Peginterferon alfa-2a plus ribavirin is more effective than peginterferon alfa-2b plus ribavirin for treating chronic hepatitis C virus infection

A Synopsis of Hepatitis C Virus Treatments and Future Perspectives

Hepatitis C virus (HCV) infection is a worldwide public health problem. Chronic infection with HCV can lead to liver cirrhosis or cancer. Although some immune-competent individuals can clear the virus, others develop chronic HCV disease due to viral mutations or an impaired immune response. IFNs type I and III and the signal transduction induced by them are essential for a proper antiviral effect. Research on the viral cycle and immune escape mechanisms has formed the basis of therapeutic strategies to achieve a sustained virological response (SVR). The first therapies were based on IFNα; then, IFNα plus ribavirin (IFN-RBV); and then, pegylated-IFNα-RBV (PEGIFNα-RIV) to improve cytokine pharmacokinetics. However, the maximum SVR was 60%, and several significant side effects were observed, decreasing patients' treatment adherence. The development of direct-acting antivirals (DAAs) significantly enhanced the SVR (>90%), and the compounds were able to inhibit HCV replication without significant side effects, even in paediatric populations. The management of coinfected HBV-HCV and HCV-HIV patients has also improved based on DAA and PEG-IFNα-RBV (HBV-HCV). CD4 cells are crucial for an effective antiviral response. The IFNλ3, IL28B, TNF-α, IL-10, TLR-3, and TLR-9 gene polymorphisms are involved in viral clearance, therapeutic responses, and hepatic pathologies. Future research should focus on searching for strategies to circumvent resistance-associated substitution (RAS) to DAAs, develop new therapeutic schemes for different medical conditions, including organ transplant, and develop vaccines for long-lasting cellular and humoral responses with cross-protection against different HCV genotypes. The goal is to minimise the probability of HCV infection, HCV chronicity and hepatic carcinoma.

Diabetic Kidney Disease in Post-Transplant Diabetes Mellitus: Causes, Treatment and Outcomes

Kidney transplant recipients are a unique subgroup of chronic kidney disease patients due to their single functioning kidney, immunosuppressive agent usage, and long-term complications related to transplantation. Post-transplant diabetes mellitus (PTDM) has a significant adverse effect on renal outcomes in particular. As transplantations enable people to live longer, cardiovascular morbidity and mortality become more prevalent, and PTDM is a key risk factor for these complications. Although PTDM results from similar risk factors to those of type 2 diabetes, the conditions differ in their pathophysiology and clinical features. Transplantation itself is a risk factor for diabetes due to chronic exposure to immunosuppressive agents. Considering current evidence, this article describes the risk factors, pathogenesis, diagnostic criteria, prevention strategies, and management of PTDM. The therapeutic options are discussed regarding their safety and potential drug-drug interactions with immunosuppressive agents.

Hepatitis C Virus, Insulin Resistance, and Diabetes: A Review

Hepatitis C virus (HCV) infection and diabetes mellitus (DM) are two chronic diseases that are a cause of significant health and economic burdens worldwide. HCV is associated with the development of insulin resistance (IR) and diabetes mellitus (DM). The mechanisms through which HCV induces IR and DM include direct viral effects, pro-inflammatory cytokines and other immune-mediated processes. Type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM) are both chronic diseases that involve impaired glucose homeostasis, albeit through different mechanisms. T1DM is an autoimmune disease that leads to the destruction of pancreatic beta cells resulting in insulin deficiency. In T2DM, a combination of peripheral insulin resistance and irregular production of insulin eventually lead to beta cell destruction and insulin insufficiency. Both type 1 and type 2 DM etiologies involve a combination of genetic and environmental factors. The data on HCV and T1DM association is limited, unlike T2DM, where a large body of evidence linking HCV to T2DM is available. Here, we intend to outline the current state of knowledge on HCV, IR, and DM. This article is protected by copyright. All rights reserved.

Safety and efficacy of grazoprevir/elbasvir in the treatment of acute hepatitis C in hemodialysis patients

Treatment of hepatitis C virus (HCV) infection with direct-acting antiviral agents (DAAs) in hemodialysis patients requires extensive consideration. At present, studies regarding DAAs for acute HCV infection in such patients are limited. The present study aims to evaluate the efficacy and safety of grazoprevir (GZR) plus elbasvir (EBR) treatment in acute hepatitis C (AHC) patients undergoing hemodialysis. Patients undergoing hemodialysis who had a nosocomial acute HCV infection were enrolled. All patients received GZR 100 mg/EBR 50 mg once daily for 12 weeks and were followed up for 12 weeks. Serum alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and HCV RNA levels were monitored during treatment and follow-up periods. Sustained virologic response at 12 weeks after treatment cessation and treatment-emergent adverse events (AEs) were assessed. A total of 68 AHC patients were enrolled. All patients were infected with HCV genotype 1b and achieved SVR12. Decreasing ALT, AST, and TBIL were observed over time in the first 4 weeks and became steady thereafter. Forty-eight (70.59%) patients reported at least one AEs. The most common AEs were fatigue, headache, and nausea. Two AHC patients discontinued treatment due to serious but drug-unrelated AEs. In conclusion, GZR/EBR has a high efficacy and safety profile in hemodialysis-dependent patients with genotype 1b AHC.

Breakthroughs in hepatitis C research: from discovery to cure

In the 1970s, an unknown virus was suspected for documented cases of transfusion-associated hepatitis, a phenomenon called non-A, non-B hepatitis. In 1989, the infectious transmissible agent was identified and named hepatitis C virus (HCV) and, soon enough, the first diagnostic HCV antibody test was developed, which led to a dramatic decrease in new infections. Today, HCV infection remains a global health burden and a major cause of liver cirrhosis, hepatocellular carcinoma and liver transplantation. However, tremendous advances have been made over the decades, and HCV became the first curable, chronic viral infection. The introduction of direct antiviral agents revolutionized antiviral treatment, leading to viral eradication in more than 98% of all patients infected with HCV. This Perspective discusses the history of HCV research, which reads like a role model for successful translational research: starting from a clinical observation, specific therapeutic agents were developed, which finally were implemented in national and global elimination programmes.

Ropeginterferon alfa-2b in patients with genotype 1 chronic hepatitis C: Pharmacokinetics, safety, and preliminary efficacy

Background and Aim

Ropeginterferon alfa‐2b (P1101) is a novel long‐acting mono‐PEGylated recombinant proline interferon (IFN) conjugated to a 40 kDa branched polyethylene glycol (PEG) chain at its N‐terminus, allowing every‐two‐week injection. It received European Medicines Agency and Taiwan marketing authorization for the treatment of polycythemia vera in 2019 and 2020, respectively. This phase 2 study aimed to evaluate the pharmacokinetics, safety, and preliminary efficacy of ropeginterferon alfa‐2b as compared with PEG‐IFN‐α2a in patients with chronic hepatitis C virus genotype 1 infection.

Methods

One hundred six treatment naive patients were enrolled in this phase 2 study and randomized to four treatment groups: subcutaneous weekly PEG‐IFN‐α2a 180 μg (group 1), weekly ropeginterferon alfa‐2b 180 μg (group 2), weekly ropeginterferon alfa‐2b 270 μg (group 3), or biweekly ropeginterferon alfa‐2b 450 μg (group 4) plus ribavirin for 48 weeks.

Results

After multiple weekly administration, serum exposure (AUC_0‐τ) in ropeginterferon alfa‐2b 180 μg was approximately 41% greater and the accumulation ratio of 2‐fold greater than PEG‐IFN‐α2a 180 μg. The incidences of flu‐like symptoms were 66.7% (18/27), 53.3% (16/30), 55.0% (11/20), and 48.3% (14/29), anxiety were 14.8% (4/27), 6.7% (2/30), 0%, and 0%, and depression were 25.9% (7/27), 13.3% (4/30), 0%, and 3.4% (1/29), for groups 1–4, respectively. Two grade 2 of 3 depression were noted in PEG‐IFN‐α2a arm, but none in ropeginterferon arms. The SVR24 rates were 77.8% (21/27), 66.7% (20/30), 80% (16/20), and 69% (20/29), respectively.

Conclusions

Ropeginterferon alfa‐2b showed longer effective half‐life and superior safety profile than PEG‐IFN‐α2a. Biweekly injection of ropeginterferon alfa‐2b will be studied in larger viral hepatitis patient population.

Eliminating hepatitis C in a rural Appalachian county: protocol for the Kentucky Viral Hepatitis Treatment Study (KeY Treat), a phase IV, single-arm, open-label trial of sofosbuvir/velpatasvir for the treatment of hepatitis C

OBJECTIVES

The overall goal of the Kentucky Viral Hepatitis Treatment Study (KeY Treat) is to eliminate hepatitis C transmission from a county in Appalachian Kentucky by removing the barriers to accessing hepatitis C virus (HCV) treatment.

