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

Human genetic susceptibility to hepatitis B virus infection

Hepatitis B virus (HBV) infection is still a serious health threat worldwide. The outcomes of HBV infection consist of spontaneous HBV clearance and chronic HBV infection. Multiple factors contribute to the disparity of HBV infection outcomes, including host factors, viral factors and environmental factors. The present review comprehends the current researches mainly focusing on the relationships between genetic determinants, including single nucleotide polymorphisms (SNPs) and haplotypes, and susceptibility of HBV infection, namely chronic (persistent) HBV infection and HBV clearance. A number of determinants in the chromosomes, including mutations in human leukocyte antigens (HLAs), cytokines genes, toll-like receptors (TLRs), and other genes are related to the human susceptibility to HBV infection. Among the above variants, some of those in HLAs have been studied and replicated in multiple-ethnic populations and came to consistent conclusions, while some others are novel and need to be evaluated further.

Economic evaluation of direct-acting antivirals for the treatment of genotype 3 hepatitis C infection in Singapore

BACKGROUND AND AIM

The prohibitively high cost of direct-acting antivirals (DAA) for hepatitis C virus (HCV) infection remains a barrier to treatment access in Singapore. We aimed to evaluate whether DAA as first-line therapy would be cost-effective for genotype 3 (GT3) HCV patients compared with pegylated interferon and ribavirin (PR).

METHODS

A decision tree analysis was used to compare the costs and outcomes of DAA and PR as first-line therapy. Treatment effectiveness, defined as sustained virological response, was assessed using a retrospective cohort of treated GT3 HCV patients. Direct medical costs were estimated from the payer's perspective using billing information. We obtained health utilities from published literature. We performed extensive one-way sensitivity analyses and probabilistic sensitivity analyses to account for uncertainties regarding the model parameters.

RESULTS

In base case analysis, first-line therapy with DAA and PR yielded quality-adjusted life years (QALYs) of 0.69 and 0.62 at a cost of USD 54 634 and USD 23 857, respectively. The resultant incremental cost-effectiveness ratio (ICER) (USD 449 232/QALY) exceeded the willingness-to-pay threshold (USD 53 302/QALY). The ICER was robust for uncertainties regarding the model parameters. The cost of DAA is the key factor influencing the cost-effectiveness of HCV treatment. At current price, DAA as first-line therapy is not cost-effective compared with PR, with or without consideration of retreatment. Threshold analysis suggested that DAA can be cost-effective if it costs less than USD 17 002 for a 12-week treatment course.

CONCLUSION

At current price, DAA as first-line therapy is not cost-effective compared with PR in GT3 HCV patients in Singapore.

Final Report of Unmet Needs of Interferon-Based Therapy for Chronic Hepatitis C in Korea: Basis for Moving into the Direct-Acting Antiviral Era

Background/Aims

To evaluate the era of direct acting antivirals (DAAs), we must understand the treatment patterns and outcomes of interferon-based therapy for hepatitis C virus (HCV) infection. We aimed to elucidate the treatment rate, factors affecting treatment decisions, and efficacy of interferon-based therapy in a real-world setting.

Methods

This nationwide cohort study included 1,191 newly diagnosed patients with chronic HCV infection at seven tertiary hospitals in South Korea. Subjects were followed retrospectively until March 2015, which was just before the approval of DAA therapy.

Results

In total, 48.2% and 49.3% of the patients had HCV genotypes 1 and 2, respectively. Interferon-based therapy was initiated in 541 patients (45.4%). The major reasons for no treatment included ineligibility (18.9%), concern about adverse events (22.3%), cost (21.5%), and an age >75 years (19.5%). Interferon-based therapy was discontinued (18.5%) mainly due to adverse events (n=66). The intent-to-treat analysis found that the sustained virologic response (SVR) rate was 58.3% in genotype 1 patients and 74.7% in non-genotype 1 patients.

