Association of a single nucleotide polymorphism near the interleukin-28B gene with response to hepatitis C therapy in HIV/hepatitis C virus-coinfected patients

Association between IFN-λ 3 Gene Polymorphisms and Outcome of Treatment with Direct Acting Antivirals in Chronic HCV-Infected Egyptian Patients

Background: Single nucleotide polymorphisms (SNPs) of the interferon lambda 3 (IFN-λ 3) gene are associated with viral clearance and treatment response in chronic hepatitis C virus (HCV) infection. Aim: to assess whether specific IFN-λ 3 gene SNP, known as rs12979860 (C > T), could predict the outcome of treatment with direct acting antivirals (DAAs) among Egyptian patients with chronic HCV genotype 4 infection. Methods: Tetra-primer (ARMS-PCR) and PCR-RFLP methods were used for SNP genotyping in 100 chronic HCV-infected patients and 50 healthy subjects as control group. Results: The CC (wild type) genotype of rs12979860 was identified in 20 patients, 50% of them achieved sustained virological response (SVR). SNP genotype TT was found in 17 patients and only 2 of them (11.76%) were responders. The frequency of CT genotypes was significantly higher in responders than in non-responders (p= .021). In contrast, the frequency of TT genotypes was significantly higher in non-responders (42.85%, p< .001). On univariate and multivariate logistic regression analyses of the significant predictors of SVR, there were six predictive factors (Age, diabetes mellitus, AST, albumin, type of therapy and IFN-λ 3 genotype). Conclusion: The TT genotype and T allele were significantly associated with failure to achieve SVR. However, CT genotype of IFN-λ 3 (rs12979860) may be considered as a predictor for SVR in patients who received DAAs.

CD4 recovery is associated with genetic variation in IFNγ and IL19 genes

Not all HIV-infected patients receiving cART are able to recover optimal CD4-T cell levels despite achieving undetectable viremia. We evaluated the potential association between polymorphisms (SNPs) in cytokines involved in immune response (IL15, IFNγ and IL19) and the failure to achieve optimal CD4 T-cells restoration after cART. For this, we carried out a retrospective study in 412 HIV-infected patients starting cART with CD4<200 cells/μL. These patients were classified as immunological non-responders (INR) if having a CD4 increase (ΔCD4) below 200 cells/μL after two years on successful cART. IL15, IFNγ and IL19 polymorphisms were genotyped using Sequenom's MassARRAY platform. We found 134 INR patients with a median [IQR] ΔCD4 = 133[73-174] cells/μL. In the multivariate analysis adjusted for age, sex, infection route, ethnic origin, hepatitis co-infection and HIV infection length, the AA genotype of the SNP rs2430561 in IFNγ (OR:2.01[1.13-3.56], p = 0.017) and the TT genotype of polymorphism rs2243191 in IL19 (OR:2.58 [1.17-5.68], p = 0.019) showed significant association with the INR status. Our results show that polymorphisms in IFNγ and IL19 genes significantly impacts in the probability of not achieving an optimal immune recovery in HIV-patients starting cART with CD4 T-cells <200 cells/μL. Thus, these SNPs could represent potential predictive markers of the immunodiscordant response.

Real-World Clinical Efficacy and Tolerability of Direct-Acting Antivirals in Hepatitis C Monoinfection Compared to Hepatitis C/Human Immunodeficiency Virus Coinfection in a Community Care Setting

Background/Aims

Limited data exist comparing the safety and efficacy of direct-acting antivirals (DAAs) in hepatitis C virus (HCV) monoinfected and HCV/human immunodeficiency virus (HIV) coinfected patients in the real-world clinic practice setting.

Methods

All HCV monoinfected and HCV/HIV coinfected patients treated with DAAs between January 2014 and October 2017 in community clinic settings were retrospectively analyzed. Pretreatment baseline patient characteristics, treatment efficacy, factors affecting sustained virologic response at 12 weeks (SVR12) after treatment, and adverse reactions were compared between the groups.

Results

A total of 327 patients were included in the study, of which 253 were HCV monoinfected, and 74 were HCV/HIV coinfected. There was a statistically significant difference observed in SVR12 when comparing HCV monoinfection and HCV/HIV coinfection (94% and 84%, respectively, p=0.005). However, there were no significant factors identified as a predictor of a reduced response. The most common adverse effect was fatigue (27%). No significant drug interaction was observed between DAA and antiretroviral therapy. None of the patients discontinued the treatment due to adverse events.

Conclusions

In a real-world setting, DAA regimens have lower SVR12 in HCV/HIV coinfection than in HCV monoinfection. Further studies involving a higher number of HCV/HIV coinfected patients are needed to identify real predictors of a reduced response.

Pharmacogenetics and the treatment of HIV-/HCV-coinfected patients

This review will summarize the role of pharmacogenetics in the natural history of hepatitis C, particularly in patients with HIV/HCV and will take the perspective of pharmacogenetics and its influence on the response to antiviral therapy and the susceptibility to develop adverse effects. This review will also devote a section to host genetics in other clinical situations, such as disease progression and acute HCV infection, which may determine whether treatment of HIV-/HCV-coinfected patients is implemented or deferred.

AIDS Clinical Research in Spain-Large HIV Population, Geniality of Doctors, and Missing Opportunities

The first cases of AIDS in Spain were reported in 1982. Since then over 85,000 persons with AIDS have been cumulated, with 60,000 deaths. Current estimates for people living with HIV are of 145,000, of whom 20% are unaware of it. This explains the still high rate of late HIV presenters. Although the HIV epidemic in Spain was originally driven mostly by injection drug users, since the year 2000 men having sex with men (MSM) account for most new incident HIV cases. Currently, MSM represent over 80% of new yearly HIV diagnoses. In the 80s, a subset of young doctors and nurses working at Internal Medicine hospital wards became deeply engaged in attending HIV-infected persons. Before the introduction of antiretrovirals in the earlier 1990s, diagnosis and treatment of opportunistic infections was their major task. A new wave of infectious diseases specialists was born. Following the wide introduction of triple combination therapy in the late 1990s, drug side effects and antiretroviral resistance led to built a core of highly devoted HIV specialists across the country. Since then, HIV medicine has improved and currently is largely conducted by multidisciplinary teams of health care providers working at hospital-based outclinics, where HIV-positive persons are generally seen every six months. Antiretroviral therapy is currently prescribed to roughly 75,000 persons, almost all attended at clinics belonging to the government health public system. Overall, the impact of HIV/AIDS publications by Spanish teams is the third most important in Europe. HIV research in Spain has classically been funded mostly by national and European public agencies along with pharma companies. Chronologically, some of the major contributions of Spanish HIV research are being in the field of tuberculosis, toxoplasmosis, leishmaniasis, HIV variants including HIV-2, drug resistance, pharmacology, antiretroviral drug-related toxicities, coinfection with viral hepatitis, design and participation in clinical trials with antiretrovirals, immunopathogenesis, ageing, and vaccine development.

IL28B gene polymorphism rs12979860, but not rs8099917, contributes to the occurrence of chronic HCV infection in Uruguayan patients

BACKGROUND

Host single-nucleotide polymorphisms (SNPs) near the interleukin 28B (IL28B) locus are associated with sustained virological response to antiviral therapy and with spontaneous Hepatitis C Virus (HCV) clearance. Prevalence of these SNPs varies depending on ethnicity. The impact of IL28B SNPs in HCV-infected patients is currently unknown in Uruguay. Therefore, the aim of this study was to evaluate and compare the distribution of polymorphisms in the IL28B gene (rs12979860 and rs8099917) among HCV-infected patients and healthy individuals in Uruguay and thus assess their possible association with the establishment of HCV infection.

METHODS

DNA was recovered from 92 non-infected individuals and 78 HCV-infected patients and SNPs were determined by RFLP and allelic discrimination by real-time PCR.