METHODS/ANALYSIS

KeY Treat is a phase IV, open-label, single-arm clinical trial of sofosbuvir/velpatasvir (SOF/VEL) for the treatment of viraemic HCV infections. Those eligible for KeY Treat are at least 18 years of age, viraemic and are residents of the target county. Pregnant women are not eligible. Rapid HCV RNA screening is used to determine eligibility, and those with a quantifiable viral load (VL) consenting to participate initiate SOF/VEL on the same day. All pharmacologic treatment and related medical care is provided free of charge using a non-specialist provider model. Follow-up visits occur at 2, 6 and 12 weeks during treatment to assess medication adherence (measured via VL and self-report), side effects and engagement in risk behaviours. Post-treatment visits occur at 12 weeks (sustained virologic response (SVR12) visit), 6 months and 12 months post-treatment completion to assess re-infection. A control county has also been identified, and prevalence and incidence of chronic HCV infections will be compared with the target community longitudinally. The primary outcome to assess elimination is SVR12. However, several outcomes will be measured to assess the effectiveness of removing the barriers to HCV treatment, including treatment entry, completion and re-infection. Analyses will be conducted via a generalised linear model framework that can incorporate flexible covariate adjustment and multiple outcome types with a compatible link function. Mathematical modelling will be completed assessing the impact and cost-effectiveness of the intervention.

ETHICS AND DISSEMINATION

KeY Treat has been approved by the Institutional Review Board at the University of Kentucky. Results from KeY Treat will be presented at conferences and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03949764.

PASylation Enhances the Stability, Potency, and Plasma Half-Life of Interferon α-2a: A Molecular Dynamics Simulation

In this study, the effectiveness of PASylation in enhancing the potency and plasma half-life of pharmaceutical proteins has been accredited as an alternative technique to the conventional methods such as PEGylation. Proline, alanine, and serine (PAS) chain has shown some advantages including biodegradability improvement and plasma half-life enhancement while lacking immunogenicity or toxicity. Although some experimental studies have been performed to find the mechanism behind PASylation, the detailed mechanism of PAS effects on the pharmaceutical proteins has remained obscure, especially at the molecular level. In this study, the interaction of interferon α-2a (IFN) and PAS chain is investigated using molecular dynamics simulation method. Several important parameters including secondary structure, root-mean-square distance, and solvent accessible surface area to investigate the stability, bioavailability, and bioactivity of the PASylated protein are studied. The results demonstrate that IFN conformation is not affected critically through PASylation while it results in improvement of the protein stability and bioactivity. Therefore, PASylation can be considered as a proper biological alternative technique to increase the plasma half-life of the biopharmaceutical proteins through enlarging apparent volume. The proposed simulation represents a computational approach that would provide a basis for the study of PASylated pharmaceutical proteins for different future applications.

Cost-effectiveness analysis is a mandatory strategy for health systems: evidence from a study involving therapies for hepatitis C

Cost-effectiveness analysis is essential in health decision making. Several countries use it as synthesis of evidence to incorporate health technologies. The protease inhibitors (PI) boceprevir (BOC) and telaprevir (TVR) are indicated for chronic hepatitis C treatment and were incorporated in guidelines worldwide. Pre-marketing clinical trials showed higher sustained virological response rates in relation to previous therapies, but the incorporation of PIs generated a significant financial impact. The aim of this study was to discuss the relevance of cost-effectiveness analysis through a study that involved the inclusion of PIs in a clinical protocol. The analysis was part of a real-life study that included patients infected with hepatitis C virus genotype 1 treated in a tertiary university hospital in Brazil. Triple therapies (TT) with ribavirin (RBV), peginterferon α-2a (Peg-INF α-2a) and BOC or TVR were compared to dual therapy with RBV and Peg-INF α-2a. Sensitivity analysis of the cost-effectiveness ratio indicated an 88.2% chance of TTs presenting a higher cost per cure. The incremental cost-effectiveness ratios (ICER) exceeded the Brazilian gross domestic product (GDP) per capita by three times in all proposed scenarios. The sensitivity of ICER showed an 88.4% chance of TT not being cost-effective. The impact of PI incorporation was negative and the conduct about this could have been different if a previous cost-effectiveness analysis had been conducted.

Comparison of Compliance and Efficacy of Pegylated Interferon α-2a and α-2b in Adults with Chronic Hepatitis C

This study compares treatment completion rates and outcomes in hepatitis C virus (HCV) patients between those aged <60 and ≥60 years receiving pegylated interferon (PEG-IFN) α-2a or α-2b combined with ribavirin. No significant differences were found in treatment completion rates and virological responses between age-stratified patients or between genotype-stratified patients receiving PEG-IFN α-2a versus PEG-IFN α-2b. Significantly more patients ≥60 years of receiving PEG-IFN α-2b exhibited an early virological response compared to those receiving PEG-IFN α-2a (P = 0.002); for patients <60 years of age, treatment outcomes were similar between the 2 groups. More liver fibrosis was observed in patients with HCV of genotype 1 than in those with genotypes 2 or 3. Mean changes in pre- and post-treatment fibrosis variables (bilirubin, platelet count, liver enzymes, FIB-4, and APRI) in HCV genotype 1 patients were greater in those receiving PEG-IFN α-2b than in those receiving PEG-IFN α-2a. Significant differences were not observed between age- and HCV genotype-stratified patients receiving PEG-IFN α-2a and -α-2b, but α-2b appears to have a modest efficacy advantage over α-2b, particularly in male HCV patients ≥60 years of age.

Hepatitis C virus core protein-induced miR-93-5p up-regulation inhibits interferon signaling pathway by targeting IFNAR1

AIM

To investigate the mechanism by which hepatitis C virus (HCV) core protein-induced miR-93-5p up-regulation regulates the interferon (IFN) signaling pathway.

METHODS

HCV-1b core protein was exogenously expressed in Huh7 cells using pcDNA3.1 (+) vector. The expression of miR-93-5p and interferon receptor 1 (IFNAR1) was measured using quantitative reverse transcription-polymerase chain reaction and Western blot. The protein expression and phosphorylation level of STAT1 were evaluated by Western blot. The overexpression and silencing of miR-93-5p and IFNAR1 were performed using miR-93-5p agomir and antagomir, and pcDNA3.1-IFNAR1 and IFNAR1 siRNA, respectively. Luciferase assay was used to identify whether IFNAR1 is a target of miR-93-5p. Cellular experiments were also conducted.

RESULTS

Serum miR-93-5p level was increased in patients with HCV-1b infection and decreased to normal level after HCV-1b clearance, but persistently increased in those with pegylated interferon-α resistance, compared with healthy subjects. Serum miR-93-5p expression had an AUC value of 0.8359 in distinguishing patients with pegylated interferon-α resistance from those with pegylated interferon-α sensitivity. HCV-1b core protein increased miR-93-5p expression and induced inactivation of the IFN signaling pathway in Huh7 cells. Furthermore, IFNAR1 was identified as a direct target of miR-93-5p, and IFNAR1 restore could rescue miR-93-5p-reduced STAT1 phosphorylation, suggesting that the miR-93-5p-IFNAR1 axis regulates the IFN signaling pathway.

CONCLUSION

HCV-1b core protein-induced miR-93-5p up-regulation inhibits the IFN signaling pathway by directly targeting IFNAR1, and the miR-93-5p-IFNAR1 axis regulates STAT1 phosphorylation. This axis may be a potential therapeutic target for HCV-1b infection.

Clinical Characteristics and Treatment Efficasy of Chronic HCV Infection Among Intravenous Drug Users in Tuzla Canton

Introduction:

Chronic HCV infection is chronic inflamatory liver disease caused by hepatitis C virus. Anti HCV prevalence among intravenous drug users (IVDU) is very high and it accounts 40% -90% (60%-90%) with the risk of 80% of developing the chronic infection.

Aim:

The aims of this study were: a) to compare clinical characteristics of chronic HCV infection among IVDU and non-users population and to detect their impact to treatment outcome; b) to investigate the treatment efficacy comparing sustained viral response (SVR) in these two populations in Tuzla Canton.

Patients and methods:

The study was retrospective-prospective and included 45 IVDU of both sexes from Tuzla Canton which were treated from chronic HCV infection with Pegilated interferon 2a/2b + ribavirin in the Clinic for Infectious Diseases and Clinic for Internal Disease of University Clinical Centre in Tuzla. The control group were presented by non-users who completed therapy in both Clinics. For statistical analyses it was used statistical package SPSS 20,0 (SPSS Inc, Chicago, IL, USA) with tests of descriptive statistics with measures of central tendency and dispersion. Quantitative variables were tested by t-test or by Mann-Whitney test. Qualitative variables were tested by hi-square test or by Fisher’s test. The standard analyse of level’s risk was used too. The analyse of predictive value of EVR for achieving the ETR and SVR was done by cross-tabulation. The impact of known factors for achieving the SVR was evaluated by logistic regression analyses. All tests were done with statistical level of significance of 95% (p=0,05).

