polymorphisms associated with treatment response and HCC development using topological analysis of protein-proteins interactions (PPI) networks. On the basis of our analysis performed, we identified key hub proteins related to HCV-treatment response infection and to HCC development. Host genetic polymorphisms, such as inosine triphosphatase (ITPA), interferon, lambda 3 (IFNL3), Q5 interferon, lambda 4 (IFNL4), toll-like receptors (TLRs) and interferon-stimulated gene 15 (ISG-15), were identified as key genes for treatment prediction and HCC evolution. By comparing unique genes for HCV-treatment response and genes particular to HCV-HCC development, we found a common PPI network that may participate in more extensive signalling processes during anti-HCV treatment, which can play important roles in modulating the immune response to the occurrence of HCC. Data mining is an effective tool for identifying potential regulatory pathways involved in treatment response and HCC development. Our study may contribute to a better understanding of HCV immunopathogenesis and highlights the complex role of host genetics in HCV clearance.

Relationship between antibodies to hepatitis C virus core+1 protein and treatment outcome

Background

It has been suggested that hepatitis C virus (HCV) core+1 protein plays a crucial role in the viral life cycle, potentially affecting liver cirrhosis and the development of hepatocellular carcinoma.

Methods

To investigate its relationship with the outcome of HCV standard combination therapy with peginterferon-α plus ribavirin, we screened 139 consecutive HCV patients (119 with chronic HCV infection and 20 who spontaneously cleared HCV) for the presence of anti-core+1 antibodies (Abs). In addition, liver fibrosis was determined by FibroScan in all but one patients.

Results

Twenty-nine patients were cirrhotic (stiffness >12.5 kPa, F4 METAVIR), all of them with mild liver cirrhosis (Child-Pugh score A). Eighty-six of 139 patients were treatment-experienced with standard combination therapy. Fifty of them had achieved a sustained virological response, while 36 were non-responders. The prevalence of anti-core+1 Abs in patients with chronic HCV infection was 22.69% (27/119 patients): 18% (9/50 patients) in responders and 36.11% (13/36 patients) in non-responders (P=0.050). Five (17.24%) of the 29 cirrhotic patients and 22 (24.72%) of the 89 non-cirrhotic patients were positive for anti-core+1 Abs (P=0.405). Furthermore, the presence of anti-core+1 Abs correlated with the poor response interleukin (IL) 28B genotype TT (P=0.040). No correlation between spontaneous clearance and anti-core+1 Abs was observed (P=0.088).

Conclusion

The presence of anti-core+1 Abs might be correlated with the poor response IL28B TT genotype and may negatively affect the outcome of standard combination treatments in HCV patients, suggesting that core+1 may play a biological role in the course of HCV infection.

No association between IFNL3 (IL28B) genotype and response to peginterferon alfa-2a in HBeAg-positive or -negative chronic hepatitis B

BACKGROUND & AIMS

It has yet to be firmly established whether host IFNL3 (IL28B) genotype influences interferon responsiveness in patients with chronic hepatitis B. We investigated associations between single-nucleotide polymorphisms (SNPs) in the IFNL3 region and response to peginterferon alfa-2a in 701 patients enrolled in three large, randomized, international studies.

METHODS

Responses were defined as hepatitis B surface antigen (HBsAg) loss and/or hepatitis B e antigen (HBeAg) seroconversion plus hepatitis B virus (HBV) DNA <2000 IU/ml in HBeAg-positive patients, and HBsAg loss and/or HBV DNA <2000 IU/ml in HBeAg-negative patients (24 weeks after end of treatment). Associations between treatment response and the number of copies of the poor-response allele at three SNPs (rs8099917, rs12980275, rs12979860) were explored with logistic regression models in Asian and white patients.

RESULTS

The HBeAg-positive and -negative populations comprised 465 (92% Asian, 50% HBV genotype C) and 236 (79% Asian, 41% HBV genotype C) patients, respectively, and had respective response rates of 26% and 47%. The IFNL3 genotype was strongly associated with ethnicity. There was no association between IFNL3 genotype and treatment response in HBeAg-positive or -negative patients. Independent predictors of treatment response were: sex, HBV DNA level and alanine aminotransferase level in HBeAg-positive Asian patients; age in HBeAg-negative Asian patients; and HBV DNA in HBeAg-negative white patients.

CONCLUSIONS

This is the largest analysis to date of associations between IFNL3 genotype and peginterferon response in patients with chronic hepatitis B. The data suggest that IFNL3 polymorphism is not a major determinant of the response to peginterferon alfa-2a in either HBeAg-positive or HBeAg-negative patients.

Pegylated interferon alpha 2a for the treatment of hepatitis C virus infection

INTRODUCTION

Treatments for hepatitis C virus (HCV) infection have advanced rapidly in the last decade. Pegylated interferon alpha 2a (PEG-IFN alpha 2a) alone, in combination with ribavirin and with or without direct acting antivirals (DAAs) is modestly effective in the treatment of chronic HCV infection. Areas covered: The review describes the chemistry, pharmacokinetic and pharmacodynamic properties, clinical efficacy, safety and drug-drug interaction profiles of PEG-IFN alpha 2a. Expert opinion: Despite the availability of DAAs and its formidable toxicity profile, PEG-IFN alpha 2a retains a role for the treatment of acute HCV and chronic HCV infection in resource limited settings and for end-stage renal disease patients and others who cannot access DAAs or are DAA-ineligible. Knowledge of pharmacogenetic profiles which favor successful treatment outcomes with IFN-based therapies may allow for selection of best candidates for the regimen.

Safety and efficacy of sofosbuvir-based direct-acting antiviral regimens for hepatitis C virus genotypes 1-4 and 6 in Myanmar: Real-world experience

This open-label, clinical experience investigated the safety and efficacy of direct-acting antiviral (DAA) hepatitis C virus (HCV) therapy in Myanmar; 344 patients completed treatment between June 2015 and May 2016. Patients with HCV genotypes 1-4 and 6 received one of four treatments: (i) Peg-interferon (PEG-IFN)+sofosbuvir (SOF)+ribavirin (RBV) for 12 weeks, (ii) SOF+RBV for 24 weeks, (iii) ledipasvir (LDV)+SOF for 12 weeks or (iv) daclatasvir (DCV)+SOF+RBV for 12 or 24 weeks. Genotype 3 was most common (n=133, 38.7%), followed by genotype 6 (n=122, 35.5%) and genotype 1 (n=86, 25%). Overall, 91% of patients achieved sustained virologic response (SVR); 99% in group 1, (n=148/149), 90% in group 2 (n=95/106), 78% in group 3 (n=65/83) and 100% in group 4 (n=6/6). In group 3, SVR rates were 96.8% in genotype 1 (n=30/31) and 64.1% in genotype 6 (n=25/39). Multivariable regression analysis identified advanced fibrosis (F3-4) (OR=.16 CI: 0.05-0.57, P=.005), genotype 6 (OR=.35, CI: 0.16-0.79, P=.012) and diabetes (OR=.29, CI: 0.12-0.71, P=.007) as negative independent predictors of response. Adverse events were mild with all-oral therapy.

CONCLUSION

DAA therapy ±PEG-IFN achieved high SVR rates. Genotype 6 patients had a low SVR to 12 weeks of LDV and SOF raising the need for other regimens, RBV or longer treatment duration in this population.

Peginterferon alfa-2a for the treatment of chronic hepatitis C in the era of direct-acting antivirals

BACKGROUND

The availability of novel direct-acting antivirals (DAAs) represents a new era of curative hepatitis C virus (HCV) treatment, with over 95% of patients infected with HCV genotype 1 achieving sustained virological response (SVR). Nevertheless, the majority of patients globally are unable to access these treatments because of cost and infrastructure constraints and, thus, remain untreated and uncured.

DATA SOURCE

Relevant articles of peginterferon (PegIFN)-based treatments in HCV and sofosbuvir-based treatments, simeprevir, daclatasvir/asunaprevir, ritonavir-boosted paritaprevir/ombitasvir/dasabuvir, and grazoprevir/elbasvir, were searched in PubMed database, including general population and special population.