RESULTS

The distribution of rs12979860 genotypes for the infected population was 29.5%-CC, 47.4%-CT and 23.1%-TT and for the control group 45.7%, 42.4% and 11.9%, respectively. Prevalence in both infected and uninfected individuals is similar to that reported in other countries with admixed populations. The distribution of rs8099917 genotypes for the infected population was 57.7%-TT, 27.2%-TG and 14.1%-GG and for the control group 60.9%, 33.7% and 5.4%, respectively. The comparison of rs12979860 genotype distribution between the two populations evidenced a higher prevalence of the favourable genotype (CC) in the uninfected control group (p < 0.05). Additionally, results generated using logistic regression analysis show that individuals carrying rs12979860-TT or CT genotypes have a higher likelihood of developing chronic hepatitis upon infection with HCV, when compared to CC carriers, considering rs8099917 genotype as constant.

CONCLUSION

Patients with HCV infection have a statistically significant lower prevalence of the favourable rs12979860 genotype when compared to uninfected individuals; therefore we can establish that only IL28B rs12979860-CT and TT genotypes seem to contribute to the occurrence of chronic HCV infection in the cohort of Uruguayan population studied. Considering that a trend towards a higher frequency of "good" response genotypes was observed in responder patients, we believe that IL28B rs12979860 genotyping could be a useful tool for predicting different therapies outcome, including in the DAA era.

Both Hepatitis C Virus-Specific T Cell Responses and IL28B rs12979860 Single-Nucleotide Polymorphism Genotype Influence Antihepatitis C Virus Treatment Outcome in Patients with Chronic Hepatitis C

Despite new treatments for hepatitis C virus (HCV) infection, IFNα-based regimens still have clinical relevance in special populations of patients and remain the only therapeutic option for many patients. We sought to elucidate the interplay between two relevant factors (IL28B polymorphism and T cell immune responses) involved in the outcome of this therapy in HCV-infected patients. We evaluated 38 patients infected with HCV genotype 1-17 coinfected with HIV-who were undergoing a full course of pegIFNα/RBV therapy. The interdependence and roles of T cell-mediated immune responses and IL28B rs12979860 single-nucleotide polymorphism genotype as predictors of virological response to anti-HCV treatment in patients with chronic hepatitis C were evaluated using nonparametric tests. Factors associated with rapid virological response (RVR) in univariate analysis were presence of CD4 T cell response against NS3 HCV protein, low baseline HCV-RNA, and IL28B CC genotype. Factors associated with sustained virological response (SVR) in univariate analysis were IL28B CC genotype, low baseline HCV-RNA, and presence of CD4 response against NS2. In the multivariate analysis, low baseline HCV-RNA and NS3-specific CD4 response showed a clear trend toward association with RVR (P = 0.09 and P = 0.07, respectively). Regarding SVR, IL28B CC genotype was the strongest predictor (P = 0.02), with presence of NS2-specific CD4 response showing a clear trend (P = 0.09). HCV-specific T cell response influences the outcome of pegIFNα/RBV therapy regardless of IL28B genotype. HCV-specific T cell responses (adaptive immunity) seem to influence viral clearance both in the short and long term during therapy (RVR and SVR), whereas the influence of the IL28B genotype (innate immunity) may be more relevant to the long-lasting therapeutic effect (SVR).

Viral and host factors associated with outcomes of hepatitis C virus infection (Review)

Hepatitis C virus (HCV) infection is a major health issue globally. Owing to the progress made in host genetics and HCV molecular virology, emerging data have suggested that the natural course and treatment response in patients with HCV infection are largely determined by complex host‑viral interactions. HCV genotype is the most important viral factor predicting the response to pegylated interferon‑α plus ribavirin therapy. The subtype of HCV genotype 1 is the key viral factor that predicts the efficacy of direct‑acting antiviral therapy. HCV genome heterogeneity and baseline viral load are additionally associated with the treatment response. Multiple host genetic variants localized in genes associated with the immune response have been identified as predictors of spontaneous disease course and therapy outcome in chronic HCV. However, most findings from candidate gene association studies have not been proven universal for all investigated populations and independent studies. Previous findings in independent large genome wide association studies confirmed that interferon‑λ3 gene polymorphisms are associated with spontaneous clearance and treatment responsiveness. A polymorphism of the inosine triphosphatase gene has been identified as a protective factor against ribavirin‑induced anemia and dose reductions. Another genetic variant in the patatin‑like phospholipase domain containing 3 genes is associated with hepatic steatosis and fibrosis in patients with HCV. The present review focused on the identified viral and host factors associated with outcomes of patients with HCV, and assessed the involvement of viral and host genetics in the natural history and treatment outcomes of HCV infection. This will provide novel ideas concerning personalized prevention and individualized clinical management.

Hepatitis C virus pharmacogenomics in Latin American populations: implications in the era of direct-acting antivirals

In recent years, great progress has been made in the field of new therapeutic options for hepatitis C virus (HCV) infection. The new direct-acting antiviral agents (DAAs) represent a great hope for millions of chronically infected individuals because their use may lead to excellent cure rates with fewer side effects. In Latin America, the high prevalence of HCV genotype 1 infection and the significant association of Native American ancestry with risk predictive single-nucleotide polymorphisms (SNPs) in IFNL4 and ITPA genes highlight the need to implement new treatment regimens in these populations. However, the universal accessibility to DAAs is still not a reality in the region as their high cost is one of the major, although not the only, limiting factors for their broad implementation. Therefore, under these circumstances, could the assessment of host genetic markers be a useful tool to prioritize DAA treatment until global access to these new drugs can be achieved? This review will summarize the scientific evidences and the potential implications of HCV pharmacogenomics in this rapidly evolving era of anti-HCV drug development.

Targeting IFN-λ: therapeutic implications

INTRODUCTION

Type-III interferons (IFN-λ), the most recently discovered family of IFNs, shares common features with other family members, but also has many distinctive activities. IFN-λ uniquely has a different receptor complex, and a more focused pattern of tissue expression and signaling effects, from other classes of IFNs. Multiple genome-wide association studies (GWAS) and subsequent validation reports suggest a pivotal role for polymorphisms near the IFNL3 gene in hepatitis C clearance and control, as also for several other epithelial cell tropic viruses. Apart from its antiviral activity, IFN-λ possesses anti-tumor, immune-inflammatory and homeostatic functions. The overlapping effects of IFN-λ with type I IFN, with a restricted tissue expression pattern renders IFN-λ an attractive therapeutic target for viral infection, cancer and autoimmune diseases, with limited side effects. Areas covered: This review will summarize the current and future therapeutic opportunities offered by this most recently discovered family of interferons. Expert opinion: Our knowledge on IFN-λ is rapidly expanding. Though there are many remaining questions and challenges that require elucidation, the unique characteristics of IFN-λ increases enthusiasm that multiple therapeutic options will emerge.

APASL consensus statements and recommendation on treatment of hepatitis C

The Asian-Pacific Association for the Study of the Liver (APASL) convened an international working party on the "APASL consensus statements and recommendation on management of hepatitis C" in March, 2015, in order to revise "APASL consensus statements and management algorithms for hepatitis C virus infection (Hepatol Int 6:409-435, 2012)". The working party consisted of expert hepatologists from the Asian-Pacific region gathered at Istanbul Congress Center, Istanbul, Turkey on 13 March 2015. New data were presented, discussed and debated to draft a revision. Participants of the consensus meeting assessed the quality of cited studies. Finalized recommendations on treatment of hepatitis C are presented in this review.

Rate and predictors of treatment failure to all-oral HCV regimens outside clinical trials

BACKGROUND

Cure rates above 90% have been reported in most Phase III clinical trials using distinct all-oral direct-acting antivirals (DAAs) in chronic hepatitis C patients. Preliminary results in real-world patients have confirmed this, although efficacy tends to be lower.