Results:

Men were more dominant in the test group (93,3% / 61,7%), also younger age (p<0,001) and lower BMI (p=0,019). The test group had significant higher basal values of Le, Hb, Plt and ALT and tendency to lower stages of fibrosis (p=0,08). The difference in genotype frequencies was statistically significant (p=0,001) with clearly dominance of G3 and G4 among IVDU. Treatment was not complited by two patients in both groups (4,4% /3,3%). EVR was significantly higher in test group (p=0,001) so did the ETR (p=0,002) and SVR (p<0,001). Predictive factors for SVR were: age (negative predictive factor), male sex, absence of reduction of pegilated interferon and ribavirin, Metavir stage of fibrosis and presence of EVR.

Conclusion:

Population of IVDU were adherent to treatment protocol and with excellent treatment response they justified the hope of health care workers for success treatment of this population.

ADAR1 polymorphisms are related to severity of liver fibrosis in HIV/HCV-coinfected patients

The adenosine deaminase acting on RNA (ADAR1) gene is an interferon-stimulated gene involved in liver injury protection. Our aim was to analyze the association of polymorphisms within this gene with the severity of liver disease in European HIV/HCV-coinfected patients. We performed a cross-sectional study in 220 patients that underwent a liver biopsy. Five SNPs in the ADAR1 gene (rs1127326, rs1127317, rs1127314, rs1127313, rs2229857) were genotyped by GoldenGate assay. The outcome variables were fibrosis stage and necroinflammatory activity grade by METAVIR-score, aspartate aminotransferase to platelet ratio index (APRI), FIB-4 index, and fibrosis progression rate (FPR). In multivariate analysis, fibrosis progression rate (FPR) (aAMRs = 0.97) decreased in a dose-dependent manner with the presence of rs2229857_T, rs1127313_G, rs1127314_G and rs1127317_G; while rs1127326_T allele had only significant associations with FIB-4 (aAMRs ≤ 0.63) and FPR (aAMRs ≤ 0.97). Moreover, carriers of rs2229857_T, rs1127314_G, rs1127317_G, and rs1127326_T alleles were protected against advanced fibrosis (F ≥ 3) (adjusted ORs (aORs) ≤ 0.44), APRI ≥ 1.5 (aORs ≤ 0.33), and FPR ≥ 0.075 (aORs ≤ 0.45). rs1127313_G carriers showed lower odds of having F ≥ 3 (aORs = 0.39), FIB4 ≥ 3.25 (aOR = 0.22) and FPR ≥ 0.075 (aORs = 0.44). In conclusion, ADAR1 polymorphisms protected against severe liver disease in HIV/HCV-coinfected patients. These results could be used to improve therapeutic decision-making in clinical practice.

In vitro inhibitory analysis of consensus siRNAs against NS3 gene of hepatitis C virus 1a genotype

OBJECTIVE

To explore inhibitory effects of genome-specific, chemically synthesized siRNAs (small interference RNA) against NS3 gene of hepatitis C virus (HCV) 1a genotype in stable Huh-7 (human hepatoma) cells as well as against viral replication in serum-inoculated Huh-7 cells.

METHODS

Stable Huh-7 cells persistently expressing NS3 gene were produced under antibiotic gentamycin (G418) selection. The cell clones resistant to 1000 μg antibiotic concentration (G418) were picked as stable cell clones. The NS3 gene expression in stable cell clone was confirmed by RT-PCR and Western blotting. siRNA cell cytotoxicity was determined by MTT cell proliferation assay. Stable cell lines were transfected with sequence specific siRNAs and their inhibitory effects were determined by RT-PCR, real-time PCR and Western blotting. The viral replication inhibition by siRNAs in serum inoculated Huh-7 cells was determined by real-time PCR.

RESULTS

RT-PCR and Western blot analysis confirmed NS3 gene and protein expression in stable cell lines on day 10, 20 and 30 post transfection. MTT cell proliferation assay revealed that at most concentrated dose tested (50 nmol/L), siRNA had no cytotoxic effects on Huh-7 cells and cell proliferation remained unaffected. As demonstrated by the siRNA time-dependent inhibitory analysis, siRNA NS3-is44 showed maximum inhibition of NS3 gene in stable Huh-7 cell clones at 24 (80%, P = 0.013) and 48 h (75%, P = 0.002) post transfection. The impact of siRNAs on virus replication in serum inoculated Huh-7 cells also demonstrated significant decrease in viral copy number, where siRNA NS3-is44 exhibited 70% (P < 0.05) viral RNA reduction as compared to NS3-is33, which showed a 64% (P < 0.05) decrease in viral copy number. siRNA synergism (NS3-is33 + NS3-is44) decreased viral load by 84% (P < 0.05) as compared to individual inhibition by each siRNA (i.e., 64%-70% (P < 0.05)) in serum-inoculated cells. Synthetic siRNAs mixture (NS5B-is88 + NS3-is33) targeting different region of HCV genome (NS5B and NS3) also decreased HCV viral load by 85% (P < 0.05) as compared to siRNA inhibitory effects alone (70% and 64% respectively, P < 0.05).

CONCLUSIONS

siRNAs directed against NS3 gene significantly decreased mRNA and protein expression in stable cell clones. Viral replication was also vividly decreased in serum infected Huh-7 cells. Stable Huh-7 cells expressing NS3 gene is helpful to develop anti-hepatitis C drug screening assays. siRNA therapeutic potential along with other anti-HCV agents can be considered against hepatitis C.

Treatment Response and Long-Term Outcome of Peginterferon α and Ribavirin Therapy in Korean Patients with Chronic Hepatitis C

BACKGROUND/AIMS

Peginterferon plus ribavirin remains a standard therapy for patients with chronic hepatitis C (CHC) in Korea. We investigated the efficacy and long-term outcome of peginterferon and ribavirin therapy in Korean patients with CHC, particularly in relation to the stage of liver fibrosis.

METHODS

The incidence of sustained virological response (SVR), hepatic decompensation, hepatocellular carcinoma, and liver-related death was analyzed in 304 patients with CHC; the patients were followed up for a median of 54 months.

RESULTS

Among patients with HCV genotype 1, the SVR rate was 36.7% (18/49) and 67% (69/103) for patients with and without cirrhosis, respectively (p<0.001). For patients with non-1 HCV genotypes, the SVR rates were 86.0% (37/43) in cirrhotic patients and 86.2% (94/109) in noncirrhotic patients. SVR significantly reduced the risk of liverrelated death, hepatic decompensation, and hepatocellular carcinoma, which had hazard ratios of 0.27, 0.16, and 0.22, respectively (all p<0.05). However, despite the SVR rate, patients with advanced fibrosis were still at risk of developing liver-related complications.

CONCLUSIONS

A relatively high SVR rate was achieved by peginterferon plus ribavirin therapy in Korean patients with CHC, which improved their long-term outcomes. However, all CHC patients with advanced hepatic fibrosis should receive close follow-up observations, even after successful antiviral treatment.

Effects of microvirin monomers and oligomers on hepatitis C virus

Microvirin (MVN) is a carbohydrate-binding protein which shows high specificity for high-mannose type N-glycan structures. In the present study, we tried to identify whether MVN could bind to high-mannose containing hepatitis C virus (HCV) envelope glycoproteins, which are heavily decorated high-mannose glycans. In addition, recombinantly expressed MVN oligomers in di-, tri- and tetrameric form were evaluated for their viral inhibition. MVN oligomers bound more efficiently to HCV virions, and displayed in comparison with the MVN monomer a higher neutralization potency against HCV infection. The antiviral effect was furthermore affected by the peptide linker sequence connecting the MVN monomers. The results indicate that MVN oligomers such as trimers and tetramers may be used as future neutralization agents against HCV infections.

