IL28B genotype is not useful for predicting treatment outcome in Asian chronic hepatitis B patients treated with pegylated interferon-α

Interleukin-28B Polymorphisms Predict the Efficacy of Peginterferon Alpha in Patients With Chronic Hepatitis B: A Meta-Analysis

Background: Polyethylene glycol interferon alpha (PEG-IFN-α) is the most frequently used pharmacotherapeutic approach in patients infected with hepatitis B virus (HBV). Numerous studies have reported that interleukin-28B (IL-28B) genetic polymorphisms are related to the therapeutic efficacy of PEG-IFN-α, but the results are inconsistent. The present meta-analysis aimed to analyze the association between IL-28B genetic polymorphisms and the prognosis of patients with chronic hepatitis B (CHB) treated with PEG-IFN-α to inform clinical practice.

Methods: PubMed, EBSCO, and Scopus databases were searched for relevant literature published before February 30, 2021. We calculated the crude odds ratios (ORs) with 95% confidence intervals (CIs) of the cited articles. A total of 2510 patients with CHB treated with PEG-IFN-α in 13 clinical cohort studies were analyzed.

Results: The overall analysis demonstrated a potential association between IL-28B genetic polymorphisms and response to PEG-IFN-α; however, the association was not statistically significant. Furthermore, the subgroup analysis revealed that among patients with HBeAg-negative CHB, the rs12979860 CC genotype and rs8099917 TT genotype were associated with more significant treatment response to PEG-IFN-α (CC vs. non-CC: OR 2.78, 95% CI 1.00–7.76, I² = 83%; TT vs. non-TT: OR 2.16, 95% CI 1.35–3.48, I² = 0%). Among Asian patients with CHB, the rs12979860 CC genotype was associated with a more significant treatment response to PEG-IFN (CC vs. non-CC: OR 1.88, 95% CI 1.18–2.99, I² = 0%).

Conclusion: This meta-analysis revealed that the IL-28B rs12979860 CC genotype and rs8099917 TT genotype indicated a better treatment response than non-CC and non-TT genotypes for PEG-IFN-α in patients with CHB.

Review of Lambda Interferons in Hepatitis B Virus Infection: Outcomes and Therapeutic Strategies

Hepatitis B virus (HBV) chronically infects over 250 million people worldwide and causes nearly 1 million deaths per year due to cirrhosis and liver cancer. Approved treatments for chronic infection include injectable type-I interferons and nucleos(t)ide reverse transcriptase inhibitors. A small minority of patients achieve seroclearance after treatment with type-I interferons, defined as sustained absence of detectable HBV DNA and surface antigen (HBsAg) antigenemia. However, type-I interferons cause significant side effects, are costly, must be administered for months, and most patients have viral rebound or non-response. Nucleos(t)ide reverse transcriptase inhibitors reduce HBV viral load and improve liver-related outcomes, but do not lower HBsAg levels or impart seroclearance. Thus, new therapeutics are urgently needed. Lambda interferons (IFNLs) have been tested as an alternative strategy to stimulate host antiviral pathways to treat HBV infection. IFNLs comprise an evolutionarily conserved innate immune pathway and have cell-type specific activity on hepatocytes, other epithelial cells found at mucosal surfaces, and some immune cells due to restricted cellular expression of the IFNL receptor. This article will review work that examined expression of IFNLs during acute and chronic HBV infection, the impact of IFNLs on HBV replication in vitro and in vivo, the association of polymorphisms in IFNL genes with clinical outcomes, and the therapeutic evaluation of IFNLs for the treatment of chronic HBV infection.

Hepatitis b infection: progress in identifying patients most likely to respond to peginterferon alfa

Introduction: Despite the disadvantage of side effects, pegylated interferon alpha (Peg-IFN α) remains an indispensable agent for chronic hepatitis B (CHB) due to its immunomodulatory effect. The selection of a patient most likely to have a favorable response becomes an essential issue for Peg-IFN α therapy.Areas covered: Recent progress in the prediction of the treatment response to Peg-IFN α.Expert opinion: Before Peg-IFN α therapy, baseline host and viral factors, including female sex, younger age, a high alanine aminotransferase level, HBV genotype A or B, and low viral load, predict a favorable response. In addition, on-treatment viral kinetics of hepatitis B surface antigen (HBsAg), e antigen (HBeAg) and HBV DNA help clinicians determine whether to continue or discontinue Peg-IFN α therapy. The novel HBV markers hepatitis B core-related antigen and HBV RNA have recently been investigated as useful predictors. The limited efficacy of Peg-IFN α monotherapy facilitated the development of new strategies of 'add-on' or 'switch to' Peg-IFN α in patients receiving long-term nucleot(s)ide analog treatment, which may lead to an increase in HBeAg and HBsAg loss. In summary, tailored Peg-IFN α therapeutic strategies based on predictors extended the landscape for CHB treatment.

The impact of IFNL3 genotype on interferon treatment outcome in patients chronically infected with hepatitis B virus: A meta-analysis

BACKGROUND

Polymorphisms near the interferon lambda 3 (IFNL3, also known as IL28B) have been proposed to be associated with interferon (IFN)-induced hepatitis C virus (HCV) clearance, but the impact of IFNL3 variations on the result of IFN-based therapy in chronic hepatitis B (CHB) infection is still poor understood.

METHODS

The purpose of this study was to evaluate the relationship between the IFNL3 polymorphisms and the effectiveness of IFN therapy in patients infected with CHB by means of meta-analysis. PubMed and Embase were utilized to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were analysed together to assess the strength of the association. Subgroup analysis was mainly performed according to HBeAg.