RESULTS

PegIFN in combination with ribavirin remains an important and relevant option for some patients, achieving SVR rates of up to 79% in genotype 1 and 89% in genotype 2 or 3 infections, which increases for patients with favorable IL28B genotypes. Triple therapy of DAA plus PegIFN/ribavirin is effective in treating difficult-to-cure patients infected with HCV genotype 3 or with resistance-associated variants. Owing to its long history in HCV management, the efficacy, tolerability and long-term outcomes associated with PegIFN alfa-2a are well established and have been validated in large-scale studies and in clinical practice for many populations. Furthermore, emerging data show that IFN-induced SVR is associated with lower incidences of hepatocellular carcinoma compared with DAAs. On the contrary, novel DAAs have yet to be studied in special populations, and long-term outcomes, particularly tumor development and recurrence in patients with cirrhosis and/or hepatocellular carcinoma, and reactivation of HBV in dually infected patients, are still unclear.

CONCLUSION

In this interferon-free era, PegIFN-based regimens remain a safe and effective option for selected HCV patients.

High frequencies of a favorable IL-28B rs8099917 polymorphism and the clinical implications in patients with HCV in one multiracial area of Taiwan

There is a strong association between hepatitis C virus (HCV) treatment efficacy and the interleukin (IL)-28B gene. However, the IL-28B variant's distribution and potential role in the therapeutic response are not well established in Taitung, a racially diverse county in Taiwan. Here, we investigated the distribution pattern of IL-28B rs8099917 and its influence on treatment efficacy. In this retrospective study, we enrolled 180 patients who had been treated with pegylated-interferon plus ribavirin. Patients' general information, virological characteristics, IL-28B status, laboratory results, treatment course, and outcome were analyzed. Of the patients enrolled, 56.7% were male, with a mean age of 54.11 years. A total of 24.4% of the population were indigenous people. The majority of patients had the favorable IL-28B polymorphism (rs8099917 TT/TG/GG: 94.4%/5.6%/0%). The proportion of patients with the TT genotype seemed to be higher in indigenous patients. The rate of sustained virological response (SVR) among included patients was 73.0%. Univariate analysis showed that genotype non-1, patients achieved rapid virological response (RVR), lower body mass index (BMI), and lower baseline HCV viral load were significantly associated with SVR. Multivariate analysis revealed that BMI <25 and RVR are the independent predictor of success treatment. In conclusion, the favorable IL-28B rs8099917 polymorphism occurs in high frequency in this multiracial area, which might be important to help guide physicians and patients in their future clinical decisions.

Molecular characterization and epidemic history of hepatitis C virus using core sequences of isolates from Central Province, Saudi Arabia

The source of HCV transmission in Saudi Arabia is unknown. This study aimed to determine HCV genotypes in a representative sample of chronically infected patients in Saudi Arabia. All HCV isolates were genotyped and subtyped by sequencing of the HCV core region and 54 new HCV isolates were identified. Three sets of primers targeting the core region were used for both amplification and sequencing of all isolates resulting in a 326 bp fragment. Most HCV isolates were genotype 4 (85%), whereas only a few isolates were recognized as genotype 1 (15%). With the assistance of Genbank database and BLAST, subtyping results showed that most of genotype 4 isolates were 4d whereas most of genotype 1 isolates were 1b. Nucleotide conservation and variation rates of HCV core sequences showed that 4a and 1b have the highest levels of variation. Phylogenetic analysis of sequences by Maximum Likelihood and Bayesian Coalescent methods was used to explore the source of HCV transmission by investigating the relationship between Saudi Arabia and other countries in the Middle East and Africa. Coalescent analysis showed that transmissions of HCV from Egypt to Saudi Arabia are estimated to have occurred in three major clusters: 4d was introduced into the country before 1900, the major 4a clade’s MRCA was introduced between 1900 and 1920, and the remaining lineages were introduced between 1940 and 1960 from Egypt and Middle Africa. Results showed that no lineages seem to have crossed from Egypt to Saudi Arabia in the last 15 years. Finally, sequencing and characterization of new HCV isolates from Saudi Arabia will enrich the HCV database and help further studies related to treatment and management of the virus.

Demographic profile, host, disease & viral predictive factors of response in patients with chronic hepatitis C virus infection at a tertiary care hospital in north India

Background & objectives:

Standard of care for chronic hepatitis C (CHC) in India is peginterferon and ribavirin (RBV). The response to treatment in real life stetting is unclear. The objectives of this study were to evaluate the demographic profile and assess the virological response and predictors of response in CHC patients.

Methods:

Consecutive patients with CHC were included in this study. Detailed clinical history, risk factors, and predictive factors of response were noted. Patients were treated with peginterferon α2b (1.5 µg/kg/wk) and RBV (12 mg/kg/day) for 6 to 18 months based on response.

Results:

A total of 211 patients were included in the analysis, mean age 40.6±12.3 yr, 144 (68%) were males and 71 (34%) had compensated cirrhosis. Commonest risk factor for acquiring CHC was previous transfusion and surgery (51%). Genotype 3 (72%) was most common followed by genotype 1 (23%). Overall sustained virologic response (SVR) was 64 per cent [95% CI 57.1%-70.4%]. The SVR was 66.5 per cent [95% CI 58.34-73.89%] for genotype 3 and 61.2 per cent [95% CI 46.23 to 74.80%] for genotype 1. Non-cirrhotics had better SVR rates compared to cirrhotics (76 vs 41%, P<0.001). On multivariate analysis, BMI ≥23 kg/m², HOMA-IR ≥2, compliance (≤80%), and fibrosis >2 were predictors of low SVR.

Interpretation & conclusions:

Genotype 3 was the commonest HCV genotype. The commonest source of infection was previous transfusion and surgery. SVR rates for genotypes 3 were better than genotype 1 patients. Predictors of non-response were high BMI, insulin resistance, significant fibrosis and inadequate compliance.

Urgency to treat patients with chronic hepatitis C in Asia

Chronic hepatitis C (CHC) infection poses a global healthcare burden, being associated with serious complications if untreated. The prevalence of hepatitis C virus (HCV) infection is highest in areas of Central, South, and East Asia; over 50% of HCV patients worldwide live in the region, where HCV genotypes 1b, 2, 3, and 6 are the most prevalent. Treatment outcomes for chronic hepatitis C vary by ethnicity, and Asian patients achieve higher sustained virologic response rates following interferon (IFN)-based therapy than non-Asians. However, low efficacy, poor safety profile, and subcutaneous administration limit the use of IFN-based therapies. Superior virologic outcomes have been observed with different classes of direct-acting antivirals (DAAs) alone or in combination, and several all-oral DAA regimens are available in Asia. These regimens have shown excellent efficacy and favorable tolerability in clinical trials, yet there is a need for further studies of DAAs in a real world context, particularly in Asia. Furthermore, IFN-free treatment may not be accessible for many patients in the region, and IFN-based regimens remain an option in some countries. There is a need to improve current clinical practices for HCV management in Asia, including effective screening, disease awareness, and prevention programs, and to further understand the cost-effectiveness of IFN-free regimens. The evolution of potent treatments makes HCV eradication a possibility that should be available to all patients. However, access to these therapies in Asian countries has been slow, primarily because of economic barriers that continue to present a hurdle to optimal treatment.

Genotype 3 Infection: The Last Stand of Hepatitis C Virus

Hepatitis C virus (HCV) represents a significant global disease burden, with an estimated 130-150 million people worldwide living with chronic HCV infection. Within the six major clinical HCV genotypes, genotype 3 represents 22-30% of all infection and is described as a unique entity with higher rates of steatosis, faster progression to cirrhosis, and higher rates of hepatocellular carcinoma. Hepatic steatosis in the setting of hepatitis C genotype 3 (HCV-3) is driven by viral influence on three major pathways: microsomal triglyceride transfer protein, sterol regulatory element-binding protein-1c, and peroxisome proliferator-associated receptor-α. Historically with direct-acting antivirals, the rates of cure for HCV-3 therapies lagged behind the other genotypes. As current therapies for HCV-3 continue to close this gap, it is important to be cognizant of common drug interactions such as acid-suppressing medication and amiodarone. In this review, we discuss the rates of steatosis in HCV-3, the mechanisms behind HCV-3-specific steatosis, and current and future therapies.