Mx1, OAS1 and OAS2 polymorphisms are associated with the severity of liver disease in HIV/HCV-coinfected patients: A cross-sectional study

The mechanisms involved in the chronic hepatitis C progression are incompletely understood. The aim was to analyze the association between 2'5'oligoadenylate synthetase 1,2 and 3 (OAS1-3) and myxovirus resistance proteins 1 (Mx1) polymorphisms and severity of liver disease in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) coinfected patients. We performed a cross-sectional study in 219 patients that underwent a liver biopsy. DNA genotyping for Mx1 (rs469390), OAS1 (rs2285934), OAS2 (rs1293762) and OAS3 (rs2010604) was performed by using GoldenGate assay. The outcome variables ion liver biopsy were: (i) significant fibrosis (F ≥ 2); (ii) moderate activity grade (A ≥ 2). Additive model of inheritance for genetic association test was used. The likelihood of having significant fibrosis (F ≥ 2) was lower in patients carrying OAS2 rs1293762 A allele [adjusted odds ratio (aOR) = 0.51; p = 0.040]. Besides, the likelihood of having moderate activity grade (A ≥ 2) was higher in patients carrying Mx1 rs464397 C allele (aOR = 1.63; p = 0.028) and Mx1 rs469390 G allele (aOR = 1.97; p = 0.005), while it was lower in patients carrying OAS1 rs2285934 A allele (aOR = 0.64; p = 0.039) and OAS2 rs1293762 A allele (aOR = 0.41; p = 0.009). In conclusion, Mx1 and OAS1-2 polymorphisms were associated with the severity of liver disease in HIV/HCV-coinfected patients, suggesting a significant role in the progression of hepatic fibrosis.

Randomized trial of combined triple therapy comprising two types of peginterferon with simeprevir in patients with hepatitis C virus genotype 1b

Simeprevir (SMV) is a potent, macrocyclic hepatitis C virus (HCV) non-structural 3/4 A protease inhibitor. This prospective study compared the efficacy and safety of SMV in combination with peginterferon α2a + ribavirin (P2aR) and with peginterferon α2b + ribavirin (P2bR) in Japanese patients with HCV genotype 1b infection.

METHODS

Hepatitis C virus genotype 1b patients were randomly assigned to receive SMV (100 mg QD) with P2aR for 12 weeks, then P2aR alone for 12 or 36 weeks; or SMV (100 mg QD) with P2bR for 12 weeks, then P2bR alone for 12 or 36 weeks. The primary endpoint was a sustained virologic response 24 weeks after completing treatment (SVR24).

RESULTS

In total, 151 patients were randomly assigned to the P2aR (n = 76) or P2bR group (n = 75). Six patients dropped out. Sustained virologic response 24 weeks after completing treatment was achieved in 55 (75.3%) of 73 P2aR patients and 55 (76.4%) of 72 P2bR patients. There was no difference in the rate of SVR24 between the two groups (P = 0.88). No differences in the proportion of patients who became HCV RNA-negative were detected between the P2aR and P2bR groups. The two groups had comparable numbers of adverse events, which led to the discontinuation of treatment in 9.6% and 8.3% of participants in the P2aR and P2bR groups, respectively.

CONCLUSION

Peginterferon α2a or α2b in combination with SMV + ribavirin therapy showed identical antiviral effects in patients with chronic hepatitis C. Also, the incidence of adverse events was identical for both regimens.

Viability of pegIFNα-RBV for CHC in the direct acting antiviral era: a practical algorithm between efficacy and cost containment

The classical pegylated interferon α (peg-IFNα) and ribavirin (RBV) treatment of chronic hepatitis C (CHC) is progressively being replaced by new direct acting antivirals, whose costs remain a major barrier to widespread use. Using baseline data and viral kinetics, we developed a predictive algorithm to allocate to DAA patients who are not going to respond to peg-IFNα/RBV. This prospective study evaluated 205 CHC patients treated with peg-IFNα/RBV. HCVRNA kinetics during the initial 3 days of therapy and baseline variables including age, genotype, fibrosis and ALTs were used to construct a prediction rule in terms of sustained virological response (SVR). One hundred and twenty-one patients achieved an SVR (59%). Variables independently associated with SVR were HCVRNA, ALT, glycaemia, viral genotype, and fibrosis. The decline of viremia from baseline to 48/72 h was significantly different in SVR compared to non-SVR patients (2.2 vs. 0.65 log10 IU/mL; p < 0.001), and was influenced by viral genotype, levels of ALT, stage of fibrosis and IL28B polymorphism. In genotype 1, HCVRNA decline <0.8 logs had a negative predictive value of 90%, and in genotype 2, HCVRNA decline >1.2 logs had a positive predictive value of 92%. A combination of HCVRNA kinetics and a score based on pre-treatment parameters was highly accurate in predicting SVR in most patients. Outcome of peg-IFNα/RBV treatment may be predicted combining evaluation of baseline variables and HCVRNA kinetics. This allows to individualize treatment, reserving newer and more expensive DAAs to CHC patients who are in most need of them.

Mouse Systems to Model Hepatitis C Virus Treatment and Associated Resistance

While addition of the first-approved protease inhibitors (PIs), telaprevir and boceprevir, to pegylated interferon (PEG-IFN) and ribavirin (RBV) combination therapy significantly increased sustained virologic response (SVR) rates, PI-based triple therapy for the treatment of chronic hepatitis C virus (HCV) infection was prone to the emergence of resistant viral variants. Meanwhile, multiple direct acting antiviral agents (DAAs) targeting either the HCV NS3/4A protease, NS5A or NS5B polymerase have been approved and these have varying potencies and distinct propensities to provoke resistance. The pre-clinical in vivo assessment of drug efficacy and resistant variant emergence underwent a great evolution over the last decade. This field had long been hampered by the lack of suitable small animal models that robustly support the entire HCV life cycle. In particular, chimeric mice with humanized livers (humanized mice) and chimpanzees have been instrumental for studying HCV inhibitors and the evolution of drug resistance. In this review, we present the different in vivo HCV infection models and discuss their applicability to assess HCV therapy response and emergence of resistant variants.

Current views on interferon therapy for HIV

INTRODUCTION

Knowledge of IFN-antiviral activity against HIV infection dates from the first years of the AIDS epidemic. Recombinant IFN had an inhibitory effect on HIV and was not toxic to peripheral blood mononuclear cells (PBMC), and this finding was the basis for the design of clinical trials that evaluated the potential role of IFN-alpha as an inhibitor of HIV replication.

AREAS COVERED

This review summarizes the history of IFN-alpha in the treatment of HIV infection with reviews of studies performed in different clinical settings; in the pre-highly active antiretroviral therapy (HAART) era, as part of a structured treatment interruption (STI) strategy, in acute HIV infection, as part of salvage therapy, and eliminating the HIV reservoir.

EXPERT OPINION

The role of IFN-alpha has been dismissed in the area of HIV therapy. For this reason, with the advent of HAART, which substantially reduced mortality and the appearance of AIDS, IFN-alpha ceased to be used as an antiretroviral agent in different strategies. In contrast, because of the promising results achieved with IFN-alpha therapy in eliminating the HIV viral reservoir, this may constitute the main research field for IFN-alpha in the HIV setting.

Meta-Analysis of Combination Therapy of Chinese Herbs Plus Interferon and Ribavirin in Patients with Chronic Hepatitis C

BACKGROUND We aimed to evaluate the combination therapy of Chinese herbs plus interferon and ribavirin in treatment of patients with chronic hepatitis C (CHC). MATERIAL AND METHODS Related databases were searched to identify randomized controlled trials (RCTs) that evaluated biochemical response, virological response, histological response, and/or adverse reactions to combination therapy of interferon and ribavirin with and without Chinese herbs. The RR (relative risk) with a 95% confidence interval (CI) was calculated. Sensitivity analysis was conducted by omitting one study at a time. Publication bias among the eligible studies was evaluated by Egger's test. RESULTS A total of 17 RCTs matched the selection criteria. Overall, combination therapies of Chinese herbs plus interferon and ribavirin achieved significantly higher ALT (alanine transaminase) and ETVR (the end-of-treatment viral response), and significantly lower levels of HA (hyaluronic acid), LN (laminin), PC III (procollagen iii peptide), IV-C (type IV collagen), decreased LC (decreasing leukocyte count), ATF (abnormal thyroid function), psychosis, and anemia in CHC patients compared with those treated without Chinese herbs. Sensitivity analysis showed no changes and no potential publication bias was found. CONCLUSIONS The current evidence suggests that combination therapy of Chinese herb plus interferon and ribavirin yields better outcome and fewer adverse events in CHC patients than that of interferon plus ribavirin therapy.

Predictors of Virological Response in 3,235 Chronic HCV Egyptian Patients Treated with Peginterferon Alpha-2a Compared with Peginterferon Alpha-2b Using Statistical Methods and Data Mining Techniques

Despite the appearance of new oral antiviral drugs, pegylated interferon (PEG-IFN)/RBV may remain the standard of care therapy for some time, and several viral and host factors are reported to be correlated with therapeutic effects. This study aimed to reveal the independent variables associated with failure of sustained virological response (SVR) to PEG-IFN alpha-2a versus PEG-IFN alpha-2b in treatment of naive chronic hepatitis C virus (HCV) Egyptian patients using both statistical methods and data mining techniques. This retrospective cohort study included 3,235 chronic hepatitis C patients enrolled in a large Egyptian medical center: 1,728 patients had been treated with PEG-IFN alpha-2a plus ribavirin (RBV) and 1,507 patients with PEG-IFN alpha-2b plus RBV between 2007 and 2011. Both multivariate analysis and Reduced Error Pruning Tree (REPTree)-based model were used to reveal the independent variables associated with treatment response. In both treatment types, alpha-fetoprotein (AFP) >10 ng/mL and HCV viremia >600 × 10(3) IU/mL were the independent baseline variables associated with failure of SVR, while male gender, decreased hemoglobin, and thyroid-stimulating hormone were the independent variables associated with good response (P < 0.05). Using REPTree-based model showed that low AFP was the factor of initial split (best predictor) of response for either PEG-IFN alpha-2a or PEG-IFN alpha-2b (cutoff value 8.53, 4.89 ng/mL, AUROC = 0.68 and 0.61, P = 0.05). Serum AFP >10 ng/mL and viral load >600 × 10(3) IU/mL are variables associated with failure of response in both treatment types. REPTree-based model could be used to assess predictors of response.