METHODS

All consecutive chronic hepatitis C patients treated with all-oral DAA regimens at three hepatitis clinics in Spain were retrospectively examined. Host and viral factors were tested as predictors of treatment failure.

RESULTS

A total of 363 chronic hepatitis C patients had completed a course of all-oral DAA therapy outside clinical trials up to the end of 2015. All but 14 (4%) patients achieved sustained virological response. There were 10 failures that occurred after 12 weeks of sofosbuvir-ledipasvir, despite 5 of them being on ribavirin. All failures but one were relapses. The only patient with viral breakthrough selected NS5B L159F and NS5A Y93H. In multivariate analyses, only advanced liver fibrosis (Metavir F3-F4) and HIV coinfection were significantly associated with treatment failure. A trend towards lower response was seen for HCV genotype 4.

CONCLUSIONS

Treatment failures outside clinical trials are roughly seen in 4% of chronic hepatitis C patients who complete a course of all-oral DAA therapy, resembling what is seen in registration trials. In our series, outcomes were not significantly influenced by ribavirin addition, IL28B polymorphisms, HCV genotype, high baseline HCV RNA or prior interferon failure. However, advanced liver fibrosis and HIV coinfection were significantly associated with treatment failure. Our findings support that there is still room for individualization of current DAA therapy.

Prevalence of interleukin-28B single nucleotide polymorphism genotypes in patients with hepatitis C infection in Isfahan, Iran

Background:

Hepatitis C infection is one of the most common causes of liver-related morbidity and mortality. Due to limited efficacy and side-effects of treatment, identification of the determinants of response to treatment is an important issue. Nowadays, genotyping of interleukin (IL)-28B is one of the strongest tests used for prediction of sustained virological response. The prevalence of IL28B genotypes varies across different ethnicities. This study presents data on IL28B single nucleotide polymorphism (SNP) (rs12979860) in a group of Iranian hepatitis C virus (HCV)-infected patients in Isfahan.

Materials and Methods:

One hundred patients already diagnosed for hepatitis C enrolled the study. Genomic DNA was extracted from whole blood samples. Specific primers were used to amplify IL28B gene (rs12979860). The rs129679860 SNP was genotyped by real-time polymerase chain reaction using TaqMan^® probes.

Results:

The mean age of patients was 33.16 years (25–42 years). Ninety-nine subjects were male and 1 was female. The frequency of HCV genotypes was as follows: Genotype 3a: 53%, genotype 1a: 42%, genotype 1b: 2%, mixed genotype (1a + 3a): 1% and 2%: Nontypable.

IL28B rs12979860 genotypes were TT in 17 patients (17%), CT in 41 patients (41%), and CC in the remaining 42 patients (42%).

Conclusion:

The prevalence of C allele is much higher in our population study than in African American HCV patients (62.5% and 40% respectively), which can explain better response to treatment in our patients.

Role of HCV-RNA decay and IP-10 levels after 48 hours of standard HCV therapy as predictors of rapid virological response

BACKGROUND AND OBJECTIVES

Rapid virological response (RVR) is a critical end-point in the era of the new direct-acting antiviral agents (DAA). The aim of this study was to evaluate the predictive value in achieving RVR of HCV-RNA load and IP10 after 48 hours of standard anti HCV therapy.

METHODS

HCV mono-infected and HIV/HCV co-infected patients naives to interferon were included. Demographic data, immune-virological HIV-related condition and HCV disease status were recorded before starting treatment. HCV-RNA and IP10 concentrations were also measured 48 hours after first interferon dose. Univariate model, logistic regression and ROC curve were performed for statistical analysis.

RESULTS

Thirty-two patients were enrolled (mean age 49.2 ± 5.6 years): all were treated with pegylated-interferon and ribavirin. Nineteen (59.3%) were HIV/HCV co-infected patients. RVR was reached in 10 patients (31.2%). A decline of more than two log of HCV-RNA after 48 hours of therapy was associated with RVR (P=0.004). A trend was observed between increased IP10 levels at 48 hours and RVR (P=0.08). In a multivariable model only HCV-RNA at 48 hours was associated with RVR (P=0.011). ROC curve analysis for both HCV-RNA at 48 hours and IP-10 at 48 hours showed an area under the curve of 0.87 (95%CI: 0.74-1; P=0.001) with specificity of 72.2% and sensibility of 90%.

CONCLUSION

In HCV treatment-naïve patients HCV-RNA and IP10 determination after 48 hours of interferon and ribavirin may be a worthwhile endpoint to predict RVR and select patients that may not require DAA addition.

HCV F protein amplifies the predictions of IL-28B and CTLA-4 polymorphisms about the susceptibility and outcomes of HCV infection in Southeast China

Cytotoxic T lymphocyte associated antigen-4(CTLA-4) is an inhibitory receptor with great value in the progression of hepatitis C virus (HCV) infection related diseases. To determine the potential associations of IL-28B rs12979860 and CTLA-4 rs231775, rs3087243 and rs5742909 polymorphisms with the generation of HCV F protein, susceptibility and outcomes of HCV infection, a total of 375 healthy controls, 219 HCV spontaneous recovered patients and 600 chronic HCV patients from Southeast China were recruited and genotyped in this study. And the relative mRNA levels of CTLA-4 in T cells were detected. Logistic regression analysis showed that rs231775 A allele was associated with significantly higher rate of spontaneous viral clearance in anti-HCV F antibody negative patients (adjusted OR=0.512, P=0.008), but allele A was related to higher mRNA level of CTLA-4 with the generation of HCV F protein. And rs5742909 T allele added up to the risk of HCV infection chronicity significantly in patients with the presence of HCV F protein (adjusted OR=2.698, P=0.003). Also, the rs5742909 CC genotype, along with the presence of HCV F protein, indicated a significantly higher CTLA-4 level than that in anti-HCV F antibody negative patients. The AG+AA genotype of rs3087243 significantly increased the susceptibility to HCV infection in subjects over 56 years old (adjusted OR=1.595, P=0.011). Genotype-genotype interaction between IL-28B rs12979860 and CTLA-4 rs3087243 was found to be significantly associated with increased susceptibility to HCV infection (adjusted OR=1.509, P=0.005). Haplotype analysis in CTLA-4 also showed significant association with the generation of HCV F protein. All these results indicated the importance of IL-28B and CTLA-4 polymorphisms and their associations with HCV F protein in the risk and chronicity of HCV infection in Chinese Han population in Southeast China.

Hepatitis C virus genetic variability and evolution

Hepatitis C virus (HCV) has infected over 170 million people worldwide and creates a huge disease burden due to chronic, progressive liver disease. HCV is a single-stranded, positive sense, RNA virus, member of the Flaviviridae family. The high error rate of RNA-dependent RNA polymerase and the pressure exerted by the host immune system, has driven the evolution of HCV into 7 different genotypes and more than 67 subtypes. HCV evolves by means of different mechanisms of genetic variation. On the one hand, its high mutation rates generate the production of a large number of different but closely related viral variants during infection, usually referred to as a quasispecies. The great quasispecies variability of HCV has also therapeutic implications since the continuous generation and selection of resistant or fitter variants within the quasispecies spectrum might allow viruses to escape control by antiviral drugs. On the other hand HCV exploits recombination to ensure its survival. This enormous viral diversity together with some host factors has made it difficult to control viral dispersal. Current treatment options involve pegylated interferon-α and ribavirin as dual therapy or in combination with a direct-acting antiviral drug, depending on the country. Despite all the efforts put into antiviral therapy studies, eradication of the virus or the development of a preventive vaccine has been unsuccessful so far. This review focuses on current available data reported to date on the genetic mechanisms driving the molecular evolution of HCV populations and its relation with the antiviral therapies designed to control HCV infection.