Hepatitis C virus therapy with peg-interferon and ribavirin in Myanmar: A resource-constrained country

AIM

To investigate peg-interferon (peg-IFN) and ribavirin (RBV) therapy in Myanmar and to predict sustained virologic response (SVR).

METHODS

This single-center, open-label, study was conducted in Myanmar between 2009 and 2014. A total of 288 patients infected with HCV genotypes 1, 2, 3 and 6 were treated with peg-IFN alpha-2a (180 μg/wk) or alpha-2b (50 to 100 μg as a weight-based dose) and RBV as a weight-based dose (15 mg/kg/d). Treatment duration was 48 wk for genotypes 1 and 6, 24 wk for genotype 2, and 24 or 48 wk for genotype 3 based on rapid virologic response (RVR). Those co-infected with hepatitis B received 48 wk of therapy.

RESULTS

Overall, SVR was achieved for 82% of patients and the therapy was well tolerated. All patients achieved SVR at equivalent rates regardless of HCV genotype (P = 0.314). Low fibrosis scores (P < 0.001), high baseline albumin levels (P = 0.028) and low baseline viral loads (P = 0.029) all independently predicted SVR. On the other hand, IL-28B TT and CC genotypes were not found to significantly predict SVR (P = 0.634; P = 0.618). Among those who completed treatment, the occurrence of RVR showed a > 96% positive predictive value for achieving SVR. Treatment duration did not significantly impact the likelihood of achieving SVR for patients infected with genotype 3 HCV (P = 0.371). The most common adverse events were fatigue (71%) and poor appetite (60%). Among patients with genotype 3 HCV, more patients in the 48-wk treatment group required erythropoietin than in the 24-wk treatment group (61.1% vs 49.2%).

CONCLUSION

SVR rates were high with peg-IFN and RBV therapy in Myanmar. Fibrosis scores, baseline albumin, HCV RNA levels and RVR independently predicted SVR.

Impact of IFNL4 rs12979860 and rs8099917 polymorphisms on response to Peg-Interferon-α and Ribavirin in patients with congenital bleeding disorder and chronic hepatitis C

BACKGROUND

The aim of this study was to determine whether two polymorphisms of the human interferon lambda 4 (IFNL4) gene (rs12979860 and rs8099917) can predict sustained virologic response (SVR) following antiviral therapy in patients with inherited bleeding disorder and chronic hepatitis C (CHC).

METHODS

This retrospective study was conducted on 294 patients with congenital bleeding disorder and CHC who were treated with Peg-Interferon-α (PegIFN) and Ribavirin (RBV). Baseline patient and viral parameters were measured and analyzed statistically to assess their combined and individual contributions to SVR prediction.

RESULTS

The most prevalent variants of rs12979860 and rs8099917 identified among the study patients were CT (45.9%) and TT (57.6%), respectively. Overall, SVR was achieved in 69% of the study patients. The rate of SVR was lower in patients with HCV genotype-1 than in those with HCV genotype-3 (62% vs 88%; P<.001; OR=0.23). Multivariate analysis of SVR predictors in patients with HCV genotype-1 infection included age (<24 years), BMI (<25), absence of cirrhosis, HCV RNA level (<400 000 IU/mL), rs8099917 TT and rs12979860 CC, all of which were associated with a higher SVR rate. In HCV genotype-3 infection, only rs12979860 CC was significantly associated with SVR.

CONCLUSION

These results demonstrate that polymorphisms of the IFNL4 gene are highly associated with SVR to PegIFN and RBV combination therapy in patients with a congenital bleeding disorder and CHC. Assessment of rs12979860 and rs8099917 genotypes can guide physicians in choosing an optimal treatment regimen, including less expensive therapies that may only be available in many geographic locales.

[Analysis of ineffective antiviral therapy with pegylated interferon and ribavirin in a patient with chronic hepatitis C infected with HCV genotype 2]

The paper describes a case of ineffective dual antiviral therapy (pegylated interferon and ribavirin) in a patient with chronic hepatitis C infected with hepatitis C virus (HCV) genotype 2 according to the data from the use of a commercial test system. Analysis of the predictors of failure of antiviral therapy (AVT) (the HCV recombinant variant RF2k/1b, a high viral load before the start of therapy, an unfavorable IL-28B genotype, a high body mass index, and a need for a lower ribavirin dose after 12 weeks of AVT because of adverse reactions for less than 4 weeks) in this patient has shown that no virological response is mainly associated with the presence of the HCV recombinant variant, the treatment effectiveness of which is comparable with that in HCV genotype 1 and obesity. In this connection, when HCV genotype 2 is identified, sequencing the NS5B region of the HCV genome is additionally recommended to rule out the virus recombinant strain and, if it is detected, highly effective interferon-free therapy with direct-acting antivirals is indicated.

The Prevalence of Hepatitis C Virus Core Amino Acid 70 Substitution and Genotypes of Polymorphisms Near the IFNL3 Gene in Iranian Patients With Chronic Hepatitis C

BACKGROUND

Molecular studies have demonstrated that the hepatitis C virus (HCV) genotype and host genetics play predictive roles in the management of patients infected with HCV.

OBJECTIVES

This study aimed to investigate the HCV genotype, core amino acid (aa) 70 substitution, and polymorphisms near the IFNL3 gene (including rs12979860 and rs8099917) among Iranian patients with chronic hepatitis C (CHC).

PATIENTS AND METHODS

In this cross-sectional study, the molecular profiles of the HCV genotype, core aa 70 substitution, and rs12979860 and rs8099917 polymorphisms and plasma HCV RNA levels were determined in 429 CHC patients including 141 hemophilic, 84 thalassemic, and 204 non-hemophilic, non-thalassemic patients.

RESULTS

The hepatitis C virus subtype 1a was the most common subtype in the study population. Core aa substitution Arg70Gln was strongly associated with cirrhosis (OR = 2.49; 95% CI = 1.13 - 5.50; P = 0.020). Core aa 70 substitutions were more frequently observed in patients with the HCV subtype 1b than in patients with any other HCV subtypes (P < 0.001). Core aa 70 substitutions were also more common in patients with the rs12979860 TT genotype than in patients with non-TT genotypes (17.3% vs. 8.5%, P = 0.022) and also in rs8099917 non-TT genotypes than in the TT genotype (14.0% vs. 7.0%, P = 0.026). The HCV genotypes and rs8099917 polymorphisms were correlated in which HCV subtype 1b was in favor of rs8099917 GG and HCV subtype 3a favored rs8099917 TT (P = 0.021). Furthermore, the rs12979860 TT and rs8099917 GG genotypes showed significantly lower HCV RNA levels than the other genotypes (P < 0.001).

CONCLUSIONS

There is an as yet unexplained association between HCV and host parameters with unknown mechanisms in patients with chronic HCV infection. The assessments of core aa 70 substitution and polymorphisms near the IFNL3 gene could offer promising steps to improve the management of patients with HCV.

GAMMA GLUTAMYLTRANSFERASE IMPACT IN THERAPEUTIC RESPONSE OF CHRONIC HEPATITIS C: a systematic review of the literature

BACKGROUND

The standard treatment of chronic hepatitis C is the administration of pegylated interferon α2a or α2b in combination with ribavirin, but adverse effects can be observed, as well as the high cost of this therapy. Therefore, there is interest in understanding the predictors of sustained virologic response, as the gamma glutamyltransferase.

OBJECTIVE

To evaluate the serum levels of gamma glutamyltransferase as a predictor of response to treatment with pegylated interferon α and ribavirin in chronic hepatitis C.

METHODS

This is a systematic review of literature, conducted by consulting PUBMED, LILACS, MEDLINE, SCOPUS, Cochrane electronic databases, and active search of articles selected between January 2000 and April 2013.

RESULTS

A total of 4,785 titles were identified. Out of those material, following inclusion and exclusion criteria, 273 abstracts were selected, by two independent researchers. After reading those texts, the reviewers consensually included ten studies for systematization and classification, according to the criteria of the Oxford Scale. 1B studies are predominant (prospective cohort study - six studies). Rapid virologic response and early virological response were considered as estimates for the sustained virological response. The frequency of virologic response was identified in three studies and early virological response in two, with a total of 392 and 413 patients, respectively; sustained virologic response was reported in nine articles corresponding to 3,787 patients (76.5 %).