A meta-analysis platform methodology for determining the comparative effectiveness of antihepatitis C virus regimens

AIM

Many hepatitis C virus regimens are unlikely to be compared head to head. In more difficult to treat populations where there is no standard of care, trials are single arm. We describe a flexible meta-analysis platform in this setting.

METHODS

Our meta-analysis is literature based. We illustrate our methodology and show how inference can be extended to single-arm trials.

RESULTS

As an example, in the single arm setting, a regimen with response rates of 84, 72 and 54% in genotype 1a across treatment naive, previous partial responders and previous null responders, respectively, would have 95% probability of superiority to IFN-α + RBV + TPV.

CONCLUSION

This is a rigorous approach to comparative effectiveness that accounts for varying patient populations and plans for the incorporation of emerging treatments.

Evaluation of Dual Therapy in Real Life Setting in Treatment-Naïve Turkish Patients with HCV Infection: A Multicenter, Retrospective Study

BACKGROUND

Before the introduction of direct-acting antivirals in the treatment of chronic hepatitis C patients, the combination of peginterferon alpha and ribavirin was the standard therapy. Observational studies that investigated sustained virological response (SVR) rates by these drugs yielded different outcomes.

AIMS

The goal of the study was to demonstrate real life data concerning SVR rate achieved by peginterferon alpha plus ribavirin in patients who were treatment-naïve.

STUDY DESIGN

A multicenter, retrospective observational study.

METHODS

The study was conducted retrospectively on 1214 treatment naïve-patients, being treated with peginterferon alpha-2a or 2b plus ribavirin in respect of the current guidelines between 2005 and 2013. The patients' data were collected from 22 centers via a standard form, which has been prepared for this study. The data included demographic and clinical characteristics (gender, age, body weight, initial Hepatitis C virus RNA (HCV RNA) level, disease staging) as well as course of treatment (duration of treatment, outcomes, discontinuations and adverse events). Renal insufficiency, decompensated liver disease, history of transplantation, immunosuppressive therapy or autoimmune liver disease were exclusion criteria for the study. Treatment efficacy was assessed according to the patient's demographic characteristics, baseline viral load, genotype, and fibrosis scores.

RESULTS

The mean age of the patients was 50.74 (±0.64) years. Most of them were infected with genotype 1 (91.8%). SVR was achieved in 761 (62.7%) patients. SVR rate was 59.1% in genotype 1, 89.4% in genotype 2, 93.8% in genotype 3, and 33.3% in genotype 4 patients. Patients with lower viral load yielded higher SVR (65.8% vs. 58.4%, p=0.09). SVR rates according to histologic severity were found to be 69.3%, 66.3%, 59.9%, 47.3%, and 45.5% in patients with fibrosis stage 0, 1, 2, 3 and 4, respectively. The predictors of SVR were male gender, genotype 2/3, age less than 45 years, low fibrosis stage, low baseline viral load and presence of early virological response. SVR rates to each peginterferon were found to be similar in genotype 1/4 although SVR rates were found to be higher for peginterferon alpha-2b in patients with genotype 2/3. The number of patients who failed to complete treatment due to adverse effects was 33 (2.7%). The number of patients failed to complete treatment due to adverse effects was 33 (2.7%).

CONCLUSION

Our findings showed that the rate of SVR to dual therapy was higher in treatment-naïve Turkish patients than that reported in randomized controlled trials. Also peginterferon alpha-2a and alpha-2b were found to be similar in terms of SVR in genotype 1 patients.

Re-re-treatment of hepatitis C virus: Eight patients who relapsed twice after direct-acting-antiviral drugs

AIM: To determine risk factors associated with hepatitis C virus (HCV) treatment failure after direct acting antivirals in patients with complex treatment histories.

METHODS: All HCV mono-infected patients who received treatment at our institution were queried. Analysis was restricted to patients who previously failed treatment with boceprevir (BOC) or telaprevir (TVR) and started simeprevir (SMV) and sofosbuvir (SOF) ± ribavirin (RBV) between December 2013 and June 2014. Patients with human immunodeficiency virus (HIV)/HCV co-infection or patients who received a liver transplant in the past were excluded. Viral loads were recorded while on treatment and after treatment. Data collection continued until December, 31^st 2014 when data analysis was initiated. Patients missing virologic outcomes data were not included in the analysis. Analysis of 35 patients who had virologic outcome data available resulted in eight patients who were viral load negative at the end of treatment with SMF/SOF but later relapsed. Data related to patient demographics, HCV infection, and treatment history was collected in order to identify risk factors shared among patients who failed treatment with SMF/SOF.

RESULTS: Eight patients who were treated with the first generation HCV protease inhibitors BOC or TVR in combination with pegylated-interferon (PEG) and RBV who failed this triple therapy were subsequently re-treated with an off-label all-oral regimen of SMV and SOF for 12 wk, with RBV in seven cases. Treatment was initiated before the Food and Drug Administration approved a 24-wk SMV/SOF regimen for patients with liver cirrhosis. All eight patients had an end of treatment response, but later relapsed. Eight (100%) patients were male. Mean age was 56 (range, 49-64). Eight (100%) patients had previously failed PEG/RBV dual therapy at least once in addition to prior failure with triple therapy. Total number of times treated ranged from 3-6 (mean 3.8). Eight (100%) patients were male had liver cirrhosis as determined by Fibroscan or MRI. Seven (87.5%) patients had genotype 1a HCV. Seven (87.5%) patients had over 1 million IU/mL HCV RNA at the time of re-treatment.

CONCLUSION: This study identifies factors associated with SMV/SOF treatment failure and provides evidence that twleve weeks of SMV/SOF/RBV is insufficient in cirrhotics with high-titer genotype 1a HCV.

Betulinic acid exerts anti-hepatitis C virus activity via the suppression of NF-κB- and MAPK-ERK1/2-mediated COX-2 expression

BACKGROUND AND PURPOSE

This study was designed to evaluate the effect of betulinic acid (BA), extracted from Avicennia marina, on the replication of hepatitis C virus (HCV) and to investigate the mechanism of this BA-mediated anti-HCV activity.

EXPERIMENTAL APPROACH

HCV replicon and infectious systems were used to evaluate the anti-HCV activity of BA. Exogenous COX-2 or knock-down of COX-2 expression was used to investigate the role of COX-2 in the anti-HCV activity of BA. The effects of BA on the phosphorylation of NF-κB and on kinases in the MAPK signalling pathway were determined. The anti-HCV activity of BA in combination with other HCV inhibitors was also determined to assess its use as an anti-HCV supplement.

KEY RESULTS

BA inhibited HCV replication in both Ava5 replicon cells and in a cell culture-derived infectious HCV particle system. Treatment with a combination of BA and IFN-α, the protease inhibitor telaprevir or the NS5B polymerase inhibitor sofosbuvir resulted in the synergistic suppression of HCV RNA replication. Exogenous overexpression of COX-2 gradually attenuated the inhibitory effect of BA on HCV replication, suggesting that BA reduces HCV replication by suppressing the expression of COX-2. In particular, BA down-regulated HCV-induced COX-2 expression by reducing the phosphorylation of NF-κB and ERK1/2 of the MAPK signalling pathway.

CONCLUSIONS AND IMPLICATIONS

BA inhibits HCV replication by suppressing the NF-κB- and ERK1/2-mediated COX-2 pathway and may serve as a promising compound for drug development or as a potential supplement for use in the treatment of HCV-infected patients.

Differential antiviral effects of pegylated interferon-α2a and pegylated interferon-α2b in chronic hepatitis C

BACKGROUND AND OBJECTIVES

Pegylated interferon (peg-IFN)-α2a and -α2b show different pharmacokinetic properties but are used interchangeably for hepatitis C treatment in traditional dual combinations and with newer agents. We assessed whether peg-IFN antiviral effects vary with peg-IFN subtype, affecting viral response in a differential manner.