Conclusions

Approximately one-third of newly diagnosed HCV patients in South Korea received interferon-based therapy and showed a suboptimal SVR rate. Diagnosis of patients at younger ages and with a less advanced liver status and reducing the DAA therapy cost may fulfill unmet needs.

Hepatocellular carcinoma or interferon-based therapy history attenuates sofosbuvir/ribavirin for Japanese genotype 2 hepatitis C virus

AIM

To investigate the real-world efficacy and safety of sofosbuvir/ribavirin (SOF/RBV) therapy for Japanese patients with genotype 2 hepatitis C virus (GT2-HCV).

METHODS

A total of 182 patients with GT2-HCV infection who received SOF/RBV therapy for 12 wk at our hospital were enrolled. The patients comprised 122 men and 60 women (age range: 17-84 years; mean age ± SD: 60.1 ± 12.1 years). Relationships between virological response and clinical data were examined by logistic regression analyses.

RESULTS

The proportions of patients with liver cirrhosis and history of hepatocellular carcinoma (HCC) were 29.0% and 17.3%, respectively. The proportion of patients with prior interferon (IFN)-based therapy was 25.6%. SOF/RBV therapy rapidly decreased HCV RNA levels. Several patients required RBV dose reduction because of anemia or fatigue. Four patients discontinued the therapy. The rates of sustained virological response at 12 wk after the end of treatment were 87.9% (intention to treat: 160/182) and 94.1% (per protocol: 159/169). Multivariate analyses showed that history of HCC or IFN-based therapy independently reduced the efficacy of SOF/RBV therapy.

CONCLUSION

SOF/RBV therapy for GT2-HCV is safe, highly tolerated, and effective. History of HCC or IFN-based therapy independently reduces the efficacy of this treatment.

A systematic review and meta-analysis of HCV clearance

While hepatitis C exemplifies the role of host genetics in infectious diseases outcomes, there is no comprehensive overview of polymorphisms influencing spontaneous and/or treatment-induced hepatitis C virus clearance. We performed a systematic review and meta-analysis of host polymorphisms associated with these phenotypes. Literature search was conducted using combinations of keywords in three databases. Studies were reviewed and relevant data systematically extracted for subsequent meta-analyses. Polymorphisms from candidate gene studies were tested in two cohorts of HCV-infected patients with available genomic data. The literature search yielded 8'294 citations, among which 262 studies were selected. In the meta-analysis of 27 HLA studies, the most significant associations with spontaneous hepatitis C virus clearance included DQB1*02, DQB1*03, DRB1*04 and DRB1*11. In the meta-analysis of 16 studies of KIR genes and their HLA-ligands, KIR2DS3 was associated with both spontaneous and treatment-induced clearance, and the HLA-C2 ligand with failure to spontaneously clear the virus. In a pooled analysis of 105 candidate genes and two genome-wide association studies, we observed associations of single nucleotide polymorphisms from nine genes (EIF2AK2, IFNAR2, ITPA, MBL2, MX1, OASL, SPP1, TGFB1, TNK2) with response to interferon-based therapy. Meta-analysis of 141 studies confirmed the association of IFNL3/4 polymorphisms with spontaneous and treatment-induced hepatitis C virus clearance, even in previously underpowered groups, such as hepatitis C virus genotypes 2/3-infected patients. This study may contribute to a better understanding of hepatitis C virus immunopathogenesis and highlights the complex role of host genetics in hepatitis C virus clearance.