IL28B gene polymorphisms in mono- and HIV-coinfected chronic hepatitis C patients

Introduction: Single-nucleotide polymorphisms (SNPs) associated with hepatitis C virus (HCV) clearance were identified near the IL28B gene. Coinfection by the human immunodeficiency virus (HIV) influences the course of HCV contributing to liver damage. Nevertheless, little is known about the relationship between these SNPs and HCV/HIV coinfection. Our aim was to estimate the frequencies of the allelic and genotypic variants of the IL28B polymorphisms rs12979860 (C/T) and rs8099917 (T/G) and their possible association with the establishment of HCV infection.

Methodology: A total of 199 non-infected controls and 230 patients with chronic hepatitis C, including 53 coinfected with HIV, participated in the study. Genotyping consisted of polymerase chain reaction and subsequent analysis of the restriction patterns resulting from exposure to endonucleases.

Results: Among the controls with established results, 47.4% (90/190) exhibited the rs12979860 CC genotype, 43.7 CT, and 8.9% TT, whereas 29.1% (66/227), 51.5%, and 19.4% of the patients exhibited the CC, CT, and TT genotypes, respectively. With respect to rs8099917, 66.8% (133/199) of the controls exhibited the TT genotype, 31.2% TG, and 2.0% GG, whereas 56.1% (129/230), 40.9%, and 3.0% of the patients exhibited the TT, TG, and GG genotypes, respectively.

Conclusion: The frequencies of the rs12979860 C allele and CC genotype and of the rs8099917 T allele and TT genotype were significantly higher among controls compared with patients, thus confirming the suggested protective effect against HCV infection. No significant difference was observed in the genotype and allelic distributions between the mono- and coinfected patients.

Impact of IL28B on the treatment decision in naïve and experienced patients with genotype 1 and 4 chronic hepatitis C in real-life clinical practice: a prospective multicenter cohort

BACKGROUND

The impact of the IL28B genotype on the real-life treatment decisions for patients infected with the hepatitis C virus (HCV) is unknown.

OBJECTIVE

To prospectively analyze the impact of IL28B genotype in HCV genotype 1 (G1)- or 4 (G4)-infected patients using buccal epithelial cell samples in real-life clinical practices.

PATIENTS AND METHODS

From October 2011 to March 2013, 1007 CHC patients were included among 127 French clinical centers.

RESULTS

The IL28B CC, CT, and TT genotype distribution was 252 (25%), 576 (57%), and 177 (18%), respectively. The treatment decisions were recorded and matched with the initial intentions for 433 patients. Multivariate analysis on intention to start treatment showed that patients with HCV G4 were less likely to be intended to be treated than HCV G1 patients (odds ratio [OR]=0.43 [95% CI 0.19-0.97], P=0.04); similarly HIV-HCV coinfected patients were less likely to be intended to be treated than HCV monoinfected patients (OR=0.20 [0.09-0.41], P<.0001); conversely, F3-F4 patients were more likely to be intended to be treated than F0-F2 patients (OR=2.24 [1.29-3.89], P=0.004). Multivariate analysis on final decision to treat showed that Patients with F3-F4 were more likely to be treated than others (OR=2.06 [1.26-3.38], P=0.004). Conversely, although P-values are not significant, patients recruited in public hospitals tended to be less treated (OR=0.65 [0.40-1.04], P=0.069), similarly to HIV-HCV coinfected patients (OR=0.55 [0.28-1.11], P=0.095).

CONCLUSION

Our study showed that the IL28B genotype is used for the management of HCV-infected patients. In the context of future treatments, IL28B genotyping may remain useful if it can be used to develop individualized treatment strategies, identifying patients who can be successfully treated with shorter, simpler, or cheaper regimens.

Hepatitis C virus resistance to interferon therapy: an alarming situation

Hepatitis C virus is presently a major public health problem across the globe. The main objective in treating hepatitis C virus (HCV) infection is to achieve a sustained virological response (SVR). Interferon-α (IFN-α) and pegylated interferon (PegIFN) in combination with Ribavirin (RBV) are the choice of treatment nowadays against chronic hepatitis C. There are several mechanisms evolved by the hepatitis C virus that facilitate the persistence of virus and further lead the patient’s status as non responder. Various factors involved in patient’s lack ofresponse to the therapy include: (1) viral factors, (2) host factors, (3) molecular mechanisms related to the lack of response and (4) social factors. Herein we have made an attempt to summarize all the related predictors of drug resistance in one article so that the future polices can be planned to overcome this obstacle and potential therapies can be designed by considering these factors.

Clinical utility of pharmacogenomics in the management of hepatitis C

Hepatitis C virus (HCV) was identified for the first time more than 20 years ago. Since then, several studies have highlighted the complicated aspects of this viral infection in relation to its worldwide prevalence, its clinical presentation, and its therapeutic response. Recently, two landmark scientific breakthroughs have moved us closer to the successful eradication of chronic HCV infection. First, response rates in treatment-naïve patients and in prior non-responders to pegylated-interferon-α and ribavirin therapy are increasing as a direct consequence of the development of direct-acting antiviral drugs. Secondly, the discovery of single-nucleotide polymorphisms near the interleukin 28B gene significantly related to spontaneous and treatment-induced HCV clearance represents a milestone in the HCV therapeutic landscape. The implementation of this pharmacogenomics finding as a routine test for HCV-infected patients has enhanced our understanding of viral pathogenesis, has encouraged the design of ground-breaking antiviral treatment regimens, and has become useful for pretreatment decision making. Nowadays, interleukin 28B genotyping is considered to be a key diagnostic tool for the management of HCV-infected patients and will maintain its significance for new combination treatment schemes using direct-acting antiviral agents and even in interferon-free regimens. Such pharmacogenomics insights represent a challenge to clinicians, researchers, and health administrators to transform this information into knowledge with the aim of elaborating safer and more effective therapeutic strategies specifically designed for each patient. In conclusion, the individualization of treatment regimens for patients with hepatitis C, that may lead to a universal cure in future years, is becoming a reality due to recent developments in biomarker and genomic medicine. In light of these advances, we review the scientific evidence and clinical implications of recent findings related to host genetic factors in the management of HCV infection.

Apolipoprotein H expression is associated with IL28B genotype and viral clearance in hepatitis C virus infection

BACKGROUND & AIMS

HCV requires host lipid metabolism for replication, and apolipoproteins have been implicated in the response to treatment.

METHODS

We examined plasma apolipoprotein concentrations in three cohorts of patients: mono-infected patients with symptomatic acute hepatitis C (aHCV); those undergoing treatment for chronic hepatitis C (cHCV); and HIV/HCV co-infected patients being treated for their chronic hepatitis C. We also evaluated associations between apolipoproteins and IL28B polymorphisms, a defined genetic determinant of viral clearance.

RESULTS

Plasma apolipoprotein H (ApoH) levels were significantly higher in patients who achieved spontaneous clearance or responded to pegylated-interferon/ribavirin therapy. Strikingly, patients carrying the IL28B rs12979860 CC SNP correlated with the plasma concentration of ApoH in all three cohorts. Both ApoH and IL28B CC SNP were associated with HCV clearance in univariate analysis. Additional multivariate analysis revealed that the association between IL28B and HCV clearance was closely linked to that of Apo H and HCV clearance, suggesting that both belong to the same biological pathway to clearance. The association between IL28B CC SNP and ApoH was not observed in healthy individuals, suggesting that early post-infection events trigger differential ApoH expression in an IL28B allele dependent manner.

CONCLUSIONS

This relationship identifies ApoH as the first induced protein quantitative trait associated with IL28B, and characterises a novel host factor implicated in HCV clearance.