METHODS

Chronic hepatitis C patients treated with ribavirin combined with peg-IFN-α2a (N = 109) or -α2b (N = 114) were studied. Hepatitis C virus RNA quantitation was performed by Cobas TaqMan 5 min before treatment start and subsequently after 48/72 h and 7, 14, 28 and 90 days. Antiviral effect was assessed in terms of viraemia changes over treatment. Histology grading and staging, interleukin-28B (IL28B) status and baseline viral genotype, alanine aminotransferase, gamma glutamyltransferase and glucose were analysed.

RESULTS

Viraemia decline after 48/72 h and 7 days was significantly greater with peg-IFN-α2b (1.96 and 2.12 vs 1.49 and 1.20 log10 IU/mL with peg-IFN-α2a; p < 0.001). Differences were of larger extent in patients with advanced fibrosis (p = 0.002), genotype 1 infection (p = 0.002) and CT/TT genotypes of IL28B (p = 0.001). A rebound in viral load was observed significantly more often after the first dose in patients treated with peg-IFN-α2b (78 vs 28 % in those with peg-IFN-α2a; p = 0.0001). Differences between peg-IFNs disappeared by day 28 of treatment.

CONCLUSION

There are significant pharmacodynamic differences between peg-IFN-α2a and -α2b in the early phase of chronic hepatitis C treatment. The greater early viral decline observed with peg-IFN-α2b was essentially confined to 'difficult to treat' patients. Whether this could affect response-guided treatment decision making, as well as triple drug regimens, needs to be assessed.

Grazoprevir and elbasvir: a second-generation protease inhibitor and a second-generation NS5A inhibitor in a combination regimen for treatment of chronic hepatitis C

ABSTRACT 

The emergence of direct acting antivirals against HCV infection has provided the opportunity for interferon free, all oral treatments for HCV infection in patients with HCV genotype 1 (GT1). This review describes the current data on the combination of grazoprevir and elbasvir, a second-generation NS3/4A inhibitor and a second-generation NS5A inhibitor, respectively. The regimen has shown promising results in Phase II trials in patients with GT1 with response rates >90%, even in patient groups that have been challenging to treat, such as patients with cirrhosis, HIV co-infection and previous null responders to treatment with pegylated IFN-α + ribavirin. Grazoprevir + elbasvir treatment is well tolerated. Phase III trials and trials including infections with GT2–4 + 6 are ongoing.

A comparative study of variants of pegylated interferon alpha in treatment of chronic HCV patients

HCV infection presents a vast burden in the regions of high prevalence such as Egypt, where most HCV isolates are genotype 4b. Combined treatment of three variants of pegylated interferon and ribavirin is still the standard of care in Egypt. However, no conclusive data confirming their efficacy are available. Here, 60 chronic HCV patients were randomized for ribavirin plus Peg Intron (PEG-IFNα-2b), Pegasys (PEG-IFNα-2a) or Reiveron Retard (PEG-IFNα-2a). Serum interferon and antibody (Ab) levels were measured, and responses and costs were compared. Serum interferon levels were higher in Pegasys group (1625.1 ng/mL) followed by Reiveron Retard (1076.5 ng/mL), and Peg Intron group (857.72 ng/mL). Moreover, Ab levels were the lowest in Reiveron Retard group (318.4 ng/mL), followed by Peg Intron (439.93 ng/mL), and Pegasys cases (610.83 ng/mL). The best 24-week response rates were detected in the Pegasys group (73.3%), followed by Peg Intron (66.67%), and Reiveron Retard (40%). Treatment with both Pegasys and Peg Intron were most cost-effective. Furthermore, Pegasys was superior in both 6-month response and serum interferon, despite having higher Ab levels (more antigenicity). Our data have notable clinical implications and suggest that Pegasys may be a superior choice of interferon therapy for chronic HCV under low socioeconomic conditions.

A window of opportunity: maximizing the effectiveness of new HCV regimens in the United States with the expansion of the Affordable Care Act

Patients with chronic HCV have predictable overlapping comorbidities that reduce access to care. The Affordable Care Act (ACA) presents an opportunity to focus on the benefits of the medical home model for integrated chronic disease management. New, highly effective HCV treatment regimens in combination with the medical home model could reduce disease prevalence. We sought to address challenges posed by comorbidities in patients with chronic HCV infection and limitations within our health care system, and recommend solutions to maximize the public benefit from ACA and the new drug regimen.

A cost-effectiveness model to personalize antiviral therapy in naive patients with genotype 1 chronic hepatitis C

BACKGROUND AND AIMS

Rapid virologic response is the best predictor of sustained virologic response with dual therapy in genotype-1 chronic hepatitis C, and its evaluation was proposed to tailor triple therapy in F0-F2 patients. Bio-mathematical modelling of viral dynamics during dual therapy has potentially higher accuracy than rapid virologic in the identification of patients who will eventually achieve sustained response. Study's objective was the cost-effectiveness analysis of a personalized therapy in naïve F0-F2 patients with chronic hepatitis C based on a bio-mathematical model (model-guided strategy) rather than on rapid virologic response (guideline-guided strategy).

METHODS

A deterministic bio-mathematical model of the infected cell dynamics was validated in a cohort of 135 patients treated with dual therapy. A decision-analytic economic model was then developed to compare model-guided and guideline-guided strategies in the Italian setting.

RESULTS

The outcomes of the cost-effectiveness analysis with model-guided and guideline-guided strategy were 19.1-19.4 and 18.9-19.3 quality-adjusted-life-years. Total per-patient lifetime costs were €25,200-€26,000 with model-guided strategy and €28,800-€29,900 with guideline-guided strategy. When comparing model-guided with guideline-guided strategy the former resulted more effective and less costly.

CONCLUSIONS

The adoption of the bio-mathematical predictive criterion has the potential to improve the cost-effectiveness of a personalized therapy for chronic hepatitis C, reserving triple therapy for those patients who really need it.

Protein kinase expression as a predictive factor for interferon response in chronic hepatitis C patients

Egypt has the highest prevalence of hepatitis C virus (HCV) worldwide. Currently, combined pegylated interferon and ribavirin therapy are the standard treatment. The biological activity of interferon (IFN) is mediated by the induction of intracellular antiviral proteins, such as 2'-5' oligoadenylate synthetase, and dsRNA-activated protein kinase. IFN-inducible double-stranded RNA-activated protein kinase (PKR) is thought to play a key antiviral role against HCV. Some studies observed that PKR expression was higher in sustained viral responders compared with the non-responders. The PKR is considered as antiviral toward HCV and responsible for IFN's effect against HCV while others have showed that, there were kinetic results indicate that HCV infection is not altered by reduced levels of PKR, indicating that HCV is resistant to the translational inhibitory effects of the phosphorylated forms of PKR. This study was conducted on 50 consecutive patients with chronic HCV infection (CHC) and 20 healthy controls. All the patients were subjected to clinical and laboratory assessment, abdominal ultrasound, and liver biopsy. Determination of PKR gene quantity by using a real time PCR was done at the baseline and at the end of treatment for all patients and controls. Pre-treatment levels of protein kinase gene were significantly higher in responders in comparison with non-responders (P < 0.001). It was found that 97.06% of patients who were responding to treatment had the expression of protein kinase gene greater than 2(6) cycle threshold.

Cost comparison of treating chronic hepatitis C genotype one with pegylated interferons in Ukraine

Based on the pivotal trial showing no clinically relevant differences between pegylated interferon α-2b (Peg-α-2b) and α-2a (Peg-α-2a) combined with ribavirin for treatment of chronic hepatitis C virus (HCV) genotype 1 infection in Ukraine, a cost-minimization analysis was performed using a 1 year time horizon and both a health care and patients’ perspective. A decision tree reflects treatment pathways. Drug costs were based on drug labeling and adjusted to the average body mass in Ukraine. Subgroup analysis was applied to deal with heterogeneity of patient’s weight causing dose changes. A break-even price of Peg-α-2a and Peg-α-2b (based on the average dose) was calculated. Univariate sensitivity analyses and probabilistic sensitivity analysis were carried out to reflect decision uncertainty. For an average body weight, total medical costs per patient differ from US$9220 for Peg-α-2b to US$9513 for Peg-α-2a from a health care perspective, and from US$15,212 to US$15,696 from a patients’ perspective. Sensitivity analyses show these results are robust. With average body weight, the break-even price of Peg-α-2b may be 7.3% higher than Peg-α-2a to have similar total costs.

Erythropoietin rs1617640 G allele associates with an attenuated rise of serum erythropoietin and a marked decline of hemoglobin in hepatitis C patients undergoing antiviral therapy

BACKGROUND

A decline in hemoglobin (Hb) concentration during antiviral therapy in chronic hepatitis C (CHC) is a serious side effect. It may compel to dose reduction or even termination of antiviral treatment. The activation of erythropoietin (EPO) synthesis as a physiological response to anemia and its relation to a genetic variation within the EPO gene has not been evaluated yet.