Association of IL28B rs8099917 genotype and female sex with spontaneous clearance of hepatitis C virus infection: a Japanese cross-sectional study

Hepatitis C virus (HCV) infection is a serious global health problem. Previous studies have suggested that the interleukin 28B (IL28B) rs8099917 genotype is related to spontaneous clearance of HCV in Caucasian populations. Our objective was to investigate the association of the IL28B rs8099917 genotype with spontaneous clearance of HCV by community-dwelling Japanese. A cross-sectional community-based population study of 993 Japanese residents was conducted. Based on anti-HCV antibody and HCV RNA levels, 50 subjects were assigned to the spontaneous-clearance group, 155 to the chronic-infection group, and 788 to the control group. Logistic regression analysis was done to examine the roles of the IL28B rs8099917 genotype and sex. To analyze the interactions between these factors, an "IL28B rs809991 genotype × sex" interaction term was included in the multivariate analysis. Significantly more subjects in the spontaneous-clearance group than in the chronic-infection group had the favorable IL28B rs8099917 genotype and were female. Multivariate logistic regression analysis extracted the favorable IL28B rs8099917 TT genotype (odds ratio [OR] 9.39; 95% confidence interval [CI], 2.16-40.83, P = 0.003) and female sex (OR, 2.27; 95% CI, 1.16-4.45, P = 0.017) as factors contributing to the spontaneous clearance of HCV. No significant interaction was found between the IL28B rs8099917 genotype and sex (P for interaction = 0.428). Both the favorable IL28B rs8099917 genotype and female sex were associated with the spontaneous clearance of HCV in this Japanese population.

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.

IFNL4 ss469415590 polymorphism contributes to treatment decisions in patients with chronic hepatitis C virus genotype 1b, but not 2a, infection

Recently, the dinucleotide variant ss469415590 (TT/ΔG) in a novel gene, interferon lambda 4 (IFNL4), was identified as a stronger predictor of hepatitis C virus (HCV) clearance in individuals of African ancestry compared with rs12979860. We aimed to determine whether this variant contributes to treatment decisions in a Chinese population. A total of 447 chronic hepatitis C (CHC) patients (including 328 treated with interferon alpha-2b and ribavirin), 129 individuals who had spontaneously cleared HCV (SHC), and 169 healthy controls were retrospectively investigated. ss469415590 genotyping was performed using a mass spectrometry method (SEQUENOM). A higher proportion of SHC individuals carried the TT/TT genotype compared with CHC patients (95.3% vs. 88.8%, P=0.027). In patients with HCV genotype 1b, the ss469415590 variant was independently associated with sustained virologic response (SVR) (odds ratio [OR]=3.247, 95% confidence interval [CI]=1.038-10.159, P=0.043) and on-treatment virological responses, including rapid (RVR), complete early (cEVR), early (EVR), and end-of-treatment (ETVR), with a minimal OR of 3.73. Especially for patients with high viral load (≥4×10(5) IU/ml), ΔG allele carriers had a lower chance of achieving SVR compared with those carrying the TT/TT genotype (7.1% vs. 36.0%, P=0.034, OR [95% CI]=7.24 [1.02-318.45], negative predictive value=92.9%). In patients with HCV genotype 2a, no significant association between the ss154949590 variant and the virological response was identified (P>0.05). Additionally, we found that ss154949590 was in complete linkage disequilibrium with rs12979860. In conclusion, the IFNL4 ss154949590 TT/TT genotype favors spontaneous clearance of HCV. This same variant is associated with treatment-induced clearance in patients with genotype 1b, but not 2a. ss469415590 (or rs12979860) genotyping should be considered for patients with HCV genotype 1b and high viral load when making a choice between standard dual therapy and an IFN-free direct-acting antiviral regimen.

The Role of Polymorphisms Near the IL28B Gene on Response to Peg-Interferon and Ribavirin in Thalassemic Patients With Hepatitis C

BACKGROUND

Hepatitis C Virus (HCV) is the major cause of liver failure in thalassemic patients. In these patients, iron overload and their comorbidities make difficulties during Pegylated-Interferon (PEG-IFN) and Ribavirin (RBV) therapy.

OBJECTIVES

We aimed to assess the impact of polymorphisms near the IL28B gene on virological response in HCV - infected thalassemic patients, who were treated with PEG-IFN and RBV.