CONCLUSION

Gamma glutamyltransferase is a predictor of sustained virologic response in the treatment of chronic hepatitis C with pegylated interferon α2a or α2b associated with ribavirin.

Interleukin 28B polymorphisms as predictors of sustained virological response in chronic hepatitis C: systematic review and meta-analysis

Polymorphism of interleukin 28B gene represents a powerful outcome predictor for interferon-based regimens in hepatitis C virus infection. However, some studies report conflicting results. The predictive value of interleukin 28B genotype over the outcome interferon-α/ribavirin treatment was thoroughly evaluated and compared with virological predictors of response. Literature revision was performed on PubMed. Pooled odds ratios (ORs) were calculated by fixed- or random-effects models. Heterogeneity and publication bias were also assessed. Sixty-two eligible papers including 20 290 patients were retrieved. Both polymorphisms (rs12979860 and rs8099917) were strongly associated with response (OR=4.09 and 4.00, respectively), however, the association was weaker for subjects infected with viral genotypes 2 and 3 (OR=1.52 and 1.49, respectively). Compared with interleukin 28B genotype, the association with response was lower for baseline viremia (OR=2.15) and higher for rapid virological response (OR=13.86). These results provide a critical evaluation of interleukin 28B genotype as a pharmacogenetic predictor in hepatitis C patients.

Interferon Lambda 4 Polymorphism Predicts Sustained Viral Response in Hepatitis C Virus Patients Irrespective of Hepatitis C Virus Genotypes, Ethnicity or Treatment Regimen: Results From a Meta-Analysis

CONTEXT

There is growing evidence that interferon lambda 4 (IFNL4) polymorphism is related to sustained virological response (SVR) in hepatitis C virus (HCV) infection. We analyzed the relationship between IFNL4 (rs368234815) polymorphism and SVR in dual- and triple- therapy in HCV genotype 1, 2, 3 and 4 infected Asian, Caucasian and African patients.

EVIDENCE ACQUISITION

We performed a systematic search of PubMed, Medline, Embase, EBSCO and Web of Science databases up to July 2015. Data of qualified studies were analyzed using the meta-analysis method in Stata 12.0 software.

RESULTS

Ten studies involving 4765 patients were included in the analysis. Of overall studies, SVR was more frequent in TT/TT genotype compared to TT /ΔG+ΔG /ΔG (OR = 4.439, 95% CI: 3.410 - 5.778). Genotype stratification analyses revealed rs368234815 TT/ TT was associated with higher SVR in G1, G2/3 and G4 HCV patients (ORG1 = 4.661, 95% CI: 3.937 - 5.518; ORG2/3 = 1.896, 95% CI: 1.265 - 2.841; ORG4 = 6.074; 95% CI: 3.129 - 11.788). Ethnicity stratification analyses of G1 patients showed that SVR was more frequent with TT/ TT genotype in Asians (OR= 8.245, 95% CI: 5.475 - 12.416), Caucasians (OR = 4.166, 95% CI: 3.441 - 5.042) and Africans (SVR: 37.5% vs 17.0%, P = 0.017). Moreover, similar results presented in therapy stratification analyses both in patients with dual-therapy (OR = 3.857; 95% CI: 3.288 - 4.524) or triple-therapy (OR = 8.119; 95% CI: 4.942 - 13.340).

CONCLUSIONS

Favorable IFNL4 rs368234815 genotype is a strong predictor of SVR in HCV patients, irrespective of HCV genotypes, ethnicity or treatment regimen. Thus, detection for IFNL4 rs368234815 polymorphism may be beneficial to guide the clinician in the individualization of therapy and design.

Genetic, metabolic and environmental factors involved in the development of liver cirrhosis in Mexico

Liver cirrhosis (LC) is a chronic illness caused by inflammatory responses and progressive fibrosis. Globally, the most common causes of chronic liver disease include persistent alcohol abuse, followed by viral hepatitis infections and nonalcoholic fatty liver disease. However, regardless of the etiological factors, the susceptibility and degree of liver damage may be influenced by genetic polymorphisms that are associated with distinct ethnic and cultural backgrounds. Consequently, metabolic genes are influenced by variable environmental lifestyle factors, such as diet, physical inactivity, and emotional stress, which are associated with regional differences among populations. This Topic Highlight will focus on the genetic and environmental factors that may influence the metabolism of alcohol and nutrients in the setting of distinct etiologies of liver disease. The interaction between genes and environment in the current-day admixed population, Mestizo and Native Mexican, will be described. Additionally, genes involved in immune regulation, insulin sensitivity, oxidative stress and extracellular matrix deposition may modulate the degree of severity. In conclusion, LC is a complex disease. The onset, progression, and clinical outcome of LC among the Mexican population are influenced by specific genetic and environmental factors. Among these are an admixed genome with a heterogenic distribution of European, Amerindian and African ancestry; a high score of alcohol consumption; viral infections; a hepatopathogenic diet; and a high prevalence of obesity. The variance in risk factors among populations suggests that intervention strategies directed towards the prevention and management of LC should be tailored according to such population-based features.

IFN-λ gene polymorphisms as predictive factors in chronic hepatitis C treatment-naive patients without access to protease inhibitors

The single nucleotides polymorphisms analyses in the regions near the IL28B gene in patients chronically infected with genotype 1 hepatitis C virus (HCV) are an important predictive factor for sustained virological response (SVR). The aim was to assess the predictive value of the polymorphisms of the IL28B/IFNL3 gene in patients chronically infected with genotype 1 for the viral clearance obtained after initial treatment including admixed populations. A systematic review was conducted, using a meta-analysis in the PubMed, Embase, LILACS, and SCIELO using MesH and DECS in 42 studies. The parameters were IL28B polymorphisms, rs12979860, rs8099917, and rs12980275, SVR ratio, and OR (odds ratio). OR and confidence Interval of 95% (95%CI), were calculated by fixed or random effects models. Heterogeneity, sensitivity analysis, and publication bias were also performed. Significant differences were noted between carriers groups with the major versus minor allele at rs12979860 CC versus CT/TT-genotype (OR = 4.18; 95%CI = 3.37-5.17), rs8099917 TT versus TG/GG-genotype (OR = 4.07; 95%CI = 2.94-5.63), and rs12980275 AA versus AA/AG-genotype (OR = 5.34; 95%CI = 1.60-17.82). There was selection bias in the rs8099917 analysis (Egger's regression P = 0.049), which reversed after performing a sensitivity analysis (P = 0.510). The incorporation of SNP analyses in IL28B/IFNL3 gene during the diagnosis process in Brazil should be used as a complementary tool to determine the appropriate treatment for HCV genotype 1. Here, we confirm that the rs12979860 CC, rs8099917 TT, and rs12980275 AA genotype-carriers have favorable responses to standard therapy, including two studies with Brazilian population, and this information should be considered.

Role of genetic polymorphisms in hepatitis C virus chronic infection

AIM: To analyze the host genetics factors influencing the clinical course and the response to antiviral treatment in patients with chronic hepatitis C (CHC).

METHODS: We conducted an electronic search on the PubMed and MEDLINE (2000-2014) databases and Cochrane library (2000-2014). A total of 73 articles were retrieved and their data were extensively evaluated and discussed by the authors and then analyzed in this review article.

RESULTS: Several studies associated polymorphisms in the interleukin 28B gene on chromosome 19 (19q13.13) with a spontaneous viral clearance in acute hepatitis C and with the response to pegylated interferon (Peg-IFN)-based treatment in chronic hepatitis C patients. Other investigations demonstrated that inosine triphosphate pyrophosphatase genetic variants protect hepatitis C virus-genotype-1 CHC patients from ribavirin-induced anemia, and other studies that a polymorphism in the patatin-like phospholipase domain-containing protein 3 was associated with hepatic steatosis in CHC patients. Although not conclusive, some investigations suggested that the vitamin D-associated polymorphisms play an important role in the achievement of sustained virologic response in CHC patients treated with Peg-IFN-based antiviral therapy. Several other polymorphisms have been investigated to ascertain their possible impact on the natural history and on the response to treatment in patients with CHC, but the data are preliminary and warrant confirmation.