METHODS

Data of 348 CHC patients were reviewed retrospectively. Samples were genotyped for EPO rs1617640 and inosine triphosphatase (ITPA) rs1127354. Serum EPO concentrations were determined before and during therapy. Primary endpoints were set as Hb decline >3 g/dl at weeks 4 and 12.

RESULTS

EPO rs1617640 G homozygotes showed a significantly lower rise of serum EPO level over time than T allele carriers (p < 0.001). The cumulative frequency of a significant Hb reduction added up to 40%. Multivariate analysis revealed that besides age, ribavirin starting dose and baseline Hb also EPO rs1617640 G homozygosity associates with Hb reduction at week 4 (p = 0.025) and 12 (p = 0.029), while ITPA C homozygotes are at risk for Hb decline particularly early during treatment. Furthermore, EPO rs1617640 G homozygotes were more frequently in need for blood transfusion, epoetin-α supplementation, or ribavirin dose reduction (p < 0.001).

CONCLUSIONS

Our data suggest that EPO rs1617640 genotype, the rise of serum EPO concentration as well as ITPA rs1127354 genotype are promising parameters to evaluate the Hb decline during antiviral therapy. A rational adjustment of therapy with epoetin-α supplementation might prevent serious adverse events or the need to terminate treatment.

Sustained virological response to peginterferon therapy in patients infected with HCV (genotypes 2 and 3), with or without HIV

BACKGROUND

HIV infection leads to a faster progression of liver disease in subjects infected with HCV, as compared with HCV mono-infected patients. Previous reports suggest that sustained virological response (SVR) rates are lower in HIV/HCV coinfection than in HCV monoinfection. We aimed to compare SVR rates of these two populations.

METHODS

We retrospectively analyzed clinical, biochemical and virological data of HCV and HIV/HCV infected patients with HCV genotypes 2 and 3 who started anti-HCV treatment between March 2004 and November 2012, at a single large center. Intention-to-treat (ITT) and per-protocol (PP) analysis were performed. Univariate and multivariate logistic regression analyses were performed to assess predictors of SVR.

RESULTS

461 patients were analyzed: 307 (66.6%) males, 76 (16.5%) infected with HIV. Several differences at baseline between HCV monoinfected and HIV/HCV coinfected patients were observed. HCV monoinfected group was characterized by higher prevalence of genotype 2 (53% vs 5.3%), higher baseline HCV viral load (50% vs 35%), shorter mean duration of treatment (19 vs 41 weeks), more frequent use of peginterferon alfa-2a (84.5% vs 69.7%), lower prevalence of cirrhosis (6% vs 31.6%). Globally, SVR was achieved by 353 (76.6%) patients and 321 (83.8%) in the PP analysis. No statistically relevant differences were found in SVR rates between the two groups, either in ITT [78.2% (n = 301/385) vs 68.4% (n = 52/76), p =0.066, respectively] than in PP analysis [83.6% (n = 276/330) vs 84.9% (n = 45/53), p = 0.8].

CONCLUSIONS

Higher baseline viral loads and interruption of peginterferon and/or ribavirin were associated with a poor outcome of anti-HCV treatment while HIV infection was not related to major or minor probability to achieve SVR.

Peginterferon alfa-2a and peginterferon alfa-2b combined with ribavirin in patients with genotype 1 chronic hepatitis C: results of a prospective single-centre study

PURPOSE

This prospective, randomized, single-centre study compared peginterferons alfa-2a and alfa-2b, combined with ribavirin, in treating patients infected with hepatitis C virus (HCV) genotype 1.

MATERIAL/METHODS

Hundred-and-one patients received 48 weeks of open-label treatment with peginterferon alfa-2a (180 μg/week) and 111 patients received peginterferon alfa-2b (1.5 μg/kg/week). All patients received the same dose of ribavirin 1000/1200 mg/day, depending on weight. The primary efficacy endpoint was sustained virologic response (SVR), defined as undetectable HCV RNA (<50 IU/mL) 24 weeks after the end of treatment.

RESULTS

Early virologic response (EVR), defined as at least 2 log₁₀ IU/mL reduction of viral load at 12 weeks, was more common in patients treated with peginterferon alfa-2a (88% vs. 74.8%; p=0.04). However, the difference in SVR was not statistically significant (49.5% vs. 44.1%; p=0.43).

CONCLUSIONS

Peginterferon alfa-2a treated patients were also more likely to be HCV RNA negative at the end of treatment (67.3% vs. 57.7%), but this difference did not reach statistical significance. Multivariate logistic regression analysis found that SVR was associated with low fibrosis stage (F1-2 by Scheuer; p=0.001) and low serum HCV RNA level (<400,000 IU/L; p=0.023). While both forms of peginterferon showed similar efficacy as measured by SVR, use of peginterferon alfa-2b could lower the number of patients receiving unnecessary treatment beyond 12 weeks.

Pegylated interferon α plus ribavirin for the treatment of chronic hepatitis C: a multicentre independent study supported by the Italian Drug Agency

BACKGROUND

Data on the efficacy of Peg-interferon/ribavirin therapy for chronic hepatitis C are mostly derived from treatment of selected patients enrolled in clinical trials. This study aimed to assess the effectiveness of Peg-interferon/ribavirin therapy in "real world" chronic hepatitis C patients in Italy.

METHODS

Independent observational multicentre study including consecutive patients receiving Peg-interferon/ribavirin in the 18 months before (retrospective phase) and after (prospective phase) the start of the study.

RESULTS

4176 patients were eligible. The final study population consisted of 2051 patients in the retrospective and 2073 in the prospective phase. Sustained virological response was achieved by 1036 patients (50.5%) during the retrospective phase: 325 were genotypes 1/4 (34.1%) and 684 were genotypes 2/3 (67.2%) and by 800 patients (38.6%) during the prospective phase: 300 were genotypes 1/4 (28.4%) and 473 were genotypes 2/3 (51.5%). During multivariate analysis genotypes 2/3 were significantly associated with higher sustained virological response rates; cirrhosis and γ-glutamil-transpeptidase >2 times the normal limit were associated with poorer response.

CONCLUSIONS

The response to Peg-interferon/ribavirin therapy in "real world" clinical practice is distinctly lower than in registration trials. The difference in response rates was more pronounced among easy-to-treat than among difficult-to-treat hepatitis C virus genotypes.

Chronic ethanol diet increases regulatory T-cell activity and inhibits hepatitis C virus core-specific cellular immune responses in mice

AIM

Chronic ethanol consumption is associated with persistent hepatitis C viral (HCV) infection. This study explores the role of the host cellular immune response to HCV core protein in a murine model and how chronic ethanol consumption alters T-cell regulatory (Treg) populations.

METHODS

BALB/c mice were fed an isocaloric control or ethanol liquid diet. Dendritic cells (DC) were isolated after expansion with a hFl3tL-expression plasmid and subsequently transfected with HCV core protein. Core-containing DC (1 × 10(6) ) were s.c. injected (×3) in mice every 2 weeks. Splenocytes from immunized mice were isolated and stimulated with HCV core protein to measure generation of viral antigen-specific Treg, as well as secretion of interleukin (IL)-2, tumor necrosis factor (TNF)-α and IL-4. Cytotoxicity was measured by lactate dehydrogenase release from HCV core-expressing syngeneic SP2/19 myeloma cells.

RESULTS

Splenocytes from mice immunized with ethanol-derived and HCV core-loaded DC exhibited significantly lower in vitro cytotoxicity compared to mice immunized with HCV core-loaded DC derived from isocaloric pair-fed controls. Stimulation with HCV core protein triggered higher IL-2, TNF-α and IL-4 release in splenocytes following immunization with core-loaded DC derived from controls as compared to chronic ethanol-fed mice. Splenocytes derived from mice immunized with core-loaded DC isolated from ethanol-fed mice exhibited a significantly higher CD25(+) FOXP3(+) and CD4(+) FOXP3(+) Treg population.

CONCLUSION

These results suggest that immunization with HCV core-containing DC from ethanol-fed mice induces an increase in the CD25(+) FOXP3(+) and CD4(+) FOXP3(+) Treg population and may suppress HCV core-specific CD4(+) and CD8(+) T-cell immune responses.

Peginterferon alpha-2a versus peginterferon alpha-2b for chronic hepatitis C

BACKGROUND

A combination of weekly pegylated interferon (peginterferon) alpha and daily ribavirin still represents standard treatment of chronic hepatitis C infection in the majority of patients. However, it is not established which of the two licensed peginterferon products, peginterferon alpha-2a or peginterferon alpha-2b, is the most effective and has a better safety profile.