PATIENTS AND METHODS

This cross - sectional study was conducted on 143 thalassemic patients with chronic hepatitis C, who were treated with a combination of PEG-IFN and RBV regimen. The rs12979860 and rs8099917 polymorphisms were assessed as the most common polymorphisms near the IL28B gene by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

The rate of sustained virological response (SVR) was significantly lower in thalassemic patients with HCV genotype-1 infection compared to patients with HCV genotype-3 infection. Among baseline predictors, rs12979860 and rs8099917 polymorphisms were found to be the only parameters associated with achievement of SVR in thalassemic patients with HCV genotype-1 infection however, there was no association between these polymorphisms and the rate of SVR in thalassemic patients with HCV genotype-3 infection.

CONCLUSIONS

In HCV genotype-1- infected thalassemic patients with rs12979860 CC genotype and without severe comorbidities, PEG-IFN and RBV combination therapy can be tried yet in those with rs12979860 CT/TT it may be reasonable to treat cases with new direct-acting antivirals.

Performance and Value of IFN-Lambda3 and IFN-Lambda4 Genotyping in Patients with Chronic Hepatitis C (CHC) Genotype 2/3 in a Real World Setting

BACKGROUND

SNPs near the interferon lambda (IFNL) 3 gene are predictors for sustained virological response (SVR) in patients with chronic hepatitis C genotype (GT) 1. In addition, a dinucleotide frame shift in ss469415590 was described, which generates IFNL4. In this study, we compared the role of IFNL4 variants with IFNL3-(rs12979860) and IFNL3-(rs8099917) on response to pegylated (PEG)-IFN and Ribavirin (RBV) in patients with chronic hepatitis C GT2/3.

METHODS

We recruited 1006 patients with chronic hepatitis C and GT2/3 in a large German registry. A treatment with PEG-IFN and Ribavirin was started by 959 patients. We performed genotyping of IFNL3 (rs12979860, n = 726; rs8099917, n = 687) and of IFNL4 (ss469415590; n = 631).

RESULTS

Both preferable IFNL3 genotypes were associated with RVR (both p<0.0001) rather than with SVR (rs12979860: p = 0.251; rs8099917: p = 0.447). Only RVR was linked to SVR in univariate and multivariate analyzes (both p<0.001). Concordance of genotyping in patients with available serum samples and EDTA blood samples (n = 259) was more than 96% for both IFNL3 SNPs. IFNL3-(rs12979860) correlated with IFNL4: 99.2% of patients with IFNL3-(rs12979860)-CC were IFNL4-(ss469415590)-TT/TT. IFNL3-(rs12979860)-CT was linked with IFNL4-(ss469415590)-TT/ΔG (98.0%) and IFNL3-(rs12979860)-TT was associated with IFNL4-(ss469415590)-ΔG/ΔG (97.6%).

CONCLUSION

IFNL3 genotyping from serum was highly efficient and can be used as an alternative if EDTA whole blood is not available. In Caucasian GT2/3 patients genotyping for INFL4-(ss469415590) does not lead to additional information for the decision-making process. Importantly, IFNL3 SNPs were not associated with SVR but with RVR. Even in the era of new direct acting antiviral (DAA) therapies, IFNL3 testing may therefore still be considered for naïve GT2/3 patients to decide if dual Peg-IFN/RBV therapy is an option in resource limited regions.

Update on the treatment of hepatitis C genotypes 2-6

PURPOSE OF REVIEW

The hepatitis C virus remains a global health issue, and the established standard of care has consisted of pegylated interferon alpha in conjunction with ribavirin. However, this regimen is associated with significant side-effects and poor sustained virological responses. The aim of this review is to assess the effects of the direct-acting antivirals upon hepatitis C genotypes 2-6 from publications from the past 18 months.