Occasional spontaneous clearance of chronic hepatitis C virus in HIV-infected individuals

The IL28B genotype has been found to have a strong influence on spontaneous clearance of acute HCV both in HCV mono- and HIV/ the HCV co-infected patients. Spontaneous clearance of chronic HCV without HCV treatment is rare. Here, we report on three chronic HCV cases co-infected with HIV with spontaneous clearance of their HCV infection, all with the IL28B CC genotype. These cases were derived from a surveillance of the total HIV/HCV co-infected cohort in Sweden (n =4 66). The estimated frequency of spontaneous clearance of chronic HCV infection in our cohort was calculated to be 0.6-4.7%. Our cases lend some support to the initiation of ART prior to HCV treatment in HIV/HCV co-infected patients. Furthermore, HCV-RNA testing should be recommended immediately before initiation of HCV treatment, to find the subset of HIV/HCV co-infected patients with IL28B CC that may have cleared their chronic infection spontaneously.

HCV RNA viral load is independent from CD4 cell count and plasma HIV RNA viral load in immunocompetent HIV-HCV co-infected patients: a 3-years follow-up study

Background

HCV RNA viral load is an important predictor of sustained virological response and, recently, a significant correlation with liver fibrosis was described. We investigated on possible influence of clinical and viro-immunological variables on HCV viral load in HIV-HCV co-infected patients over a study time of three years (2009-2012).

Methods

We retrospectively enrolled 98 adult patients with a diagnosis of chronic HIV infection in 2009, a diagnosis of chronic HCV infection with a detectable plasma HCV RNA in 2009 and 2012, HCV therapy-naïve or with failed and stopped antiviral treatment before June 2008. The following variables were recorded: age, gender, HCV genotype, IL28B rs12979860 CC genotype, HCV treatment status, advanced liver fibrosis diagnosis, antiretroviral therapy, CD4+ cell count, HCV viral load, HIV RNA (plasma HIV-1 RNA levels were measured from blood samples every three months at least). The correlation was established using linear regression analysis, analysis of variance and Fisher’s exact test. Comparisons between groups were performed using Fisher’s exact test, the independent samples t-test and the t-test for paired data, as appropriate, for continuous variables. A mixed mode (ME) maximum likelihood linear regression model was constructed to evaluate the dependence of HCV viral load.

Results

HCV RNA levels did not change significantly from 2009 to 2012 (from 3924650 ± 5320177 IU/ml to 3085128 ± 3372347 IU/ml, p = 0.13); the CD4+ count increased significantly (from a mean of 576 to a mean of 654, p = 0.003). Using linear regression, a positive correlation was observed for HCV load and genotype 1 (p = 0.002), nonresponder status (p = 0.04) and with interleukin 28B CC allele (p = 0.05). Other studied covariates failed to reach a significant correlation.

Conclusions

The HCV RNA load, a known pretreatment predictor of response to antiviral therapy, was independent of the two main parameters of HIV disease, plasma HIV RNA and CD4 cell count, over an observation time of 3 years in patients with recovered or spontaneously maintained immunocompetence.

Liver fibrosis, host genetic and hepatitis C virus related parameters as predictive factors of response to therapy against hepatitis C virus in HIV/HCV coinfected patients

OBJECTIVE

To establish the role of liver fibrosis as a predictive tool of response to pegylated interferon alpha (Peg-IFN) and ribavirin (RBV) treatment in human immunodeficiency (HIV)/hepatitis C virus (HCV) coinfected patients, in addition to recognized predictive factors (HCV load, HCV genotype, IL-28B polymorphism).

PATIENTS AND METHODS

A sample of 267 HIV/HCV coinfected patients was treated with Peg-IFN and RBV. Predictive factors of rapid (RVR) and sustained (SVR) virological response were analyzed. Independent variables were age, sex, IL28B, -238 TNF-α and -592 IL-10 polymorphisms, HCV genotype, HCV-RNA levels, significant fibrosis or cirrhosis and CD4+ T cell count.

RESULTS

Patients infected by HCV genotype 1 (n = 187) showed RVR and SVR in 12% and 39% of cases, respectively. The parameters associated with RVR were IL28B genotype CC and plasma HCV-RNA levels <600,000 IU/ml. Advanced liver fibrosis was negatively associated with SVR in patients without RVR. A SVR was obtained in 42% of subjects with HCV genotype 4, and the independent factors associated with SVR were IL28B genotype CC and an HCV-RNA <600,000 IU/ml. A SVR was obtained in 66% of patients with HCV genotypes 2/3; in this case, the independent parameter associated with SVR was the absence of significant liver fibrosis. TNF-α and IL-10 polymorphisms were not associated with SVR, although a significantly higher percentage of -238 TNF-α genotype GG was detected in patients with significant liver fibrosis.

CONCLUSIONS

In HIV/HCV coinfected patients with HCV genotypes 1 or 4, RVR, mainly influenced by genotype IL28B and HCV-RNA levels, reliably predicted SVR after 4 weeks of therapy with Peg-IFN plus RBV. In patients infected by HCV genotype 3, an elevated relapse rate compromised the influence of RVR on SVR. Relapses were related to the presence of advanced liver fibrosis. Liver cirrhosis was associated with a -238 TNF-α polymorphism in these patients.

Pharmacogenetics of hepatitis C: transition from interferon-based therapies to direct-acting antiviral agents

Hepatitis C virus (HCV) has emerged as a major viral pandemic over the past two decades, infecting 170 million individuals, which equates to approximately 3% of the world’s population. The prevalence of HCV varies according to geographic region, being highest in developing countries such as Egypt. HCV has a high tendency to induce chronic progressive liver damage in the form of hepatic fibrosis, cirrhosis, or liver cancer. To date, there is no vaccine against HCV infection. Combination therapy comprising PEGylated interferon-alpha and ribavirin has been the standard of care for patients with chronic hepatitis C for more than a decade. However, many patients still do not respond to therapy or develop adverse events. Recently, direct antiviral agents such as protease inhibitors, polymerase inhibitors, or NS5A inhibitors have been used to augment PEGylated interferon and ribavirin, resulting in better efficacy, better tolerance, and a shorter treatment duration. However, most clinical trials have focused on assessing the efficacy and safety of direct antiviral agents in patients with genotype 1, and the response of other HCV genotypes has not been elucidated. Moreover, the prohibitive costs of such triple therapies will limit their use in patients in developing countries where most of the HCV infection exists. Understanding the host and viral factors associated with viral clearance is necessary for individualizing therapy to maximize sustained virologic response rates, prevent progression to liver disease, and increase the overall benefits of therapy with respect to its costs. Genome wide studies have shown significant associations between a set of polymorphisms in the region of the interleukin-28B (IL28B) gene and natural clearance of HCV infection or after PEGylated interferon-alpha and ribavirin treatment with and without direct antiviral agents. This paper synthesizes the recent advances in the pharmacogenetics of HCV infection in the era of triple therapies.

HCV and HIV co-infection: mechanisms and management

HCV and HIV co-infection is associated with accelerated hepatic fibrosis progression and higher rates of liver decompensation and death compared to HCV monoinfection, and liver disease is a leading cause of non-AIDS-related mortality among HIV-infected patients. New insights have revealed multiple mechanisms by which HCV and HIV lead to accelerated disease progression, specifically that HIV infection increases HCV replication, augments HCV-induced hepatic inflammation, increases hepatocyte apoptosis, increases microbial translocation from the gut and leads to an impairment of HCV-specific immune responses. Treatment of HIV with antiretroviral therapy and treatment of HCV have independently been shown to delay the progression of fibrosis and reduce complications from end-stage liver disease among co-infected patients. However, rates of sustained virologic response with PEG-IFN and ribavirin have been significantly inferior among co-infected patients compared with HCV-monoinfected patients, and treatment uptake has remained low given the limited efficacy and tolerability of current HCV regimens. With multiple direct-acting antiviral agents in development to treat HCV, a unique opportunity exists to redefine the treatment paradigm for co-infected patients, which incorporates data on fibrosis stage as well as potential drug interactions with antiretroviral therapy.