RESULTS

Twelve studies of 1645 CHB patients met the inclusion criteria and were selected in our meta-analysis. One polymorphism, rs12979860, near to the IFNL3 gene had significant association with the response of CHB patients to IFN-based therapy (OR = 2.35, 95% CI: 1.61-3.42 in allelic model). Another polymorphism, rs8099917, had a similar result (OR = 1.57, 95% CI: 1.03-2.40 in dominant model; and OR = 1.88, 95% CI: 1.21-2.90 in allelic model). When stratified by HBeAg, the antiviral outcome was markedly influenced by both two SNPs in HBeAg positive group (for rs12979860, OR = 1.90, 95% CI: 1.31-2.76 and OR = 2.07, 95% CI: 1.26-3.41 in dominant and allelic models respectively; for rs8099917, OR = 1.67, 95% CI: 1.04-2.67 in dominant model and OR = 1.77, 95% CI: 1.10-2.85 in allelic model).

CONCLUSION

We concluded that two polymorphisms (rs12979860 and rs8099917) of IFNL3 may play a crucial role in the IFN-based treatment of CHB, especially in HBeAg positive group.

IL28B rs12979860 T allele protects against CMV disease in liver transplant recipients in the post-prophylaxis and late period

BACKGROUND

Cytomegalovirus (CMV) disease represents a serious complication in liver transplant (OLT) recipients. CMV prophylaxis reduces incidence of CMV disease in the early post-transplant period (on-prophylaxis disease, OPD) but may postpone its manifestation after the completion of prophylaxis. Post-prophylaxis disease (PPD) incidence after prophylaxis cessation may be modified by genetic factors.

METHODS

We analyzed impact of IL28B rs1297986 variants on CMV disease incidence in 743 adult OLT recipients receiving universal prophylaxis.

RESULTS

One hundred and forty-four (19.4%) patients had at least one CMV disease episode. One hundred and two of them (70.8%) had at least one OPD and 36 (25%) patients had PPD, six (4.2%) patients had both. The rate of IL28B T allele carriers was lower in PPD group (38.9%) in comparison with OPD group (66.7%, P = 0.005) and group without CMV disease (61.4%, P = 0.009). The impact of IL28B genotype on the risk of CMV OPD was significant neither in the allelic (TT + CT vs CC, P = 0.32) nor in the recessive model (TT vs CT + CC, P = 0.79). Contrarily, in the PPD group, T allele (TT + CT vs CC) had a protective effect, OR 0.4 (95% CI 0.2-0.8, P = 0.008). Further risk factors of PPD were age <55 years and valganciclovir prophylaxis, whereas the risk factors of OPD were age <55 years, cyclosporine A therapy and pre-transplant CMV serostatus (donor +/recipient -).

CONCLUSIONS

IL28B rs12979860 T allele carriers had a lower risk of CMV PPD.

Genetic Factors That Affect Spontaneous Clearance of Hepatitis C or B Virus, Response to Treatment, and Disease Progression

Hepatitis C virus (HCV) and hepatitis B virus (HBV) infections can lead to cirrhosis, end-stage liver disease, and hepatocellular carcinoma. Over the past decade, studies of individuals infected with these viruses have established genetic associations with the probability of developing a chronic infection, risk of disease progression, and likelihood of treatment response. We review genetic and genomic methods that have been used to study risk of HBV and HCV infection and patient outcomes. For example, genome-wide association studies have linked a region containing the interferon lambda genes to spontaneous and treatment-induced clearance of HCV. We review the genetic variants associated with HCV and HBV infection, and how these variants affect specific expression or activities of their products. Further studies of these variants could provide insights into risk factors for and mechanisms of chronic infection and disease progression, as well as new strategies for treatment.

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

BACKGROUND & AIMS

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

IFNL4 rs368234815 and rs117648444 variants predict off-treatment HBsAg seroclearance in IFN-treated HBeAg-negative chronic hepatitis B patients

BACKGROUND & AIM

Robust baseline predictors of interferon (IFN) response in HBeAg-negative chronic hepatitis B (CHB) patients are not currently available. The recently described rs368234815 TT/ΔG dinucleotide and rs117648444 nonsynonymous P70S polymorphisms in IFN lambda 4 (IFNL4) gene, which are strongly associated with response to IFN in hepatitis C virus (HCV) infection, could be also useful in IFN-treated CHB patients. Here we assessed whether IFNL4 rs368234815 and rs117648444 polymorphisms predict IFN-induced HBsAg clearance in CHB patients.

METHODS

We sequenced the IFNL4 gene on genomic DNA collected from 126 HBeAg-negative CHB patients treated with IFN and followed up for a median of 11 (1-23) years.

RESULTS

The 15-year cumulative probability of HBsAg loss in the 62 carriers of the rs368234815 TT/TT genotype, which abolishes the IFNλ4 protein production, was comparable to that of 19 patients carrying the rs117648444 T allele predicted to produce an impaired IFNλ4-S70 protein (39% vs 42%, P  =  .827). In contrast, these 81 patients, either not producing IFNλ4 or producing an impaired IFNλ4-S70 protein, had a significantly higher 15-year probability of HBsAg loss compared to the 45 subjects predicted to encode only the fully functional IFNλ4-P70 (42% vs 11% P = .003). At multivariate analysis, combination of the rs368234815 and rs117648444 genotypes strongly predicted HBsAg clearance (HR 5.90, 95% CI 1.70-20.9, P = .006) together with pretreatment serum HBV DNA levels (HR 0.57, 95% CI 0.39-0.83, P = .003).

CONCLUSION

IFNL4 rs368234815 and rs117648444 functional variants are worth to be investigated as pretreatment combined predictors of IFN response in HBeAg-negative CHB patients.

Impact of IL28B and OAS gene family polymorphisms on interferon treatment response in Caucasian children chronically infected with hepatitis B virus

AIM

To investigate the impact of IL28B and OAS gene polymorphisms on interferon treatment responses in children with chronic hepatitis B.

METHODS

We enrolled 52 children (between the ages of 4 and 18) with hepatitis B e antigen-negative chronic hepatitis B (CHB), who were treated with pegylated interferon alfa for 48 wk. Single nucleotide polymorphisms in the OAS1 (rs1131476), OAS2 (rs1293747), OAS3 (rs2072136), OASL (rs10849829) and IL28B (rs12979860, rs12980275 and rs8099917) genes were studied to examine their associations with responses to IFN treatment in paediatric patients. We adopted two criteria for the therapeutic response, achieving an hepatitis B virus (HBV) DNA level < 2000 IU/mL and normalization of ALT activity (< 40 IU/L). To perform the analyses, we compared the patients in terms of achieving a partial response (PR) and a complete response (CR) upon measurement at the 24-wk post-treatment follow-up.