RECENT FINDINGS

The impact of direct-acting antivirals has already substantially improved treatments for genotypes 2-6, with the size of improvement much less marked for genotype 3. Although still responsive to these agents, genotype 3 has inherent resistance to treatments possibly owing to its effects on host metabolic pathways. These treatments have moved sustained virological responses to the threshold of 90%, with reduced side-effects and shortened courses of treatment and some options for interferon-free therapy. These newer medications are transforming clinical guidelines at a rapid rate, but this will have to be balanced with the impact it places on global health budgets.

SUMMARY

Although direct-acting antivirals are transforming the treatment of all hepatitis C genotypes, ongoing studies will optimize treatment duration and provide interferon-free alternatives.

Efficacy of telaprevir-based therapy for difficult-to-treat patients with genotype 2 chronic hepatitis C in Japan

AIM

This study assessed the efficacy and safety of telaprevir in combination with peginterferon-α-2b (PEG IFN) and ribavirin (RBV), for Japanese difficult-to-treat patients with hepatitis C virus (HCV) genotype 2 who had not achieved sustained virological response (SVR) during prior treatment.

METHODS

In total, 108 relapsed (median age, 59.0 years) and 10 non-responding (median age, 59.0 years) patients with genotype 2 HCV participated. Patients received telaprevir (750 mg, every 8 h) for 12 weeks and PEG IFN/RBV for 24 weeks.

RESULTS

The SVR rates for relapsers and non-responders were 88.0% (95/108) and 50.0% (5/10), respectively. The SVR rates did not differ significantly between patients with rs8099917 TT and non-TT. The SVR rates for relapsers and non-responders with extended rapid viral response (eRVR) were 97.6% (82/84) and 100% (5/5), respectively. On the other hand, the SVR rates for relapsers and non-responders completing the treatment protocol were 98.4% (61/62) and 100% (5/5), respectively. The overall safety profiles of telaprevir-based regimens were similar for Japanese patients with genotype 1 and 2 HCV infection who experienced treatment failure.

CONCLUSION

Telaprevir, in combination with PEG IFN/RBV, provided a high SVR rate for genotype 2 HCV, difficult-to-treat patients who had not achieved SVR during prior IFN-based treatment. The eRVR had a strong influence on the cure rate of telaprevir-based therapy. In addition, the continuation of telaprevir-based treatment for up to 24 weeks was a significant predictor of SVR.

IFNL3 (IL28B) and IFNL4 polymorphisms are associated with treatment response in Thai patients infected with HCV genotype 1, but not with genotypes 3 and 6

Recent studies have shown an association between single nucleotide polymorphisms (SNPs) in the interferon lambda-3 (IFNL3 or IL-28B) and IFNL4 genes and treatment response to hepatitis C virus genotype 1 (HCV-1) infection. The importance of these SNPs for HCV genotype 3 (HCV-3), and particularly HCV genotype 6 (HCV-6), remains to be elucidated. We analyzed a cohort of 225 Thai individuals with chronic HCV infection treated with pegylated-interferon and ribavirin, of whom 69 (30.7%), 114 (50.7%) and 42 (18.6%) patients were infected with HCV-1, HCV-3, and HCV-6, respectively. DNA extracted from blood samples was analyzed for the SNPs rs12979860 and ss469415590. The distribution of CC, CT, and TT genotypes of rs12979860 was 189 (84%), 28 (12.4%) and 8 (3.6%), respectively, while the distribution of TT/TT, ΔG/TT, and ΔG/ΔG genotypes of ss469415590 was 192(85.3%), 28(12.5%), and 5(2.2%), respectively. Significantly lower frequencies of the favorable genotypes CC (for rs12979860) and TT/TT (for ss469415590) were found in the HCV-1 group in comparison with the other groups. The favorable genotypes were associated significantly with rapid and sustained virological response in the HCV-1 group. However, they were only associated with rapid virological response in the HCV-3 and HCV-6 groups. Furthermore, both SNPs were associated equally with the treatment outcome in the HCV-1 group. In contrast, the role of these SNPs in predicting treatment response was attenuated in the HCV-3 and HCV-6 groups. Thus, identification of these SNPs may be useful only in patients with refractory HCV-1 infection.