CONCLUSION: Several genetic polymorphisms seem to influence the clinical course and the response to antiviral treatment in patients with CHC, suggesting individualized follow up and treatment strategies.

Hepatitis C in human immunodeficiency virus co-infected individuals: Is this still a "special population"?

A substantial proportion of individuals with chronic hepatitis C virus (HCV) are co-infected with human immunodeficiency virus (HIV). Co-infected individuals are traditionally considered as one of the "special populations" amongst those with chronic HCV, mainly because of faster progression to end-stage liver disease and suboptimal responses to treatment with pegylated interferon alpha and ribavirin, the benefits of which are often outweighed by toxicity. The advent of the newer direct acting antivirals (DAAs) has given hope that the majority of co-infected individuals can clear HCV. However the "special population" designation may prove an obstacle for those with co-infection to gain access to the new agents, in terms of requirement for separate pre-licensing clinical trials and extensive drug-drug interaction studies. We review the global epidemiology, natural history and pathogenesis of chronic hepatitis C in HIV co-infection. The accelerated course of chronic hepatitis C in HIV co-infection is not adequately offset by successful combination antiretroviral therapy. We also review the treatment trials of chronic hepatitis C in HIV co-infected individuals with DAAs and compare them to trials in the HCV mono-infected. There is convincing evidence that HIV co-infection no longer diminishes the response to treatment against HCV in the new era of DAA-based therapy. The management of HCV co-infection should therefore become a priority in the care of HIV infected individuals, along with public health efforts to prevent new HCV infections, focusing particularly on specific patient groups at risk, such as men who have sex with men and injecting drug users.

Biomarkers in HCV Infection

Liver-related biomarkers have been developed and validated mainly in patients with chronic hepatitis C for the prediction of liver fibrosis or cirrhosis, which is a final pathway of chronic liver injury. They are noninvasive, traceable, and easy-to-use. Biomarkers provide implications related to screening, diagnosis, treatment, and prognosis of chronic hepatitis. For the improvement of performance and coverage, biomarker panels, imaging biomarkers, and even genetic biomarkers have been developed. With the advancement of genomics and proteomics, earlier and more precise prediction is expected in the near future. In this review, multiple biomarker panels for the estimation of the degree of fibrosis in chronic hepatitis C, biomarkers for the screening and diagnosis of hepatitis C, biomarkers for the treatment of hepatitis C, biomarkers for the prediction of complications related to the chronic hepatitis C, and future perspectives will be summarized.

Host genetic variations are associated with virological response to interferon therapy of chronic HCV in Han Chinese patients

Previous studies have suggested that host genetic polymorphisms may affect virological response to pegylated-interferon and ribavirin (PEG-IFN/ ribavirin) therapy in chronic HCV infection. IL28B and MxA are the most intensively studied genes in Chinese Han population. The current research is to summarize published data and evaluate the overall association of meaningful SNPs in these two genes with virological response to interferon-based therapy. Literature search was performed in online database and a systematic review was conducted based on the search results. Meaningful single nucleotide polymorphisms (SNPs) were summarized and analyzed for odds ratio (OR) and 95% confidence intervals (95% CI). Data manipulation and statistical analyses were performed by using STATA 12.0 and Review Manager version 5.1. Eighteen papers were included for final data analysis. Three SNPs of IL28B and two SNPs of MxA were found to be associated with higher sustained virological response (SVR) to interferon therapy. The ORs and 95% CIs of each variant were: IL28B rs8099917 TT (OR: 4.35, 95% CI: 3.10∼6.12), IL28B rs12979860 CC (OR: 5.37, 95% CI: 3.95∼7.31), IL28B rs7248668 CC (OR: 3.50, 95% CI: 2.30∼5.35), MxA rs2071430 GT (OR: 2.03, 95% CI: 1.31∼3.13), and MxA rs17000900 AC/AA (OR: 1.82, 95% CI: 1.17∼2.83). The genotypes of IL28B rs8099917, rs12979860, rs7248668, MxA rs2071430, and MxA rs17000900 were strong SVR predictors for PEG-IFN/ ribavirin -treated HCV patients in Han Chinese population. Our findings suggest that host genetic variations are associated with virological response to interferon therapy of chronic HCV in Han Chinese patients.

Costs of telaprevir-based triple therapy for hepatitis C: $189,000 per sustained virological response

In registration trials, triple therapy with telaprevir (TVR), pegylated interferon (Peg-IFN), and ribavirin (RBV) achieved sustained virological response (SVR) rates between 64% and 75%, but the clinical effectiveness and economic burdens of this treatment in real-world practice remain to be determined. Records of 147 patients who initiated TVR-based triple therapy at the Mount Sinai Medical Center (May-December 2011) were reviewed. Direct medical costs for pretreatment, on-treatment, and posttreatment care were calculated using data from Medicare reimbursement databases, RED Book, and the Healthcare Cost and Utilization Project database. Costs are presented in 2012 U.S. dollars. SVR (undetectable hepatitis C virus [HCV] RNA 24 weeks after the end of treatment) was determined on an intention-to-treat basis. Cost per SVR was calculated by dividing the median cost by the SVR rate. Median age of the 147 patients was 56 years (interquartile range [IQR] = 51-61), 68% were male, 19% were black, 11% had human immunodeficiency virus/HCV coinfection, 36% had advanced fibrosis/cirrhosis (FIB-4 scores ≥3.25), and 44% achieved an SVR. The total cost of care was $11.56 million. Median cost of care was $83,721 per patient (IQR = $66,652-$98,102). The median cost per SVR was $189,338 (IQR = $150,735-$221,860). Total costs were TVR (61%), IFN (24%), RBV (4%), adverse event management (8%), professional fees (2%), and laboratory tests (1%).

CONCLUSIONS

TVR and Peg-IFN accounted for 85% of costs. Pharmaceutical prices and the low (44%) SVR rate, in this real-world study, were major contributors to the high cost per SVR.

Phylogeography and epidemic history of hepatitis C virus genotype 4 in Africa

HCV genotype 4 is prevalent in many African countries, yet little is known about the genotype׳s epidemic history on the continent. We present a comprehensive study of the molecular epidemiology of genotype 4. To address the deficit of data from the Democratic Republic of the Congo (DRC) we PCR amplified 60 new HCV isolates from the DRC, resulting in 33 core- and 48 NS5B-region sequences. Our data, together with genotype 4 database sequences, were analysed using Bayesian phylogenetic approaches. We find three well-supported intra-genotypic lineages and estimate that the genotype 4 common ancestor existed around 1733 (1650-1805). We show that genotype 4 originated in central Africa and that multiple lineages have been exported to north Africa since ~1850, including subtype 4a which dominates the epidemic in Egypt. We speculate on the causes of the historical intra-continental spread of genotype 4, including population movements during World War 2.

Genotype CC of rs12979860 is providing protection against infection rather than assisting in treatment response for HCV genotype 3a infection

Recent discovery of single-nucleotide polymorphisms located in the upstream region of interleukin-28B (IL28B) has shown association with interferon (IFN) treatment response especially in hepatitis C virus (HCV) genotype 1-infected patients. Pakistan, being the country with second highest prevalence of HCV with predominantly 3a genotype infection, bears a significant disease burden. The present study was conducted to evaluate the effect of rs12979860 genotypes on treatment response in HCV-3a-infected patients. This study shows that the CC genotype is providing protection against infection to HCV. But once infected, the CC genotype patients show viral persistence following IFN therapy. The TT genotype is assisting the 3a patients in viral clearance after IFN treatment. To our knowledge, this is the first study showing rs12979860 genotype association with IFN response in Pakistani HCV-3a-infected patients.

Association of MRC-1 and IL-28B with the treatment outcome of hepatitis C: a case control study

BACKGROUND

The aim of this study was to evaluate whether polymorphisms of the mannose receptor C type 1 (MRC-1) and interleukin 28B (IL-28B) genes are associated with the treatment outcome of patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2, respectively) who are treated with peginterferon plus ribavirin (PEG-IFNα-RBV).

METHODS

We analyzed the association of the patients' sustained viral responses (SVRs) to PEG-IFNα-RBV therapy with 2 single nucleotide polymorphisms (SNPs) in MRC-1 and 3 SNPs in IL-28B. We selected patients infected with either HCV-1 (n = 265) or HCV-2 (n = 195) with or without SVR.