RESULTS

The PR and CR rates were 80.8% and 42.3%, respectively. Factors such as age, gender and liver histology had no impact on the type of response (partial or complete). A statistically significant relationship between higher baseline HBV DNA and ALT activity levels and lower rates of PR and CR was shown (P < 0.05). The allele association analysis revealed that only the IL-28B rs12979860 (C vs T) and IL28B rs12980275 (A vs G) markers significantly affected the achievement of PR (P = 0.021, OR = 3.3, 95%CI: 1.2-9.2 and P = 0.014, OR = 3.7, 95%CI: 1.3-10.1, respectively). However, in the genotype analysis, only IL-28B rs12980275 was significantly associated with PR (AA vs AG-GG, P = 0.014, OR = 10.9, 95%CI: 1.3-93.9). The association analysis for CR showed that the TT genotype of IL28B rs12979860 was present only in the no-CR group (P = 0.033) and the AA genotype of OASL rs10849829 was significantly more frequent in the no-CR group (P = 0.044, OR = 0.26, 95%CI: 0.07-0.88). The haplotype analysis revealed significant associations between PR and CR and OAS haplotype (P = 0.0002 and P = 0.001, respectively), but no association with IL28B haplotype was observed.

CONCLUSION

IL28B and OAS polymorphisms are associated with different clinical outcomes in CHB children treated with interferon.

The Role of Interferon Lambda 3 Genetic Polymorphisms in Response to Interferon Therapy in Chronic Hepatitis B Patients: An Updated Meta-Analysis

CONTEXT

Polymorphisms of the interferon lambda 3 (IFNL3) gene have been proposed to be associated with drug-induced clearance of the hepatitis C virus (HCV). However, the role of IFNL3 polymorphisms in the prediction of treatment on chronic hepatitis B (CHB) patients have yielded controversial results. The aim of this study was to clarify the role of IFNL3 polymorphisms (rs12979860, rs8099917, and rs12980275) in the treatment response of CHB patients to interferon (IFN).

EVIDENCE ACQUISITION

EMBASE and PUBMED/MEDLINE were searched to identify relevant studies from January 2009 to March 2015. The search used the keyword "interferon lambda 3" or "IFNL3," combined with the following terms: "interferon therapy," "hepatitis," and "polymorphisms." Odds ratios (ORs) and their 95% confidence intervals (95% CIs) were used to assess the strength of the associations between the polymorphisms and the response to IFN therapy.

RESULTS

Nine studies of 1602 CHB patients receiving IFN treatment were included. Under the random-effects model, patients expressing the variant rs12980275 showed a significantly increased response to IFN therapy (OR = 2.85; 95% CI = 1.14 - 4.60). In the subgroup analyses by antiviral agents, the patients carrying the rs8099917T allele in the IFN-only treatment group showed a significantly increased response to IFN therapy (OR for the dominant model = 2.03; 95% CI = 1.24 - 3.31), whereas those in the mixed treatment group showed a significantly decreased response (OR for the dominant model = 0.30; 95% CI = 0.10 - 0.90).

CONCLUSIONS

This study supports the idea that the IFNL3 gene is an important predictor of the response of CHB patients to IFN therapy.

A randomized clinical trial of peginterferon alpha-2b with or without entecavir in patients with HBeAg-negative chronic hepatitis B: Role of host and viral factors associated with treatment response

Combining peginterferon (PEG-IFN) and a potent nucleoside/nucleotide analogue might improve treatment response in patients with chronic hepatitis B (CHB). The aims of this study were to compare the efficacy of PEG-IFN alpha-2b with or without entecavir in HBeAg-negative CHB and to investigate predictors of response. A total of 126 treatment-naïve patients were randomly assigned to receive monotherapy (n = 63) or combination therapy (n = 63) for 48 weeks. Virological response (VR) was defined as HBV DNA level <2000 IU/mL at week 96. Baseline factors including polymorphisms in the IFNL3 (rs12979860) and HLA-DPA1 (rs3077) genes and on-treatment viral kinetics were determined. At week 48, rates of undetectable HBV DNA were lower in the monotherapy than combination groups, but rates of HBsAg clearance and decline were comparable. At week 96, there was no difference between the corresponding groups regarding virological response (41.3% vs 38.1%, P = 0.856), HBsAg clearance (9.5% vs 4.8%, P = 0.491) and HBsAg decline. Baseline HBsAg level [odds ratio (OR): 3.14 (1.34-7.69), P = 0.012] and rs3077 polymorphism [OR: 2.78 (1.27-6.11), P = 0.011] were independent predictors of response. Patients carried GG genotype of rs3077 with low baseline HBV (<1000 IU/mL) had high probability of achieving VR (76.5%) and HBsAg clearance (29.4%). None of the patients without decrease in HBsAg combined with <2 log10 HBV DNA decline at week 12 achieved a virological response. In conclusion, the combination therapy lead to greater on-treatment HBV DNA suppression but did not improve virological response and HBsAg clearance/decline over monotherapy. Host and viral factors could help optimize decision-making at baseline and during PEG-IFN-based therapy.