Distribution of genetic polymorphisms associated with hepatitis C virus (HCV) antiviral response in a multiethnic and admixed population

The prevalence of genetic polymorphisms identified as predictors of therapeutic-induced hepatitis C virus (HCV) clearance differs among ethnic groups. However, there is a paucity of information about their prevalence in South American populations, whose genetic background is highly admixed. Hence, single-nucleotide polymorphisms rs12979860, rs1127354 and rs7270101 were characterized in 1350 healthy individuals, and ethnicity was assessed in 259 randomly selected samples. The frequency of rs12979860CC, associated to HCV treatment response, and rs1127354nonCC, related to protection against hemolytic anemia, were significantly higher among individuals with maternal and paternal Non-native American haplogroups (64.5% and 24.2%), intermediate among admixed samples (44.1% and 20.4%) and the lowest for individuals with Native American ancestry (30.4% and 6.5%). This is the first systematic study focused on analyzing HCV predictors of antiviral response and ethnicity in South American populations. The characterization of these variants is critical to evaluate the risk-benefit of antiviral treatment according to the patient ancestry in admixed populations.

IFNL4 ss469415590 variant shows similar performance to rs12979860 as predictor of response to treatment against Hepatitis C Virus genotype 1 or 4 in Caucasians

Objectives

The rs12979860 variant, linked to IL28B gene, predicts sustained viral response (SVR) to pegylated-interferon/ribavirin (pegIFN/RBV) therapy in Hepatitis C Virus genotype 1 or 4 (HCV-1/4)-infected patients. Recently, a functional variant, ss469415590, in linkage disequilibrium (LD) with rs12979860, has been discovered. Our objective was to assess the value of ss469415590 to predict SVR to pegIFN/RBV in Caucasian HCV-1/4-infected individuals and to compare its performance with that of rs12979860.

Methods

272 Caucasian HCV-1/4-infected patients who completed a course of pegIFN/RBV were genotyped for both rs12979860 and ss469415590 markers. Logistic regression models including factors with univariate association with SVR and each genetic marker were elaborated. The area under the receiver operating-characteristic curve (AUROC) was calculated for each model and both were compared.

Results

Both markers were in LD (r² = 0.82). For rs12979860, 66 (64.0%) CC versus 56 (33.1%) T allele carriers achieved SVR (Adjusted OR = 4.156, 95%CI = 2.388–7.232, p = 4.647×10⁻⁷). For ss469415590, 66 (66.0%) TT/TT versus 56 (32.5%) –G allele carriers (Adjusted OR = 4.783, 95%CI = 2.714–8.428, p = 6.153×10⁻⁸) achieved SVR. The AUROC of the model including rs12979860 was 0.742 (95%CI = 0.672–0.813) and of that based on ss469415590 was 0.756 (95%CI = 0.687–0.826) (p = 0.780).

Conclusions

The ss469415590 variant shows an equivalent performance to predict SVR to pegIFN/RBV than the rs2979860 in Caucasian HCV-1/4-infected patients.

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.

The role of pharmacogenetics in the treatment of chronic hepatitis C infection

Hepatitis C virus (HCV) chronically infects 170 million people worldwide. Until recently, combination therapy with peginterferon-α (pegIFN) and ribavirin (RBV) has been the standard of care. However, for many patients, especially those infected with the most common HCV genotype 1 (HCV-1), this treatment has resulted in unsatisfactory treatment response rates. Many clinical factors, including pharmacogenetics, influence the treatment response rate. Genetic variation in the interleukin 28B (IL28B) gene is the major determinant of treatment response, a finding that has been replicated in multiple independent cohorts. This review focuses on the association between pharmacogenetics and conventional pegIFN/RBV therapy in patients infected with HCV non-genotype 1; patients reinfected with HCV after liver transplantation; and patients coinfected with HCV and human immunodeficiency virus. We also review the pharmacogenetic data for boceprevir and telaprevir triple therapy in patients with HCV-1 infection, as well as viral genomic polymorphisms and genetic variants that may protect against anemia. Pharmacogenetic information offers a personalized medicine approach to help clinicians and patients make better informed decisions to maximize response and minimize toxicity for the treatment of chronic HCV infection.

Role of IL28B for chronic hepatitis C treatment toward personalized medicine

Genome-wide association studies recently revealed that certain interleukin-28B (IL28B) polymorphisms are strongly associated with responses to pegylated interferon (PEG-IFN) and ribavirin (RBV) therapy in patients chronically infected with hepatitis C virus (HCV) genotype 1, as well as with spontaneous clearance of HCV. Subsequent reports revealed that IL28B genotypes also affect treatment efficacy in chronic infection with other HCV genotypes. Furthermore, there have been several reports that implicate IL28B genotypes in inflammatory status, progression of fibrosis and adverse clinical outcomes in chronic hepatitis C (CHC). Therapy of CHC recently entered a new era with the deployment of direct-acting antivirals. These include nonstructural 3/4A protease inhibitors which have shown promise in combination with PEG-IFN/RBV in several clinical trials. IFN-free therapy is expected to be useful especially in IFN-resistant patients and may become the standard of care in the future. Several clinical trials have revealed an association between IL28B genotype and treatment efficacy in triple therapy or IFN-free regimens. On the other hand the mechanism of the effect of IL28B on HCV infection has not yet been elucidated. Recently, it was shown that the polymorphism of IFN-lambda 4 (IFNL4) is in high linkage disequilibrium with that of near IL28B, and more strongly associated with spontaneous or treatment-induced HCV clearance than IL28B genotypes, especially in individuals of African ancestry. This finding provides new insights into the genetic regulation of HCV clearance and its clinical management. IL28B genotyping will be also useful for personalized CHC treatment in the forthcoming era of direct-acting antivirals.

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.

The cost-effectiveness of improved hepatitis C virus therapies in HIV/hepatitis C virus coinfected patients

OBJECTIVES

To evaluate the effectiveness and cost-effectiveness of strategies to treat hepatitis C virus (HCV) in HIV/HCV coinfected patients in the United States.

PARTICIPANTS

Simulated cohort of HIV/HCV genotype 1 coinfected, noncirrhotic, HCV treatment-naive individuals enrolled in US HIV guideline-concordant care.

DESIGN/INTERVENTIONS

Monte Carlo simulation comparing five strategies: no treatment; dual therapy with pegylated-interferon (PEG) and ribavirin (RBV); 'PEG/RBV trial' in which all patients initiate dual therapy and switch to triple therapy upon failure; 'IL28B triage' in which patients initiate either dual therapy or triple therapy based on their IL28B allele type; and PEG/RBV and telaprevir (TPV) triple therapy. Sensitivity analyses varied efficacies and costs and included a scenario with interferon (IFN)-free therapy.

MAIN MEASURES

Sustained virologic response (SVR), life expectancy, discounted quality-adjusted life expectancy (QALE), lifetime medical costs, and incremental cost-effectiveness ratios (ICERs) in $/quality-adjusted life years (QALY) gained.

RESULTS

'PEG/RBV trial,' 'IL28B triage,' and 'triple therapy' each provided 72% SVR and extended QALE compared with 'dual therapy' by 1.12, 1.14, and 1.15 QALY, respectively. The ICER of 'PEG/RBV trial' compared with 'dual therapy' was $37 500/QALY. 'IL28B triage' and 'triple therapy' provided little benefit compared with 'PEG/RBV trial,' and both had ICERs exceeding $300 000/QALY. In sensitivity analyses, IFN-free treatment attaining 90% SVR had an ICER less than $100 000/QALY compared with 'PEG/RBV trial' when its cost was $109 000 or less (125% of the cost of PEG/RBV/TVR).

CONCLUSION

HCV protease inhibitors are most efficiently used in HIV/HCV coinfection after a trial of PEG/RBV, sparing protease inhibitors for those who attain rapid virologic response and SVR. The cost-effectiveness of IFN-free regimens for HIV/HCV coinfection will depend on the cost of these therapies.