RESULTS

Among the MRC-1 SNPs, rs691005 was found to be associated with SVR in HCV-1-infected patients (P < 0.0001). The IL-28B rs8099917 SNP was found to be associated with SVR in HCV-1- and HCV-2-infected patients (HCV-1, P < 0.0001; HCV-2, P = 0.002), while IL-28B rs955155 and rs10853728 SNPs were found to be associated with SVR in HCV-1-infected patients (P = 0.003) and HCV-2-infected patients (P = 0.02), respectively. We also identified an interaction between MRC-1 rs691005 and IL-28B rs8099917 (P = 0.001). The C-T haplotype was shown to have a positive effect on SVR in HCV-1-infected patients (OR = 1.77, 95% CI = 1.2, 2.62), whereas the T-G haplotype was shown to have a negative effect on SVR in HCV-1-infected patients (OR = 0.28, 95% CI = 0.14, 0.58).

CONCLUSIONS

These results suggest that SNPs of IL-28B and MRC-1 can be used as genetic markers for predicting the outcome of PEG-IFNα-RBV treatment of HCV infections.

Biomarkers of liver fibrosis

Liver fibrosis is the final common pathway for almost all causes of chronic liver injury. Liver fibrosis is now known to be a dynamic process having significant potential for resolution. Therefore, fibrosis prediction is an essential part of the assessment and management of patients with chronic liver disease. As such, there is strong demand for reliable liver biomarkers that provide insight into disease etiology, diagnosis, therapy, and prognosis in lieu of more invasive approaches such as liver biopsy. Current diagnostic strategies range from use of serum biomarkers to more advanced imaging techniques including transient elastography and magnetic resonance imaging. In addition to these modalities, there are other approaches including the use of novel, but yet to be validated, biomarkers. In this chapter, we discuss the biomarkers of liver fibrosis including the use of invasive and noninvasive biomarkers and disease-specific biomarkers in various chronic liver diseases.

Treatment efficacy of pegylated interferon plus ribavirin therapy in chronic hepatitis C patients with mixed genotype 1/2 infection

BACKGROUND AND AIM

The treatment efficacy of patients with mixed hepatitis C virus (HCV) genotype 1/genotype 2 (HCV-1/2) remains unknown. We aimed to elucidate the sustained virological response (SVR) rate in patients with HCV-1/2 infection.

METHODS

One hundred and ten HCV-1/2 patients treated with response-guided peginterferon/ribavirin therapy (24 weeks for patients with a rapid virological response [RVR] and low viral loads; 48 weeks for patients without a RVR or high viral loads) were allocated. Two hundred HCV-1 patients were selected as a historical control. Interleukin-28B (IL-28B) rs8099917 genotype was tested for the association with an SVR.

RESULTS

The rates of RVR, sustained virologic response (SVR), and relapse rate were 71.8%, 87.3%, and 11.1%, respectively. The SVR rate was significantly higher in patients with an abbreviated regimen as compared with those with 48-week regimen (95.5% vs 75.0%, P = 0.002), and both were similar to the HCV-1 historical control. Stepwise logistic regression analysis revealed that lower baseline viral loads were the single factor predictive of an RVR (odds ratio/95% confidence intervals [OR/CI] of 41.62/9.72-178.19, P < 0.001). The achievement of an RVR was the single best factor predictive of an SVR (OR/CI: 7.5/1.33-42.27, P = 0.02). Nevertheless, an abbreviated regimen became the single factor associated with an SVR if treatment regimen was taken into consideration (OR/CI: 11.0/1.25-96.79, P = 0.03). The SVR rate did not differ between patients with rs8099917 TT and TG/GG genotype (91.7% vs 87.5%, P = 0.63).

CONCLUSIONS

The treatment efficacy of patients with HCV-1/2 was satisfactory. The role of IL-28B genetic variants in the population with response-guided therapy was limited.

Nanomedicines in the treatment of hepatitis C virus infection in Asian patients: optimizing use of peginterferon alfa

Asia is endemic for hepatitis C virus (HCV) infection, which is the leading cause of cirrhosis, hepatic decompensation, hepatocellular carcinoma, and liver transplantation worldwide. HCV has six major genotypes and each HCV genotype has its specific geographic distribution. HCV genotypes 1, 2, 3, and 6 are common in Asia. The aim of HCV treatment is to eradicate the virus by effective therapeutic agents; viral clearance is durable after long-term post-treatment follow-up. In most Asian countries, peginterferon alfa (PEG-IFN α) in combination with ribavirin remains the standard of care, and the overall sustained viral response (SVR) rate in Asian HCV patients is higher than that in Western patients. The differences are most significant in patients with HCV genotype 1 (HCV-1) infection, which is attributed to the higher frequency of IFN-responsive or favorable interleukin-28B (IL-28B) genotype in Asian populations than in other ethnic populations. In addition, the introduction of response-guided therapy, where the optimized treatment duration is based on the early viral kinetics during the first 12 weeks of treatment, increases the SVR rate. Recently, telaprevir or boceprevir-based triple therapy was found to further improve the SVR rate in treated and untreated HCV-1 patients and has become the new standard of care in Western and some Asian countries. Many novel direct-acting antiviral agents, either in combination with PEG-IFN α plus ribavirin or used as IFN-free regimens are under active investigation. At the time of this writing, simeprevir and sofosbuvir have been approved in the US. Because the SVR rates in Asian HCV patients receiving PEG-IFN α plus ribavirin therapy are high, health care providers should judiciously determine the clinical usefulness of these novel agents on the basis of treatment duration, anticipated viral responses, patient tolerance, financial burdens, and drug accessibility.

Individualization of chronic hepatitis C treatment according to the host characteristics

Hepatitis C virus (HCV) infection is a global health problem that affects more than 170 million people worldwide. It is a major cause of cirrhosis and hepatocellular carcinoma, making the virus the most common cause of liver failure and transplantation. The standard-of-care treatment for chronic hepatitis C (CHC) has been changed during the last decade and direct acting antiviral drugs have already been used. Besides, understanding of the pathogenesis of CHC has evolved rapidly during the last years and now several host factors are known to affect the natural history and response to treatment. Recent genome-wide association studies have shown the important role of interleukin-28B and inosine triphosphatase in HCV infection. The present review article attempts to summarize the current knowledge on the role of host factors towards individualization of HCV treatment.

Mysterious Linkages Between Hepatitis C Virus Genotypes, Interleukin-28B Genotypes and Viral Clearance- A Meta-Analysis

BACKGROUND

Recent genome wide association studies (GWAS) have shown important roles of single nucleotide polymorphisms (SNP) near region of interleukin B 28 (IL28B) gene in spontaneous and drug-induced clearance of hepatitis C virus (HCV) in genotype 1 HCV infection.

OBJECTIVES

This meta-analysis was designed to determine the world-wide distribution patterns of IL28B genotypes and alleles, and to find possible linkages between IL28B and HCV genotypes.

PATIENTS AND METHODS

Manual and electronic databases were searched. Critical appraisal was performed. According to the results of heterogeneity tests, we used fix/random model for the analysis. The data concerning patients' ethnicity and HCV genotypes were analyzed by using statistical analysis software.

RESULTS

A total of 255 articles were found. After article review and quality assessment, 50 studies, including 18662 patients and 1313 healthy subjects, were analyzed. Presence of HCV genotype 3 versus genotype 1 was significantly associated with a higher frequency of CC genotype and C allele, with an odds ratio (OR) of 1.68 (95% CI: 1.44-1.99) and 1.49 (95% CI: 1.33-1.67), respectively. Prevalence of the rs12979860 CC genotype among genotype 1 HCV infected patients of Asian ethnicity was 69.48% (95% CI: 65.20-73.77), which was significantly higher than its prevalence [33.27% (95% CI: 28.88-37.67)] in the Caucasian genotype 1 HCV infected patients. Prevalence of rs12979860 TT genotype in the African-American genotype 1 HCV infected patients was the highest [36.20% (95% CI: 32.91-39.49)], and significantly different compared to all other ethnicities.