Genetic variation in STAT4 predicts response to interferon-α therapy for hepatitis B e antigen-positive chronic hepatitis B

Interferon (IFN)-α is a first-line therapy for chronic hepatitis B (CHB) patients but only initiates a response in a minority of patients. A genetic variant, rs7574865 in STAT4, was recently reported to be associated with risk of developing CHB and hepatitis B virus-related hepatocellular carcinoma. We aimed to determine whether this variant is associated with the response to IFNα treatment for hepatitis B e antigen (HBeAg)-positive CHB patients. We studied 466 HBeAg-positive CHB patients who received either IFNα-2b (n = 224) or pegylated IFNα-2a (n = 242) therapy for 48 weeks and were followed for an additional 24 weeks. The rate of sustained virologic response (SVR), defined as HBeAg seroconversion along with hepatitis B virus DNA level <2000 copies/mL at week 72, was compared among patients with different genotypes of rs7574865. After 48 weeks of treatment and 24 weeks off treatment, the SVR rates in the IFNα-2b and pegylated IFNα-2a therapy groups were 30.4% and 28.9%, respectively. Compared to the rs7574865 GT/TT genotype, the GG genotype (a risk factor of CHB and hepatitis B virus-related hepatocellular carcinoma) was significantly associated with a reduced SVR rate in both patients who received IFNα-2b therapy (21.1% versus 37.2%, P = 0.01) and those who received pegylated IFNα-2a therapy (18.0% versus 41.2%, P = 9.74 × 10(-5) ). In joint analysis of the 466 patients, the GG genotype was associated with an approximately half SVR rate compared to the GT/TT genotype (19.3% versus 39.1%, P = 4.15 × 10(-6) ). A multivariate logistic regression model including rs7574865 and clinical variables showed that rs7574865 was the most significant factor for the prediction of SVR.

CONCLUSION

STAT4 rs7574865 is a reliable predictor of response to IFNα therapy for HBeAg-positive CHB patients and may be used for optimizing the treatment of CHB.

The Correlation Between Interferon Lambda 3 Gene Polymorphisms and Susceptibility to Hepatitis B Virus Infection

BACKGROUND

Cytokines are proteins that mediate innate and adaptive immunity responses. It is hypothesized that interferon lambda 3 (IFNL3) levels can influence the outcome of chronic hepatitis B virus (HBV) infection. Polymorphisms in IFN genes have been associated with response to infection.

OBJECTIVES

This study was carried-out to investigate the association of IFNL3 gene polymorphisms (rs12979860 and rs8099917) with HBV susceptibility, in chronic HBV-infected patients.

PATIENTS AND METHODS

In this case-control study, we determined IFNL3 single nucleotide polymorphisms (SNPs) (rs12979860 and rs8099917) in 221 individuals, with chronic HBV infection, and 200 healthy individuals, who were voluntary blood donors, with negative test for HBV. Alleles and genotypes analyses were performed by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods.

RESULTS

The frequencies of the rs12979860 and rs8099917 genotypes were not significantly different between the HBV-infected and the control groups (CC:CT:TT of 30.3%:48.0%:21.7% vs. 33.0%:49.0%:18.0%, P > 0.05, and GG:GT:TT of 5.8%:39.4%:54.8% vs. 5.0%:41.0%:54.0%, P > 0.05, respectively). Also, the frequencies of the alleles were not significantly different between both groups (C:T of 54.3%:45.7% vs. 57.5%:42.5%, P > 0.05, and G:T of 25.6%:74.4% vs. 25.5%:74.5%, P > 0.05, respectively) and the chronic HBV infection. There were no significant differences between patients, with at least one rs12979860C and or rs8099917T alleles compared to the healthy controls (rs12979860: CT + CC:TT, OR = 1.26, 95%CI = 0.78 - 2.04, P = 0.341 and rs8099917: GT + TT:GG, OR = 1.03, 95%CI = 0.70 - 1.51, P = 0.877, respectively).

CONCLUSIONS

Our study showed no correlation between rs12979860 and rs8099917 SNPs and chronic HBV infection. Further studies, with larger sample sizes and different ethnicities, are necessary to validate our findings.

A Treatment Algorithm for the Management of Chronic Hepatitis B Virus Infection in the United States: 2015 Update

Chronic hepatitis B (CHB) continues to be an important public health problem worldwide, including in the United States. An algorithm for managing CHB was developed by a panel of United States hepatologists in 2004 and subsequently updated in 2006 and 2008. Since 2008, additional data on long-term safety and efficacy of licensed therapies have become available and have better defined therapeutic options for CHB. The evidence indicates that potent antiviral therapy can lead to regression of extensive fibrosis or even cirrhosis, thus potentially altering the natural history of CHB. In addition, appropriate choice of antiviral agent can minimize the risk of resistance. This updated algorithm for managing CHB is based primarily on evidence from the scientific literature. Where data were lacking, the panel relied on clinical experience and consensus expert opinion. The primary aim of antiviral therapy for CHB is durable suppression of serum hepatitis B virus (HBV) DNA to low or undetectable levels. CHB patients who have HBV DNA >2000 IU/mL, elevated alanine aminotransferase level, and any degree of fibrosis should receive antiviral therapy regardless of their hepatitis B e antigen status. CHB patients with HBV DNA >2000 IU/mL and elevated alanine aminotransferase level but no evidence of fibrosis may also be considered for antiviral therapy. Approved antiviral therapies for CHB are interferon alfa-2b, peginterferon alfa-2a, lamivudine, adefovir, entecavir, telbivudine, and tenofovir, although the preferred first-line treatment choices are peginterferon alfa-2a, entecavir, and tenofovir. In determining choice of therapy, considerations include efficacy, safety, rate of resistance, method of administration, duration, and cost.

Effect of IL28B genotype on hepatitis B and C virus infection

Genetic factors play a major role for treatment response and disease progression of chronic hepatitis B (HBV) and C virus (HCV) infection. In 2009 a genome-wide association study (GWAS) identified a single nucleotide polymorphism near the IL28B gene that was associated with treatment-induced viral clearance in chronic HCV infection treated with pegylated interferon-α (PEG-IFN) and ribavirin (RBV). Further, another GWAS found an association between IL28B genotype and spontaneous viral clearance in acute HCV infection. The effect on sustained viral response (SVR) could also be observed in patients receiving a triple-therapy with a direct antiviral agent (DAA) combined with PEG-IFN/RBV. In the era of all-oral interferon-free treatment regimens with the combination of different DAAs-with SVR rates exceeding 90%-the effect of IL28B was blunt. In contrast, in HBV several retrospective studies yielded conflicting results of the association of IL28B with PEG-IFN-induced treatment response.