OBJECTIVES

To systematically evaluate the benefits and harms of peginterferon alpha-2a versus peginterferon alpha-2b in head-to-head randomised clinical trials in patients with chronic hepatitis C.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS until October 2013. We also searched conference abstracts, journals, and grey literature.

SELECTION CRITERIA

We included randomised clinical trials comparing peginterferon alpha-2a versus peginterferon alpha-2b given with or without co-intervention(s) (for example, ribavirin) for chronic hepatitis C. Quasi-randomised studies and observational studies as identified by the searches were also considered for assessment of harms. Our primary outcomes were all-cause mortality, liver-related morbidity, serious adverse events, adverse events leading to treatment discontinuation, other adverse events, and quality of life. The secondary outcome was sustained virological response in the blood serum.

DATA COLLECTION AND ANALYSIS

Two authors independently used a standardised data collection form. We meta-analysed data with both the fixed-effect and the random-effects models. For each outcome we calculated the relative risk (RR) with 95% confidence interval (CI) based on intention-to-treat analysis. We used domains of the trials to assess the risk of systematic errors (bias) and trial sequential analyses to assess the risks of random errors (play of chance). Intervention effects on the outcomes were assessed according to GRADE.

MAIN RESULTS

We included 17 randomised clinical trials which compared peginterferon alpha-2a plus ribavirin versus peginterferon alpha-2b plus ribavirin in 5847 patients. All trials had a high risk of bias. Very few trials reported data on very few patients for the patient-relevant outcomes all-cause mortality, liver-related morbidity, serious adverse events, and quality of life. Accordingly, we were unable to conduct meta-analyses on all-cause mortality, liver-related morbidity, and quality of life. Twelve trials reported on adverse events leading to discontinuation of treatment without clear evidence of a difference between the two peginterferons (197/2171 (9.1%) versus 311/3169 (9.9%); RR 0.84, 95% CI 0.57 to 1.22; I2 = 44%; low quality evidence). A trial sequential analysis showed that we could exclude a relative risk reduction of 20% or more on this outcome. Peginterferon alpha-2a significantly increased the number of patients who achieved a sustained virological response in the blood serum compared with peginterferon alpha-2b (1069/2099 (51%) versus 1327/3075 (43%); RR 1.12, 95% CI 1.06 to 1.18; I2= 0%, 12 trials; moderate quality evidence). Trial sequential analyses supported this result. Subgroup analyses based on risk of bias, viral genotype, and treatment history yielded similar results. Trial sequential analyses supported the results in patients with genotypes 1 and 4, but not in patients with genotypes 2 and 3.

AUTHORS' CONCLUSIONS

There is lack of evidence on patient-important outcomes and paucity of evidence on adverse events. Moderate quality evidence suggests that peginterferon alpha-2a is associated with a higher sustained virological response in serum than with peginterferon alpha-2b. This finding may be affected by the high risk of bias of the included studies . The clinical consequences of peginterferon alpha-2a versus peginterferon alpha-2b are unknown, and we cannot translate an effect on sustained virological response into comparable clinical effects because sustained virological response is still an unvalidated surrogate outcome for patient-important outcomes. The lack of evidence on patient-important outcomes and the paucity of evidence on adverse events means that we are unable to draw any conclusions about the effects of one peginterferon over the other.

Optimizing treatment for HCV genotype 4: PEG-IFN alfa 2a vs. PEG-IFN alfa 2b; the debate continues

Hepatitis C virus (HCV) remains one of the leading causes of morbidity and mortality worldwide. Combined therapy with pegylated interferon (PEG-IFN) and ribavirin is the current standard of care treatment for HCV genotype 4. Two types of PEG-IFN are commercially available. The limited number of trials that were conducted for HCV genotype 4 and the few head to head comparisons make it impossible to know which is the best option? In this article we review all available PEG-IFN trials performed worldwide for HCV genotype 4 since 2004. Unless another molecule is developed as a standalone for the treatment of HCV, PEG-IFN will continue to be a source of debate.

SVR12 is higher than SVR24 in treatment-naïve hepatitis C genotype 1 patients treated with peginterferon plus ribavirin

BACKGROUND

Randomized clinical trials (RCTs) of interventions for the hepatitis C virus have historically used sustained virological response (SVR) at 24 weeks after treatment (SVR24) as the key effect measure. However, recent RCTs investigating the efficacy of new direct acting agents (DAAs) have used SVR at 12 weeks after treatment (SVR12). While there is evidence to suggest SVR24 and SVR12 are similar in patients receiving new DAAs, this is unlikely to be true for patients receiving backbone peginterferon-ribavirin control treatment. Establishing the difference between SVR12 and SVR24 for patients receiving peginterferon-ribavirin treatment is therefore necessary to avoid biased interpretations of the benefits of newer DAAs.

METHODS

We searched the MEDLINE®, Embase™, and Cochrane CENTRAL for RCTs with a peginterferon-ribavirin arm that used SVR24 and/or SVR12. As no RCTs reported on both, we pooled SVR12 and SVR24 proportions using conventional meta-analysis. Proportions were pooled separately for peginterferon alpha-2a and alpha-2b. Further, a Bayesian meta-regression model was employed to estimate the difference between SVR12 and SVR24.

RESULTS

Thirty-five RCTs including a peginterferon arm were identified. Twenty-four trials included a peginterferon alpha-2a plus ribavirin arms, of which 20 reported SVR24 and five reported SVR12. Seventeen trials included a peginterferon alpha-2b plus ribavirin arm, of which 16 reported SVR24 and one reported SVR12. Using Bayesian meta-regression, the pooled SVR12 was 6% higher than SVR24 with peginterferon alpha-2a (53% versus 47%) and 5% higher with peginterferon alpha-2b (45% versus 40%) and 95% credible intervals (CrIs) were only marginally overlapping. The meta-regression also demonstrated a marginally significant relative risk of 1.13 (95% CrI 0.99-1.26) of SVR12 versus SVR24. The conventional pairwise meta-analyses were consistent with these findings.

CONCLUSION

Considering the relatively large difference observed between SVR12 and SVR24, it seems reasonable to insist that future clinical trials report both to allow for complete transparency and clarity in their interpretation.

Antiviral treatment of hepatitis C virus infection and factors affecting efficacy

Hepatitis C virus (HCV) infection is the leading cause of chronic liver-related diseases, including cirrhosis, liver failure, and hepatocellular carcinoma. Currently, no effective vaccine is available for HCV infection. Polyethylene glycol interferon-α (PegIFN-α) in combination with ribavirin (RBV) is the standard of care (SOC) for chronic hepatitis C. However, the efficacy of PegIFN-α and RBV combination therapy is less than 50% for genotype 1 HCV, which is the dominant virus in humans. In addition, IFN and RBV have several severe side effects. Therefore, strategies to improve sustained virological response (SVR) rates have been an important focus for clinical physicians. The serine protease inhibitors telaprevir and boceprevir were approved by the United States Food and Drug Administration in 2011. The addition of HCV protease inhibitors to the SOC has significantly improved the efficacy of treatments for HCV infection. Several direct-acting antiviral drugs currently in late-stage clinical trials, both with and without peg-IFN and RBV, have several advantages over the previous SOC, including higher specificity and efficacy, fewer side effects, and the ability to be administered orally, and might be optimal regimens in the future. Factors affecting the efficacy of anti-HCV treatments based on IFN-α include the HCV genotype, baseline viral load, virological response during treatment, host IL28B gene polymorphisms and hepatic steatosis. However, determining the effect of the above factors on DAA therapy is necessary. In this review, we summarize the development of anti-HCV agents and assess the main factors affecting the efficacy of antiviral treatments.

Pegylated versus standard interferon plus ribavirin in chronic hepatitis C genotype 4: A systematic review and meta-analysis

AIM

Treatment of hepatitis C genotype 4 (HCV-G4) with pegylated interferon (PEG IFN) has not been adequately studied and is considered to be challenging. The aim of this meta-analysis is to systematically review and evaluate the effectiveness of 48 weeks of combined PEG IFN plus ribavirin (RBV) compared to standard interferon (IFN) plus RBV. The outcome of interest is sustained virological response (SVR).

METHODS

We searched for eligible randomized controlled trials (RCT) through May 2012. Random effects meta-analysis was used to pool the risk ratio (RR) of achieving SVR across trials.

RESULTS

Five RCT enrolling 386 patients were included. The PEG IFN/RBV group had increased likelihood of achieving SVR (RR = 1.51, 95% confidence interval [CI] = 1.08-2.10). SVR was significantly higher in PEG IFN-α-2a compared to the -α-2b group (P = 0.02). There was no statistically significant effect of ribavirin dosage on SVR (P = 0.55). The quality of evidence was moderate overall and limited by heterogeneity.

CONCLUSION

In treatment-naive patients with HCV-G4, treatment with PEG IFN plus RBV achieves higher SVR rate than treatment with IFN plus RBV.