CONCLUSIONS

There were significant linkages between HCV genotypes and IL28B genotypes/alleles. Patients with a favorable IL28B and genotypes 1 and 4 HCV infection stand a better chance to clear HCV in the acute phase.

Individualized therapy for hepatitis C infection: focus on the interleukin-28B polymorphism in directing therapy

Hepatitis C virus—a major global cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma—affects millions of people worldwide. Pegylated interferon (Peg-IFN) and ribavirin (RBV) had been the standard treatment for a decade until availability of the protease inhibitors in 2011. However, current antiviral therapy is still IFN-based and is associated with significant side effects and variable treatment response. Thus, various host and viral factors have been evaluated before and during treatment for the prediction of sustained virologic response to antiviral therapy. In 2009, genome-wide association studies found the single-nucleotide polymorphisms, located near the host interleukin-28B (IL28B) gene that encodes IFN-λ3, to be the best pretreatment predictor of virologic response to Peg-IFN and RBV therapy in chronic hepatitis C genotype 1 patients. Additionally, inosine triphosphatase (ITPA) gene variants were found to be associated with RBV-induced hemolytic anemia, which could affect treatment dose for selected patients. IL28B, ITPA, and other treatment predictors allowed for a potential individualized approach to treat hepatitis C. In the era of increased overall virologic response rates and good tolerability of the rapidly developing non-IFN oral direct-acting antiviral therapy regimens, the need for individualized treatment is likely to diminish. Various predictors of response, including IL28B will likely be of reduced importance in the near future.

Interleukin 28B polymorphisms as predictor of response in hepatitis C virus genotype 2 and 3 infected patients

Single nucleotide polymorphisms near the interleukin 28B (IL-28B) gene have been identified as strong predictors of both spontaneous or Peg-interferon (Peg-IFN) and ribavirin (RBV) induced clearance of hepatitis C virus (HCV). Several studies have shown that, in patients with genotype 1 (GT-1), rs12979860 C/C and rs8099917 T/T substitutions are associated with a more than twofold increase in sustained virological response rate to Peg-IFN and RBV treatment. Although new treatment regimens based on combination of DAA with or without IFN are in the approval phase, until combination regimens with a backbone of Peg-IFN will be used, we can expect that IL28B holds its importance. The clinical relevance of IL28B genotyping in treatment of patients infected with HCV genotype 2 (GT-2) and 3 (GT-3) remains controversial. Therefore, after a careful examination of the available literature, we analyzed the impact of IL28B in GT-2 and -3. Simple size of the studies and GT-2 and GT-3 proportion were discussed. An algorithm for the practical use of IL28B in these patients was suggested at the aim of optimizing treatment.

Viral evolution explains the associations among hepatitis C virus genotype, clinical outcomes, and human genetic variation

Specific human polymorphisms, most commonly found in Central Africa, can predict the success of drug treatment against the hepatitis C virus (HCV), a significant and globally-distributed human pathogen. However, this association is only found for a subset of HCV genotypes. Despite receiving considerable attention in the medical and virological literature, no evolutionary explanation for this curious pattern has been put forward. Here we suggest that the 'drug treatment resistance' phenotype exhibited today by some HCV genotypes evolved hundreds to thousands of years ago in response to human genetic variation local to Central Africa: an adaptation that has since accrued a new function in the era of anti-viral drug treatment. This could represent one of the oldest known examples of viral exaptation at the population level.

Viral hepatitis C gets personal--the value of human genomics to public health

About 180 million people worldwide are chronically infected with hepatitis C virus (HCV), with 3-4 million newly infected each year. Only 15-25% of acute HCV infections clear spontaneously, and the remainder persists as chronic HCV infection. More than 350,000 people die every year from hepatitis C-related liver failure and cancer. There is currently no vaccine and the standard-of-care therapies--peg-interferon alpha (pegIFN) plus ribavirin (RBV)--are expensive and have serious side effects. Also, they may be effective in only 40-50% of patients infected with HCV genotype 1, the most common HCV genotype in the US. Interleukin 28B (IL28B) genotype was recently and convincingly associated with response to pegIFN and RBV therapy. It has emerged as a robust pretreatment predictor of sustained virological response (SVR, i.e. virologic clearance) to pegIFN and RBV as well as to new triple therapy regimens that include a direct-acting antiviral agent with pegIFN and RBV and increase SVR rates as much as 75% in patients infected with HCV genotype 1. Testing for IL28B genotype may contribute to clinical decision-making and could inform clinical guidelines and public health policies.

Polymorphisms in histone deacetylases improve the predictive value of IL-28B for chronic hepatitis C therapy

Histone deacetylases (HDACs) influence many cellular processes, including the modulation of signal transducer and activator of transcription activity (STAT) in response to interferon (IFN). To identify genetic markers that help optimize the IL-28B prediction of chronic hepatitis C (CHC) sustained virological response (SVR), we evaluated 27 single-nucleotide polymorphisms (SNPs) in HDAC1-11. Three SNPs, rs3778216, rs976552 and rs368328 in HDAC2, HDAC3 and HDAC5, respectively, were independently associated with SVR (P<0.05). The addition of these three HDAC's SNPs to the IL-28B predictive model (area under the curve (AUC)=0.630) rendered an important improvement of AUC-receiver operating characteristic value (AUC=0.747, P=0.021). Chi-squared Automatic Interaction Detector (CHAID) analysis denoted the significance of the rs3778216 C/C genotype in identifying a group of good responders despite carrying IL-28B T allele (79.2% of SVR), whereas HDAC5 G allele characterized a subgroup with poor response rate (25.5%). However, HDAC3 rs976552 did not display a relevant role for the hierarchical classification of patients. Variables related to SVR in hepatitis C virus genotype 1 (HCV-1) cohort were the same of those obtained for the overall population. Interestingly, in non-HCV-1 patients (n=56) the HDAC2 C/C genotype was the unique predictive variable related to SVR (AUC=0.733, P<0.007). Thus, these preliminary results suggest the potential usefulness of combined IL-28B and HDAC genotyping for the CHC patients' classification by likelihood of an SVR.

IL-28B polymorphisms and the response to antiviral therapy in HCV genotype 2 and 3 varies by ethnicity: a meta-analysis

Studies of IL-28B genotype in patients with hepatitis C virus (HCV) genotype 2/3 infection have yielded conflicting results. The aim of this meta-analysis was to obtain a pooled odds ratio (OR) of the impact of IL-28B genotype on achieving sustained virologic response (SVR) in patients with HCV genotype 2/3 infection treated with pegIFN and ribavirin. A meta-analysis with a random effects model was performed, and study heterogeneity and publication bias were assessed. Forty-three percent of the Caucasians (11 studies) and 86% of Asians (five studies) had the favourable IL-28B genotype. In Caucasians, the pooled OR of SVR with the favourable IL-28B genotype was 1.36 (95%CI: 0.98-1.88, P = 0.07) in all patients and 1.55 (95%CI: 1.10-2.18, P = 0.01) in patients treated with pegIFN and ribavirin for ≥24 weeks. In Asians, the pooled OR of SVR in patients with the favourable IL-28B genotype was 1.99 (95%CI: 0.94-4.25, P = 0.07). The favourable IL-28B genotype was also significantly associated with rapid virologic response (RVR) in both groups (Caucasians: OR: 1.82, 95%CI: 1.12-2.96, P = 0.02; Asians: 2.39, 95%CI: 1.39-4.11, P = 0.002), as well as the likelihood of an SVR in a subgroup of 350 Caucasian patients without an RVR (OR: 3.29, 95%CI: 1.67-6.51, P = 0.001). The favourable IL-28B genotype is a statistically significant predictor of SVR and RVR in Caucasian patients treated with pegIFN and ribavirin for 24 weeks. In contrast, the favourable IL-28B genotype is associated with RVR, but not SVR in Asian HCV genotype 2 patients.