Association of interferon-gamma inducible protein 10 polymorphism with treatment response to pegylated interferon in HBeAg-positive chronic hepatitis B

BACKGROUND

Interferon-gamma inducible protein 10 (IP-10) plays an important role in the clinical outcome of chronic hepatitis B (CHB). This study aimed to investigate the association between single nucleotide polymorphisms (SNPs) G-201A of the IP-10 gene and treatment response to pegylated interferon (PEG-IFN) in patients with hepatitis B e antigen (HBeAg)-positive CHB.

METHODS

We retrospectively analysed data of patients with HBeAg-positive CHB treated with PEG-IFN for 48 weeks. Virological response (VR) was defined as HBeAg clearance and HBV DNA <2,000 IU/ml at 24 weeks post-treatment. The SNPs G-201A, IFNL3 (rs12979860) and HLA-DPA1 (rs3077) were assessed.

RESULTS

Among 107 patients, VR was achieved in 45 (42.1%) patients. Hepatitis B surface antigen (HBsAg) clearance and decline (<100 IU/ml) were observed in 10 (9.3%) and 22 (20.6%) patients, respectively. The distribution of GG, GA and AA genotypes of G-201A was 76.6%, 19.6% and 3.7%, respectively. Patients with GG genotype, compared to those with non-GG genotype, achieved higher VR rate (48.8% versus 19.2%; P=0.011), decreased HBsAg (25.6% versus 4.0%; P=0.019), and demonstrated a trend in HBsAg clearance (11.0% versus 4%; P=0.294). Patients with GG genotype had more rapid HBsAg decline and higher baseline serum IP-10 levels than those with non-GG genotype (432.2 ±339.0 versus 257.3 ±145.7 pg/ml; P=0.028). SNPs rs12979860 and rs3077 were not associated with VR. Logistic regression analysis suggested that SNP G-201A was an independent predictor of VR (odds ratio 3.81, 95% CI 1.31, 11.12; P=0.014).

CONCLUSIONS

Data from this study demonstrated for the first time that IP-10 polymorphism is independently associated with treatment response to PEG-IFN in patients with HBeAg-positive CHB.

Doubtful Role of IL28B Polymorphism in Occult Hepatitis B Infection

AIMS

To investigate the influence of IL28B polymorphism in occult hepatitis B infection (OBI) and whether IL28B genetic variants are associated with hepatitis B virus (HBV)-specific T-cell responses.

PATIENTS AND METHODS

The rs12979860 IL28B genotype was determined in 34 OBI blood donors, 22 spontaneous HBV resolvers, 36 inactive HBV carriers and 25 seronegative donors. T-cell responses to HBV recombinant proteins were assessed by interferon-γ enzyme-linked immunospot assay.

RESULTS

The frequency of the IL28B CC genotype among OBI patients was similar to that of inactive carriers [41 vs. 39%, respectively, p = 0.961; odds ratio (OR) = 1.10; 95% confidence interval (CI) = 0.42-2.86; p = 0.845]. The IL28B CC genotype was found more frequently in spontaneous resolvers, although the differences were not significant (45 vs. 39%, spontaneous resolvers and inactive carriers, respectively; p = 0.828; OR = 1.31; 95% CI = 0.45-3.83; p = 0.622). HBV-specific T-cell responses were detected in OBIs, and significantly stronger T-cell responses towards hepatitis B envelope antigen were observed in those with the IL28B CC genotype. In spontaneous resolvers and inactive carriers, IL28B CC did not correlate with the magnitude of T-cell responses.

CONCLUSIONS

In OBI donors, IL28B CC correlates with the intensity of HBV-specific T-cell responses. In this study, IL28B CC is not statistically associated with OBI or with HBV clearance, but a larger number of cases is needed before completely ruling out its role in HBV infection.

Frequency of interleukin 28B rs12979860 C>T variants in Filipino patients chronically infected with hepatitis B virus

Hepatitis B virus (HBV) is one of the most prevalent viral infections worldwide. Nearly 400 million individuals are chronic carriers of HBV. The aim of the present study was to determine the frequency of human interleukin 28B (IL28B) variants among treatment naive Filipino patients clinically diagnosed with chronic hepatitis B (CHB), and to compare the IL28B frequency distribution with various ethnic populations. Fifty-seven CHB patients and 43 normal controls were enrolled in this study. Real-time PCR was performed using the TaqMan genotyping assay for IL28B rs12979860. The allelic frequencies among normal controls were 0.94 and 0.06 for the IL28B rs12979860 C and T alleles, respectively. Eighty-eight percent were identified as homozygous for the IL28B C/C genotype and 12% were identified as heterozygous for the IL28B C/T genotype. Among CHB patients, the allelic frequencies were 0.90 for the IL28B C allele and 0.10 for the IL28B T allele. No IL28B T/T genotype was observed between the two groups. No significant difference in the distribution of IL28B genotypes was observed between normal controls and CHB patients. Allelic frequencies of IL28B among Filipinos were similar with other Asian populations but significantly different from Caucasians. The frequency of rs12979860 C>T variants among Filipino CHB patients has not yet been reported. These data provided new insight into the geographical frequency distribution of IL28B variants. Further studies are needed to determine the possible association between IL28B variants and response to pegylated-interferon-α plus ribavirin combination therapy among Filipino patients chronically infected with HBV.

Role of CYP27B1+2838 promoter polymorphism in the treatment of chronic hepatitis B HBeAg negative with PEG-interferon

In HBV-infected patients, the vitamin D deficiency has been related to chronic liver diseases, progression of hepatic fibrosis and poor response to the treatment. The CYP27B1 gene, which encodes the 1-α-hidroxylase and involved in the 1,25-dihydroxyvitamin D synthesis, was recently associated to type-1 diabetes, autoimmune disorders and treatment response in HCV. Then, we aimed to investigate the role of CYP27B1 polymorphisms in HBV treatment with PEG-IFN. We retrospectively enrolled 190 patients with chronic hepatitis B HBeAg negative treated for 48 weeks with PEG-IFN α-2a. We examined the role of rs4646536 CYP27B1 SNP (CYP27B1+2838) according to virological and serological response. Our results showed that the TT genotype of CYP27B1+2838 was significantly prevalent in patients with end-of-therapy virological response (37.6%) vs CT/CC (9.4%) (P < 0.001). Virological relapse was prevalent in patients with CT/CC genotype (12.6%) vs TT genotype (2.1%) (P < 0.001). TT genotype was also related to HBsAg loss (P = 0.004) and anti-HBs appearance (P = 0.002). In the multivariate analysis, the TT genotype resulted to be a good positive predictor of sustained virological response (OR = 5.632, IC = 1.938-16.368, P = 0.001) and serological response (OR = 6.161, IC = 1.856-20.457, P = 0.003). The CYP27B1+2838 polymorphism may be useful as pretreatment factor to selection of patients with higher probability of response to therapy.