IFNL4 ss469415590 variant is a better predictor than rs12979860 of pegylated interferon-alpha/ribavirin therapy failure in hepatitis C virus/HIV-1 coinfected patients

A new transiently induced region (interferon-λ 4 protein; IFNL4) harbouring a dinucleotide variant ss469415590 (TT or ΔG), upstream of IFNL3 (IL28B), was recently found to be associated with hepatitis C virus (HCV) clearance. To determine the effect of IFLN4 ss469415590 variation on the HCV response to IFN-based therapy in HCV/HIV-1 coinfected patients, ss469415590 was genotyped in a cohort of 207 patients from our clinic. Treatment failure occurred in 77% of minor ΔG-allele carriers versus 48% of noncarriers, indicating that the ΔG allele was strongly associated with treatment failure. Importantly, multivariate logistic analysis revealed that ss469415590 genotype was a better predictor of treatment failure than rs12979860.

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.

Variations at multiple genes improve interleukin 28B genotype predictive capacity for response to therapy against hepatitis C infection

OBJECTIVE

To identify genetic factors that predict sustained virological response (SVR) to pegylated interferon (Peg-IFN)/ribavirin (RBV) in HIV/hepatitis C virus (HCV) genotype 1 or 4-coinfected patients and that enhance the predictive capacity of IL28B genotype in this population.

DESIGN

Prospective cohort study.

SETTING

Five tertiary care centers in Spain.

PATIENTS

Two hundred and five HIV/HCV genotype 1 or 4-coinfected patients who received a complete course of Peg-IFN/RBV for 48 weeks.

MAIN OUTCOME MEASURES

All individuals were genotyped for 144 single-nucleotide polymorphisms (SNPs).

RESULTS

One hundred and sixty-two (79%) patients bore HCV genotype 1. Overall SVR was achieved by 73 (36%) individuals. SNPs at the following genes were associated with SVR: IL28B, low-density lipoprotein receptor (LDLR), transforming growth factor β (TGF-β), aquaporine 2 (AQP-2), very-low-density lipoprotein receptor, Sp110 nuclear body protein, interferon alpha/beta receptor 1, 2'-5'-oligoadenylate synthase 1 and apolipoprotein B. There was a strong synergy between SNPs at IL28B, TGF-β and AQP-2 genes: the number of patients reaching SVR with all three favorable genotypes versus unfavorable genotypes were 22 (78.6%) versus 1 (7.1%) (P = 2.1 × 10). HCV baseline viral load, IL28B, TGF-β, AQP-2 and LDLR haplotypes were independently associated with SVR.

CONCLUSION

A number of genetic factors modify the predictive capacity of IL28B genotype. These can be used to identify HCV genotype 1 or 4-infected patients with a very high or a very low probability to respond to bitherapy with Peg-IFN/RBV. Predictive models based on these factors could be helpful to tailor direct acting antiviral-based therapy.

Variation in IFNL4 genotype and response to interferon-based therapy of hepatitis C in HIV-positive patients with acute and chronic hepatitis C

The IFNL4 ss469415590 polymorphism has recently be shown to better predict treatment response in chronic hepatitis than the IL28B rs12979860 variant. However, no data exist in patients with HIV/hepatitis C virus (HCV) coinfection. Analysing 206 HCV(+)/HIV(+) and 162 HCV(+)/HIV(-) patients, we found that compared with IL28B rs12979860, IFNL4 ss469415590 was strongly associated with response to interferon/ribavirin therapy in HCV(+)/HIV(-) individuals but not in HIV(+)/HCV(+) patients. Thus, effects of the IFNL4 variant may differ in HIV(+) and HIV(-) patients.

Update on HIV/HCV coinfection

Liver disease is currently one of the leading causes of hospitalization and death in HIV-positive individuals. Coinfection with the hepatitis C virus (HCV) is a major contributor to this trend. Besides hepatic damage, which is enhanced in the presence of HIV-associated immunosuppression, HCV may contribute to disease in coinfected individuals by potentiating immune activation and chronic inflammation, which ultimately account for an increased risk of cardiovascular events, kidney disease, and cancers in this population. Fortunately, hepatitis C therapeutics has entered a revolutionary era in which we hope that most patients treated with the new oral direct-acting antivirals (DAA) will be cured. However, many challenges preclude envisioning a prompt elimination of HCV from the coinfected population. Issues that should be addressed include the following: (1) rising incidence of acute hepatitis C in men who have sex with men, and expansion/recrudescence of injection drug use in some settings/regions; (2) adverse drug interactions between antiretrovirals and DAA; and (3) high cost of DAA, which may lead many to defer or fail to access appropriate therapy.

In HIV/hepatitis C virus co-infected patients, higher 25-hydroxyvitamin D concentrations were not related to hepatitis C virus treatment responses but were associated with ritonavir use

BACKGROUND

Among patients with hepatitis C virus (HCV) monoinfection, 25-hydroxyvitamin D [25(OH)D] concentrations are positively associated with a response to peg-interferon/ribavirin. Data on the relation between 25(OH)D concentrations and HCV treatment response in HIV-infected patients are limited.

OBJECTIVE

The objective was to determine whether baseline 25(OH)D concentrations predict virologic response in HIV/HCV co-infected patients and to examine variables associated with 25(OH)D concentrations ≥30 ng/mL.

DESIGN

Data and samples from 144 HCV genotype 1, treatment-naive patients from a completed HCV treatment trial were examined in this retrospective study. Early virologic response (EVR) was defined as ≥2 log10 reduction in HCV RNA and/or HCV RNA <600 IU/mL at week 12 of peg-interferon/ribavirin treatment. Baseline 25(OH)D was measured by liquid chromatography/tandem mass spectrometry.

RESULTS

Compared with the non-EVR control group (n = 68), the EVR group (n = 76) was younger, had fewer cirrhotic subjects, had a higher proportion with the IL28B CC genotype, had a higher albumin concentration, and had a lower HCV viral load at baseline (P ≤ 0.05). The difference in baseline 25(OH)D concentrations between EVR and non-EVR patients was not statistically significant (median: 25 ng/mL compared with 20 ng/mL; P = 0.23). Similar results were found for sustained virologic response (SVR). In multivariable analysis, white and Hispanic race-ethnicity (OR: 6.26; 95% CI: 2.47, 15.88; P = 0.0001) and ritonavir use (OR: 2.68; 95% CI: 1.08, 6.65; P = 0.033) were associated with higher 25(OH)D concentrations (≥30 ng/mL).

CONCLUSION

Baseline 25(OH)D concentrations did not predict EVR or SVR. Because ritonavir impairs the conversion of 25(OH)D to the active metabolite, utilization of 25(OH)D may have been impaired in subjects taking ritonavir. This trial was registered at www.clinicaltrials.gov as NCT00078403.

Pegylated interferon plus ribavirin is suboptimal in IL28B CC carriers without rapid response

OBJECTIVE

Some experts consider that hepatitis C virus (HCV) genotype 1-infected patients harboring IL28B genotype CC should be treated with interferon (Peg-IFN) plus ribavirin (RBV). This study aimed to assess the rate of sustained virological response (SVR) in these subjects, according to whether they achieve rapid virological response (RVR) or not.

METHODS

Prospective cohort study conducted at the Infectious Diseases Units of three Spanish hospitals. 220 treatment-naive, HCV genotype 1-infected patients, 160 of them HIV/HCV-coinfected, who initiated dual therapy with peg-IFN plus RBV were analyzed in an on-treatment approach.

RESULTS

29 (18%) HIV/HCV-coinfected and 14 (23%) HCV-monoinfected (p = 0.44) individuals developed RVR. In the overall population, 32 (39%) patients with IL28B genotype CC versus 11 (8%) bearing genotype non-CC achieved RVR (p < 0.0001). In HCV-monoinfected patients with IL28B genotype CC, SVR was observed in 12 (92%) of those who achieved RVR and in 3 (30%) of those who did not (p = 0.0018). The corresponding figures for HIV/HCV-coinfected individuals were 19 (100%) and 14 (35%), respectively (p < 0.0001).