Challenges in the treatment of chronic hepatitis C in the HIV/HCV-coinfected patient

Hepatitis C virus (HCV) and HIV are common coinfections that convey a shortened lifespan, mostly related to liver disease. Treatment against HCV in the coinfected patient is notoriously more complex and challenging. There are no optimal treatment algorithms for HIV/HCV coinfected patients as efficacy of approved anti-HCV therapies is low with relevant side effects. The use of direct-acting antivirals for anti-HCV therapy has the potential to improve therapeutic efficacy, but also increase side effects and drug-drug interactions. In spite of all of this, the most important and significant fact is that chronic hepatitis C is potentially curable, and the eradication of the HCV infection is a crucial outcome in this population. The establishment of a productive collaboration among the regulatory agencies, the medical community and the pharmaceutical industry could lead to faster access to more effective HCV therapies for the coinfected patient and eventually stop the progression of liver disease in these patients.

Role of interleukin-28B polymorphism as a predictor of sustained virological response in patients with chronic hepatitis C treated with triple therapy: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Chronic hepatitis C represents an important health problem. The aim of our meta-analysis was to establish the role of reference single nucleotide (rs) 12979860 allele of interleukin-28B (IL28B) CC versus CT+TT genotype (the most researched allele of IL28B) as a predictor of sustained virological response (SVR) in patients with chronic hepatitis C treated with triple therapy.

METHODS

The PubMed, MEDLINE, Lilacs, Scopus, Ovid, EMBASE, Cochrane and Medscape databases as well as abstract books from important gastroenterology and hepatology meetings were searched for all studies published until 15 July 2012 that analysed the relationship between the polymorphism of IL28B and SVR in patients with chronic hepatitis C, genotype 1, treated with pegylated interferon + ribavirin + direct antiviral agents (telaprevir or boceprevir). The following keywords were used: IL28B polymorphism, chronic hepatitis C, sustained virological response, SVR, triple therapy, telaprevir, boceprevir.

RESULTS

Odds ratios (ORs) with 95 % confidence intervals were pooled from five study populations (1,641 cases) using a random-effects model. The SVR rate was significantly higher in patients with the CC genotype of IL28B than in those with non-CC genotypes (CT and TT): OR = 3.91 (95 % CI 2.11-7.28), p < 0.0001. Higher SVR rates were obtained in chronic hepatitis C patients with the CC genotype of IL28B, regardless of their therapeutic status (naïve patients: OR = 3.99 [95 % CI 1.67-9.51], p < 0.0001; and previously treated ones: OR = 2.15 [95 % CI 1.35-3.43], p = 0.001).

CONCLUSION

IL28B polymorphism seems to influence the SVR rate in patients with chronic hepatitis C treated with triple therapy, but further studies are needed to clarify the mechanism and the influence of other factors on the SVR rates.

Profound week 4 interferon responsiveness is mandatory for hepatitis C genotype 1 patients with unfavorable IL-28B genotype

BACKGROUND

Viral kinetics and host interleukin 28B (IL-28B) genotype determine treatment outcome in hepatitis C virus genotype 1 (HCV-1) infection.

OBJECTIVES

We aimed to explore the interplay between interferon responsiveness at treatment week 4 and IL28B genotype in the achievement of a sustained virological response (SVR; undetectable HCV RNA 24-weeks after end-of-treatment).

STUDY DESIGNS

Rs8099917 genotypes were determined in 528 HCV-1 patients with peginterferon/ribavirin. Interferon responsiveness were evaluated by the degree of week 4 viral reduction: <1 log(10) IU/mL, 1-2 logs(10) IU/mL, 2-3 logs(10) IU/mL, 3-4 logs(10) IU/mL and ≥4 logs(10) IU/mL reduction and/or undetectable HCV RNA, respectively.

RESULTS

The SVR rate was significantly higher in patients with great interferon responsiveness at week 4. A great interferon responsiveness was associated with younger age (P < 0.0001), lower body mass index (P = 0.0056), lower aspartate aminotransferase levels (P = 0.0009), higher hemogloblin concentration (P = 0.0033), higher platelet counts (P < 0.0001), male gender (P < 0.0001) and rs809997 TT-genotype (P < 0.0001). Comparing to non-TT genotype patients, TT genotype patients had a significantly higher SVR rate with moderate viral reduction (1-3 logs(10) IU/mL) at week 4 (58.9% vs. 18.2%, P < 0.001), and the SVR rate did not differ between TT/non-TT patients on the extreme ends (<1 or >3 log(10) IU/mL reduction) of week 4 interferon responsiveness. For non-TT genotype carriers who were with <3 logs(10) reduction, none (0/15) could have a complete early virological response and only 10.9% (7/64) of the patients had an SVR.

CONCLUSIONS

More profound interferon responsiveness is mandatory for HCV-1 patients with unfavorable IL-28B genotype.

Stability of hepatitis C virus (HCV) RNA levels among interferon-naïve HIV/HCV-coinfected individuals treated with combination antiretroviral therapy

OBJECTIVES

Infection with hepatitis C virus (HCV) is a major cause of chronic liver disease. High HCV RNA levels have been associated with poor treatment response. This study aimed to examine the natural history of HCV RNA in chronically HCV/HIV-coinfected individuals.

METHODS

Mixed models were used to analyse the natural history of HCV RNA changes over time in HIV-positive patients with chronic HCV infection.

RESULTS

A total of 1541 individuals, predominantly White (91%), male (73%), from southern (35%) and western central Europe (23%) and with HCV genotype 1 (58%), were included in the analysis. The median follow-up time was 5.0 years [interquartile range (IQR) 2.8 to 8.3 years]. Among patients not on combination antiretroviral therapy (cART), HCV RNA levels increased by a mean 27.6% per year [95% confidence interval (CI) 6.1-53.5%; P = 0.0098]. Among patients receiving cART, HCV RNA levels were stable, increasing by a mean 2.6% per year (95% CI -1.1 to 6.5%; P = 0.17). Baseline HCV RNA levels were 25.5% higher (95% CI 8.8 to 39.1%; P = 0.0044) in individuals with HCV genotype 1 compared with HCV genotypes 2, 3 and 4. A 1 log HIV-1 RNA copies/mL increase in HIV RNA was associated with a 10.9% increase (95% CI 2.3 to 20.2%; P = 0.012) in HCV RNA.

CONCLUSIONS

While HCV RNA levels increased significantly in patients prior to receiving cART, among those treated with cART HCV RNA levels remained stable over time.

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.

Distribution of IL28B Genotypes in Iranian Patients with Chronic Hepatitis C and Healthy Individuals

BACKGROUND

IL28B polymorphism is recognized as one of the most prominent predictors of hepatitis C spontaneous and treatment-induced clearance. Interestingly, the favorable genotypes of IL28B are found to be more frequent in Asian ethnicity than Caucasian and African populations, respectively. A few studies reported that there is a mysterious association between the IL28B polymorphism and the hepatitis C virus (HCV) genotype in patients with chronic hepatitis C but they did not give any reason for this phenomenon.

OBJECTIVES

The foremost purpose of this study was to compare the distribution of IL28B genotypes between Iranian healthy individuals and patients with chronic hepatitis C.

PATIENTS AND METHODS

In this study, 921 patients with chronic hepatitis C and 142 healthy individuals were included. The IL28B rs12979860 and rs8099917 polymorphisms were genotyped using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

The frequency of IL28B rs12979860 CC, CT, and TT genotypes in chronic hepatitis C patients was 38%, 48.8%, and 13.2% and in healthy individuals was 43.7%, 48.6%, and 7.7%. Also, the frequency of IL28B rs8099917 TT, GT, and GG genotypes in chronic hepatitis C patients was 58.3%, 37.1%, and 4.6% and in healthy individuals was 64.1%, 32.4% and 3.5%. The differences in the distribution of IL28B rs12979860 and rs8099917 genotypes between patients with chronic hepatitis C and healthy individuals were not statistically significant. When we compared the distribution of IL28B genotypes between the healthy group and the HCV infected patients by HCV genotype, we found 9.8% higher frequency of rs12979860 CC genotype in the healthy individuals than HCV genotype 1 infected patients (P = 0.03) however there was no significant difference in the distribution of rs12979860 genotypes between the healthy and HCV genotype 3 infected groups (P = 0.46).

CONCLUSIONS

It seems that the impact of IL28B polymorphism on the spontaneous clearance of HCV genotype 1 is more prominent than HCV genotype 3 which results in the observation of higher rs12979860 C allele frequency in chronic hepatitis C patients with HCV genotype 3 than HCV genotype 1.