Association of IL28B polymorphisms with peginterferon treatment response in Chinese Han patients with HBeAg-positive chronic hepatitis B

AIMS

To investigate whether IL28B polymorphisms could affect the treatment response to peginterferon alpha (PEG-IFN) in chronic hepatitis B (CHB) patients in the Chinese Han population.

METHODS

A total of 212 hepatitis B e antigen (HBeAg)-positive patients treated with PEG-IFN monotherapy were enrolled in this study. Genotype analysis was performed for IL28B rs12980275, rs12979860 and rs8099917 using the MassArray system. Response was defined as cases showing normal aminotransferase (ALT) levels, HBV DNA level < 200 IU/ml and HBeAg seroconversion after 48 weeks of PEG-IFN therapy.

RESULTS

The patients were infected with hepatitis B virus (HBV) genotype B (44.8%) and C (55.2%) with a total response rate of 34.9%. For the three SNPs, there were significant differences between the response (R) and non-response (NR) groups both in allele frequencies and genotype distributions. IL28B genotype was independently associated with R for AA vs. N-AA (OR 2.70, 95% CL 1.21-6.01; P = 0.015) at rs12980275 after adjustment for sex, age, HBV genotype, baseline levels of HBV DNA and ALT. There were similar results for rs12979860 CC vs. N-CC (OR 2.56, 95% CL 1.15-5.67; P = 0.021) and rs8099917 TT vs. N-TT (OR 2.80, 95% CL 1.23-6.39; P = 0.015) respectively. Furthermore, one block formed by rs12980275 and rs12979860 was identified in this study. In multivariate analyses, the most common haplotype A-C was independently associated with high rates of R (OR 2.53, 95% CL 1.20-5.34; P = 0.015).

CONCLUSIONS

Our study suggested that genetic variations in IL28B may play a critical role in PEG-IFN efficacy in HBeAg-positive CHB patients in Han Chinese.

Association of IPS1 polymorphisms with peginterferon efficacy in chronic hepatitis B with HBeAg-positive in the Chinese population

AIMS

To investigate whether IPS1 polymorphisms affect peginterferon alpha (PEG-IFN) efficacy in chronic hepatitis B (CHB) patients using a tag- single nucleotide polymorphism (SNP) approach.

METHODS

A total of 212 hepatitis B e antigen (HBeAg)-positive patients treated with a 48weeks of PEG-IFN monotherapy were enrolled initially and 127 patients were followed for 48weeks posttreatment. Genotype analysis was performed for 10 tag-SNPs in IPS1.

RESULTS

The end of virological response (EVR) rate was 45.8% (97/212) and the sustained virological response (SVR) rate was 45.7% (58/127). Meanwhile, 35.4% (75/212) achieved HBeAg seroconversion at the end of treatment. In a multivariate analysis, the rs2464 CC genotype was independently associated with EVR (OR 2.21, 95% CI 1.23-3.98, P=0.008) and SVR (OR 2.34, 95% CI 1.05-5.20, P=0.037) after adjustment for sex, age, HBV genotype, baseline levels of HBV DNA and ALT. Meanwhile, rs2464 CC genotype were also independently associated with decline of HBsAg levels below 1500IU/mL at 12weeks of treatment (OR 2.52, 95% CI 1.01-6.29, P=0.047). Furthermore, three SNPs were found to be independently associated with HBeAg seroconversion at the end of treatment. (1) The rs2326369 CC genotype was independently associated with no HBeAg seroconversion (OR 0.52, 95% CI 0.29-0.95, P=0.034); (2) The rs6515831 TT genotype was independently associated with HBeAg seroconversion (OR 2.11, 95% CI 1.14-3.90, P=0.017); (3) The rs2464 CC genotype was independently associated with HBeAg seroconversion (OR 2.36, 95% CI 1.26-4.42, P=0.007).

CONCLUSIONS

Polymorphisms in IPS1 are independently associated with treatment response to PEG-IFN among Chinese HBeAg-positive CHB patients.

The relationship between IL-28B polymorphisms and the response to peginterferon alfa-2a monotherapy in anti-HBe-positive patients with chronic HBV infection

The impact of interleukin 28B (IL-28B) on the results of interferon (IFN)-based therapy in patients chronically infected with hepatitis B virus (HBV) is poorly understood. The aim of this study was to evaluate the relationship between IL-28B markers and the response to IFN monotherapy in Polish patients with anti-hepatitis B e (HBe)-positive chronic hepatitis B (CHB). We determined three single-nucleotide polymorphisms (SNPs) of IL-28B (rs12979860, rs12980275, and rs8099917) in 86 patients who were treated with pegylated interferon (PEG-IFN) for 48 weeks. The effectiveness of the therapy was evaluated based on the virological and biochemical response. The primary efficacy parameters were the HBV DNA viral load below 400 IU/ml and 2,000 IU/ml in combination with alanine aminotransferase (ALT) normalization (<40 IU/l), measured 24 weeks after the treatment. Viral load below 400 IU/ml or 2,000 IU/ml with ALT normalization was achieved by 37 % and 46 % of patients, respectively. It has been shown that the distribution of IL-28B genotypes in the dominant genetic model in patients with different therapeutic success differ significantly only for rs12979860. The IL-28B rs12979860 CC genotype was associated with lower treatment success [odds ratio (OR), 0.31; p = 0.025 and OR, 0.37; p = 0.044 for <400 IU/ml HBV DNA with <40 IU/l ALT, and <2,000 IU/ml HBV DNA with <40 IU/l ALT, respectively]. However, in the conditional logistic regression analysis adjusted by factors associated with combined response, rs12979860 was significantly associated only with <400 IU/ml HBV DNA with <40 IU/l ALT (OR, 0.24; p = 0.026). IL-28B polymorphisms have prognostic significance in assessing the treatment effectiveness based on the virological and biochemical response of patients with anti-HBe-positive CHB.