CONCLUSION

Treatment-naïve HCV-genotype 1-infected patients bearing favorable IL28B genotype should not be treated with dual therapy including Peg-IFN plus RBV if they do not achieve RVR. These subjects clearly represent candidates for more effective therapy with direct-acting antivirals.

SUMMARY

Some experts consider that hepatitis C virus (HCV) genotype 1-infected patients harboring the favorable IL28B genotype CC should be treated with interferon plus ribavirin. However, patients harboring favorable IL28B genotype should not be considered likely responders to the same extent. This prospective cohort study conducted in 220 treatment-naive HCV-infected patients with or without HIV coinfection patients shows that among the IL28B CC carriers, while the subset of those patients who achieve negative plasma HCV-RNA after 4 weeks (rapid virological response, RVR) of dual therapy have a rate of sustained virological response near to 100%, those who do not present RVR show a response rate lower than 40%. Therefore, treatment-naïve HCV-genotype 1-infected patients bearing favorable IL28B genotype who do not achieve RVR should be considered candidates for more effective therapy with direct-acting antivirals like boceprevir or telaprevir.

Variation in both IL28B and KIR2DS3 genes influence pegylated interferon and ribavirin hepatitis C treatment outcome in HIV-1 co-infection

Pegylated-IFN and ribavirin remains the current treatment for chronic HCV infection in patients co-infected with HIV-1, but this regimen has low efficacy rates, particularly for HCV genotype 1/4 infection, has severe side effects and is extremely costly. Therefore, accurate prediction of treatment response is urgently required. We have recently shown that the NK cell gene, KIR2DS3 and a SNP associated with the IL28B gene synergise to increase the risk of chronic infection in primary HCV mono-infected patients. Identification of SNPs associated with the IL28B gene has also proven very powerful for predicting patient response to treatment. Patients co-infected with HIV-1 are of particular concern given they respond less well to HCV treatment, have more side effects and suffer a more rapid liver disease progression. In this study, we examined both IL28B and KIR2DS3 for their ability to predict treatment response in a cohort of HIV-1/HCV co-infected patients attending two treatment centres in Europe. We found that variation in both host genetic risk factors, IL28B and KIR2DS3, was strongly associated with sustained virological response (SVR) to treatment in our co-infected cohort (n = 149). The majority of patients who achieved a rapid virological response (RVR) achieved a SVR. However, it is currently impossible to predict treatment outcome in patients who fail to achieve an RVR. In our cohort, the presence of host genetic risk factors, IL28B-T and KIR2DS3 alleles, resulted in increased odds of treatment failure in these RVR negative patients (n = 88). Our data suggests that testing for host genetic factors will improve predicting treatment responsiveness in the clinical management of co-infected patients, and provides further evidence of the importance of the innate immune system in the immune response to HCV.

IL28B expression depends on a novel TT/-G polymorphism which improves HCV clearance prediction

Approximately 3% of the world population is chronically infected with the hepatitis C virus (HCV), with potential development of cirrhosis and hepatocellular carcinoma. Despite the availability of new antiviral agents, treatment remains suboptimal. Genome-wide association studies (GWAS) identified rs12979860, a polymorphism nearby IL28B, as an important predictor of HCV clearance. We report the identification of a novel TT/-G polymorphism in the CpG region upstream of IL28B, which is a better predictor of HCV clearance than rs12979860. By using peripheral blood mononuclear cells (PBMCs) from individuals carrying different allelic combinations of the TT/-G and rs12979860 polymorphisms, we show that induction of IL28B and IFN-γ-inducible protein 10 (IP-10) mRNA relies on TT/-G, but not rs12979860, making TT/-G the only functional variant identified so far. This novel step in understanding the genetic regulation of IL28B may have important implications for clinical practice, as the use of TT/G genotyping instead of rs12979860 would improve patient management.

The assessment of data mining for the prediction of therapeutic outcome in 3719 Egyptian patients with chronic hepatitis C

INTRODUCTION

Decision-tree analysis; a core component of data mining analysis can build predictive models for the therapeutic outcome to antiviral therapy in chronic hepatitis C virus (HCV) patients.

AIM

To develop a prediction model for the end virological response (ETR) to pegylated interferon PEG-IFN plus ribavirin (RBV) therapy in chronic HCV patients using routine clinical, laboratory, and histopathological data.

PATIENTS AND METHODS

Retrospective initial data (19 attributes) from 3719 Egyptian patients with chronic HCV presumably genotype-4 was assigned to model building using the J48 decision tree-inducing algorithm (Weka implementation of C4.5). All patients received PEG-IFN plus RBV at Cairo-Fatemia Hospital, Cairo, Egypt in the context of the national treatment program. Factors predictive of ETR were explored and patients were classified into seven subgroups according to the different rates of ETR. The universality of the decision-tree model was subjected to a 10-fold cross-internal validation in addition to external validation using an independent dataset collected of 200 chronic HCV patients.

RESULTS

At week 48, overall ETR was 54% according to intention to treat protocol. The decision-tree model included AFP level (<8.08 ng/ml) which was associated with high probability of ETR (73%) followed by stages of fibrosis and Hb levels according to the patients' gender followed by the age of patients.

CONCLUSION

In a decision-tree model for the prediction for antiviral therapy in chronic HCV patients, AFP level was the initial split variable at a cutoff of 8.08 ng/ml. This model could represent a potential tool to identify patients' likelihood of response among difficult-to-treat presumably genotype-4 chronic HCV patients and could support clinical decisions regarding the proper selection of patients for therapy without imposing any additional costs.

'Favourable' IL28B polymorphisms are associated with a marked increase in baseline viral load in hepatitis C virus subtype 3a infection and do not predict a sustained virological response after 24 weeks of therapy

IL28B host genetic make-up is known to play a critical role in the outcome of genotype 1 hepatitis C virus (HCV) infection in the context of both primary infection and therapy. However, the role of IL28B in subtype 3a infection remains unclear, and has not yet been assessed in the UK population where subtype 3a is dominant. In this study, we evaluated the role of the IL28B single-nucleotide polymorphism rs8099917 in 201 patients recruited from two well-defined cohorts (from Nottingham and Oxford), treated with the standard-of-care therapy of pegylated interferon and ribavirin for 24 weeks. We showed that the 'favourable' IL28B gene was associated with a rapid virological response to therapy at 4 weeks (P<0.0001), but not with a sustained virological response to therapy. The median viral load at baseline, before therapy, was markedly increased in people with the 'favourable' IL28B genotype [median viral load for the TT allele, 925,961 IU ml(-1) (range 2200-21,116,965 IU ml(-1)), and for the GT or GG allele, 260,284 IU ml(-1) (range 740-7,560,000 IU ml(-1)); P = 0.0010]. Our results suggest that the host genetic response plays an important role in early viral clearance of subtype 3a virus from the blood. However, significant reservoirs of infection must persist, as viral relapse is common, even in those with the favourable host genotype.

IL28B SNP screening and distribution in the French Canadian population using a rapid PCR-based test

Single nucleotide polymorphisms (SNPs) in the proximity of the interleukin-28B (IL28B) gene can predict spontaneous resolution of hepatitis C virus (HCV) infection and response to interferon therapy. Screening for this polymorphism has become part of the standard criteria for the management of HCV-infected patients, hence the need for a rapid, cost-effective screening method. Here, we describe a rapid PCR-based test to screen for two IL28B SNPs (rs12979860 and rs8099917). We used this test to investigate IL28B polymorphism and prevalence in a cohort of French Canadian injection drug users who are part of a unique population known to have a strong genetic founder effect. This population had lower linkage disequilibrium between the two tested SNPs as compared to other cohorts (|d'| = 0.68, r = 0.59). The special genetic makeup should be considered in the management of HCV-infected patients within that population.