Response-guided therapy for hepatitis C genotype 2 and 3 in those with HIV coinfection

BACKGROUND

Current guidelines recommend that interferon-based treatment of hepatitis C (HCV) genotype 2 or 3 in those with HIV coinfection should be for 48 weeks, especially if HCV PCR remains positive after 4 weeks of treatment.

AIM

To examine a single-center experience using response-guided therapy (RGT) using pegylated interferon (PegIFN) and weight-based ribavirin (RBV) for treating HCV genotype 2 or 3 in those with HIV coinfection.

METHODS

Electronic medical records were used to identify patients with HCV genotype 2 or 3 HIV coinfection seen at the Toronto General Hospital Immunodeficiency Clinic from February 2003 to December 2012. HCV PCR was tested after every 4 weeks of treatment until it was negative (<50 IU/mL). RGT protocol was as follows: Those with HCV PCR first negative after 4 weeks (VR4) were treated 24 weeks; first negative after 8 weeks (VR8) treated 36 weeks and VR12 treated 48 weeks.

RESULT

Database search identified 35 individuals with HCV genotype 2 or 3. Twelve were excluded. Total 23 patients completed the treatment and were included for data analysis. Eleven of 23 (48 %) achieved VR4 and eleven of 23 (48 %) achieved VR8. Only one individual had detectable viremia to week 12 and required 48 weeks of treatment. The majority (96 %) were successfully treated with <48 weeks of PegIFN-RBV therapy. One hundred percent achieved SVR with a response-guided HCV therapy.

CONCLUSION

The use of response-guided therapy allows therapy to be shortened in the majority of individuals. HCV PCR testing should be performed every 4 weeks during the first 12 weeks of therapy until HCV PCR is negative.

IL-28B polymorphisms correlated with treatment response in HCV-4 mono-infected patients: a meta-analysis

BACKGROUND

The role of interleukin 28B (IL-28B) polymorphisms played in hepatitis C virus (HCV) infection has been gradually explicit, especially in HCV genotype 1, 2 and 3. However, no confirmative conclusion was acquired in genotype 4 HCV patients. Thus we conducted this meta-analysis.

METHODS

We searched the commonly used databases both in English and Chinese. Meta-analysis was performed in fixed/random effects models using STATA 12.0 or R software. Publication bias was examined through Egger's test and Begg's funnel plot.

RESULTS

In total, 11 studies were included in this meta-analysis, encompassing 1284 patients who were mono-infected with HCV-4 and received Peg-interferon (Peg-IFN) plus Ribavirin (Rbv). Around 53.0% patients would achieve sustained virologic response (SVR), 36.6% achieve rapid virologic response (RVR) and 62.4% achieve end of treatment response (ETR). Egyptian patients had a higher rate achieving SVR than non-Egyptian patients (56.3% vs. 47.8%). IL-28B rs12979860 CC genotype not only favored SVR (OR = 3.95, 95%CI = 3.03-5.16), regardless of citizenship, but also favored RVR (OR = 3.82, 95%CI = 2.46-5.95) and ETR (OR = 4.22, 95%CI = 2.81-6.34). IL-28B rs8099917 genotype TT also correlated with SVR (OR = 3.41, 95%CI = 1.92-6.07), but might not with RVR. IL-28B rs12980275 might still correlate with SVR, but warrant more studies to validate.

CONCLUSIONS

The favorable IL-28B rs12979860 genotype is a statistically significant predictor of SVR, RVR and ETR in HCV-4 monoinfected patients treated with Peg-IFN plus Rbv. Rs8099917 might predict SVR but not RVR. Egyptian HCV-4 patients would achieve better outcomes than non-Egyptian patients when treated with standard care.

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.