HBsAg loss in patients treated with peginterferon alfa-2a and adefovir is associated with SLC16A9 gene variation and lower plasma carnitine levels

BACKGROUND & AIMS

Achievement of HBsAg loss remains the hallmark of chronic hepatitis B treatment. In order to identify host factors contributing to treatment-induced HBsAg loss, we performed a genome-wide screen of single nucleotide polymorphisms (SNPs) and studied its immunological consequence.

METHODS

Chronic hepatitis B patients (40 HBeAg-positive and 44 HBeAg-negative) treated with peginterferon alfa-2a and adefovir were genotyped for 999,091 SNPs, which were associated with HBsAg loss at week 96 (n = 9). Plasma carnitine levels were measured by tandem-mass spectrometry, and the effect of carnitine on the proliferative capacity of hepatitis B virus (HBV)-specific and non-specific CD8 T cells was studied in vitro.

RESULTS

One polymorphism, rs12356193 located in the SLC16A9 gene, was genome-wide significantly associated with HBsAg loss at week 96 (p = 1.84 × 10(-8)). The previously reported association of rs12356193 with lower carnitine levels was confirmed in our cohort, and baseline carnitine levels were lower in patients with HBsAg loss compared to patients with HBsAg persistence (p = 0.02). Furthermore, we demonstrated that carnitine suppressed HBV-specific CD8 T cell proliferation.

CONCLUSIONS

In chronic hepatitis B patients treated with peginterferon and adefovir, we identified strong associations of SLC16A9 gene variation and carnitine levels with HBsAg loss. Our results further suggest that a lower baseline plasma carnitine level increases the proliferative capacity of CD8 T cells, making patients more susceptible to the immunological effect of this treatment. These novel findings may provide new insight into factors involved in treatment-induced HBsAg loss, and play a role in the prediction of treatment outcome.

Interleukin 28B genetic polymorphism and hepatitis B virus infection

Interleukin (IL) 28B genetic polymorphism is significantly associated with the sustained virological response rate in patients with chronic hepatitis C treated with pegylated interferon-α (PEG-IFN) plus ribavirin and with spontaneous hepatitis C virus clearance. However, a consensus on the relationship between IL28B genetic polymorphism and the favorable outcome of chronic hepatitis B virus infection defined by hepatitis B e antigen seroconversion, and/or hepatitis B surface antigen seroclearance in patients treated with interferon or PEG-IFN has not been reached. Several reports failed to show a positive association, while some studies demonstrated a positive association in certain subject settings. More prospective studies including large cohorts are needed to determine the possible association between IL28B genetic polymorphism and the outcome of interferon or PEG-IFN treatment for chronic hepatitis B.

Peginterferon α in the treatment of chronic hepatitis B

INTRODUCTION

Hepatitis B virus (HBV) infection is a global health problem. Peginterferon α (PEG-IFN), which includes PEG-IFN α-2a (Pegasys) and PEG-IFN α-2b (Peg-Intron), can be used to treat patients with chronic hepatitis B (CHB) infection. A finite duration of PEG-IFN therapy may lead to long-term viral suppression. Clinically, it is important to identify super-responders and null-responders to PEG-IFN due to its substantial side effects.

AREAS COVERED

From the literature review, it is known that PEG-IFN is more effective for hepatitis B e antigen (HBeAg)-positive patients who have high pre-treatment alanine aminotransferase level, lower HBV DNA level and genotype A (vs genotype D), as well as those with more favourable viral predictors, such as precore stop codon or basal core promoter mutants infections in Asian patients and wild-type virus in Caucasian patients. For HBeAg-positive patients and HBeAg-negative patients with genotype D infection, PEG-IFN therapy could be terminated early at week 12 or 24 in primary non-responders defined by the Hepatitis B surface antigen stopping rules. With regard to host factors, single nucleotide polymorphisms of IL28B do not seem to affect the treatment outcomes in Asian patients, but its role in Caucasian patients remains disputed.

EXPERT OPINION

Most of the known predictors need validation by large prospective trials. In addition, we need to identify more baseline predictors for super-responders in order to achieve personalised PEG-IFN treatment for CHB.

Human genes involved in hepatitis B virus infection

Persistent hepatitis B virus (HBV) infection is a significant public health problem because it is a major cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma (HCC). Roughly one-third of the world population has been infected with HBV and there are about 350 million (5%-6%) persistent carriers. HBV causes 80% of all liver cancer cases and is the second most important carcinogen, after smoking tobacco. There is an approximate 90% risk of becoming a persistent carrier following perinatal infection in infants born to e antigen positive carrier mothers and a 30% risk in pre-school children. Only 5%-10% of adults become persistent carriers following infection. Of individuals persistently infected with HBV, 10%-30% will develop liver cirrhosis and HCC. These highly variable outcomes in both clearance rates and disease outcomes in persistently infected individuals cannot be fully explained by differences in immunological, viral or environmental factors. Thus, differences in host genetic factors may affect the natural history of hepatitis B.

Review article: genetic factors that modify the outcome of viral hepatitis

BACKGROUND

Genetic factors can play an important role for treatment response and disease progression in chronic viral hepatitis.

AIM

To review the influence of host genetic factors on the clinical course as well as on treatment response in patients with viral hepatitis.

METHODS

Review of the literature.

RESULTS

A landmark genome-wide association study (GWAS) identified polymorphisms in the IL28B gene on chromosome 19 (19q13.13) associated with response to therapy with pegylated interferon-α (PEG-IFN) and ribavirin (RBV) and spontaneous viral clearance in acute hepatitis C. Furthermore, IL28B genotype is associated with changes of lipid metabolism and insulin resistance. A further GWAS demonstrated that ITPA genetic variants protect HCV genotype 1 patients from RBV-induced anaemia. Another polymorphism in the patatin-like phospholipase domain containing 3 (PNPLA3) is associated with hepatic steatosis. Difficult-to-treat hepatitis C patients homozygous for GG had an up to five-fold lower chance of viral clearance on PEG/RBV than non-GG patients. In chronic hepatitis B patients treated with PEG-IFN several retrospective analyses of IL28B rs12980275 and rs12979860 genotypes yielded conflicting results which can be explained by the heterogeneity between the study populations. Some variants of the HLA-DP locus (HLA-DPA1 A allele and HLA-DPB1) protect against progression of chronic hepatitis B infection.

CONCLUSIONS

The determination of IL28B polymorphisms may be useful to individualise treatment options when using PEG/RBV based therapies for chronic hepatitis C infection. In contrast, so far identified genetic factors play only a minor role in chronic hepatitis B infection.

Systematic review with meta-analysis: do interferon lambda 3 polymorphisms predict the outcome of interferon-therapy in hepatitis B infection?

BACKGROUND

Interferon lambda 3 (IFN-λ3) polymorphisms are the strongest genetic predictor of outcome of hepatitis C virus infection and of response to Pegylated interferon (PegIFN)-based therapy. Whether this holds true for hepatitis B virus (HBV) infection is matter of controversy.

AIM

To review the association between host genomics and spontaneous or interferon-induced clearance of HBV with specific reference to the recently identified interleukin 28B gene now renamed IFN-λ3.

METHODS

A literature search was performed on MEDLINE, EMBASE and Web of Science for English articles and abstracts using free text words and combinations of the following terms 'IL28B', 'IFN lambda', 'genomics', 'hepatitis B virus', 'interferon' 'GWAS', 'treatment', 'SNPs', 'HLA', 'polymorphisms'.

RESULTS

Genome-wide association studies convincingly demonstrated an association between SNPs in the HLA locus and spontaneous resolution of HBV infection in subgroups of Asian patients, yet no information is available for Caucasians. The preliminary observations of an association between IFN-λ3 SNP and virological and serological responses to IFN in both HBeAg-positive and -negative patients could not be replicated by subsequent studies. Yet, majority of studies performed so far suffer several limitations in terms of sample size, selection of the patients, endpoints of therapy, treatment strategies and duration of follow-up.

CONCLUSIONS

While host genetics is associated with an increased likelihood of spontaneous clearance of HBV among genotype B/C patients, the relationship between IFN-λ3 polymorphisms and response to IFN has not been confirmed. Further studies in large cohorts of homogeneous patients are required, before this genetic test can be recommended in clinical practice.

Role of IL28-B polymorphisms in the treatment of chronic hepatitis B HBeAg-negative patients with peginterferon

Interleukin (IL)28-B polymorphism has been related to interferon response in the treatment of hepatitis C, but its role in chronic hepatitis B (CHB) therapy is still poorly understood. We aimed to investigate the effect of IL28-B polymorphisms in the treatment with pegylated-interferon (PEG-IFN) of patients with CHB. We retrospectively analyzed 190 patients with chronic hepatitis B e antigen (HBeAg) negative, genotype A (22%), B (12%), C (10%), D (33%), E (20%), treated with PEG-IFN alfa-2a for 48weeks; genotype analysis was performed for IL28-B polymorphisms rs12979860, rs8099917 and rs12980275 according to virological, serological and biochemical response. During 2years of follow-up 12 patients (6.3%) cleared hepatitis B surface antigen (HBsAg) with seroconversion, 40 (21%) obtained a negative viral load and 104 (54.7%) gained a biochemical response. We found a difference of distribution of rs12979860 CC genotype among different ethnicity (p=0.013). Rs12979860 CC genotype was significantly associated with serological and virological response (p<0.001); rs8099917 TT and rs12980275 AA genotypes were mostly related with virological response (p<0.001). In multivariate logistic analysis rs12979860 CC was predictive of virological response (OR=4.290; CI=1.589-11.580, p=0.004) and serological response (OR=10.129; CI=2.440-42.044; p<0.001). Rs8099917 TT was predictive only of virological response (OR=3.746, CI=1.235-11.355; p=0.020). The E genotype was a negative predictive factor of virological response (OR=0.057; CI=0.014-0.238; p<0.001). IL28-B polymorphisms are related to different response in the treatment of CHB HBeAg-negative with PEG-IFN, and the E genotype is a novel negative predictive factor.

Association of polymorphisms in interleukin-18 and interleukin-28B genes with outcomes of hepatitis B virus infections: a meta-analysis

Several polymorphisms in the interleukin-18 (IL-18) and nterleukin-28B (IL-28B) genes have been reported to influence hepatitis B virus (HBV) infection. However, the published findings have been conflicting. We conducted meta-analyses of randomized, controlled trials to address the association of IL-18 or IL-28B polymorphisms and the outcomes of HBV infection. Weipu, Wanfang, CNKI, MEDLINE, PubMed, EMBASE, and Cochrane Library databases were employed to search for citations using the MeSH terms as "interleukin-18"/"interleukin-28B" AND "HBV" AND "gene" AND "polymorphism" without any restriction in language and publication year. Meta-analysis was conducted by RevMan 5.0 software. The results showed that the IL28B rs8099917 AA genotype (AA vs AC + CC: odds ratio (OR) = 0.63, 95 % confidence interval (CI) = 0.46-0.87) was associated with a decreased risk of hepatocellular carcinoma (HCC). Carriage of IL28B rs12979860 CC genotype was associated with an increased risk for developing liver cirrhosis among patients with HBV infection (CC vs CT + TT: OR = 1.39, 95 % CI = 1.04-1.85). Further well-designed large studies are warranted to confirm the mechanisms by which these are involved in these outcomes of HBV infection.