Efficacy of boceprevir, an NS3 protease inhibitor, in combination with peginterferon alfa-2b and ribavirin in treatment-naive patients with genotype 1 hepatitis C infection (SPRINT-1): an open-label, randomised, multicentre phase 2 trial

Therapeutic Intervention of Serine Protease Inhibitors against Hepatitis C Virus

Hepatitis C virus (HCV) is a globally prevalent and hazardous disorder that is responsible for inducing several persistent and potentially fatal liver diseases. Current treatment strategies offer limited efficacy, often accompanied by severe and debilitating adverse effects. Consequently, there is an urgent and compelling need to develop novel therapeutic interventions that can provide maximum efficacy in combating HCV while minimizing the burden of adverse effects on patients. One promising target against HCV is the NS3-4A serine protease, a complex composed of two HCV-encoded proteins. This non-covalent heterodimer is crucial in the viral life cycle and has become a primary focus for therapeutic interventions. Although peginterferon, combined with ribavirin, is commonly employed for HCV treatment, its efficacy is hampered by significant adverse effects that can profoundly impact patients' quality of life. In recent years, the development of direct-acting antiviral agents (DAAs) has emerged as a breakthrough in HCV therapy. These agents exhibit remarkable potency against the virus and have demonstrated fewer adverse effects when combined with other DAAs. However, it is important to note that there is a potential for developing resistance to DAAs due to alterations in the amino acid position of the NS3-4A protease. This emphasizes the need for ongoing research to identify strategies that can minimize the emergence of resistance and ensure long-term effectiveness. While the combination of DAAs holds promise for HCV treatment, it is crucial to consider the possibility of drug-drug interactions. These interactions may occur when different DAAs are used concurrently, potentially compromising their therapeutic efficacy. Therefore, carefully evaluating and monitoring potential drug interactions are vital to optimize treatment outcomes. In the pursuit of novel therapeutic interventions for HCV, the field of computational biology and bioinformatics has emerged as a valuable tool. These advanced technologies and methodologies enable the development and design of new drugs and therapeutic agents that exhibit maximum efficacy, reduced risk of resistance, and minimal adverse effects. By leveraging computational approaches, researchers can efficiently screen and optimize potential candidates, accelerating the discovery and development of highly effective treatments for HCV, treatments.

Direct-acting antiviral resistance of Hepatitis C virus is promoted by epistasis

Direct-acting antiviral agents (DAAs) provide efficacious therapeutic treatments for chronic Hepatitis C virus (HCV) infection. However, emergence of drug resistance mutations (DRMs) can greatly affect treatment outcomes and impede virological cure. While multiple DRMs have been observed for all currently used DAAs, the evolutionary determinants of such mutations are not currently well understood. Here, by considering DAAs targeting the nonstructural 3 (NS3) protein of HCV, we present results suggesting that epistasis plays an important role in the evolution of DRMs. Employing a sequence-based fitness landscape model whose predictions correlate highly with experimental data, we identify specific DRMs that are associated with strong epistatic interactions, and these are found to be enriched in multiple NS3-specific DAAs. Evolutionary modelling further supports that the identified DRMs involve compensatory mutational interactions that facilitate relatively easy escape from drug-induced selection pressures. Our results indicate that accounting for epistasis is important for designing future HCV NS3-targeting DAAs.

Hepatitis C Virus: Insights Into Its History, Treatment, Challenges, and Future Directions

Hepatitis C virus (HCV) is a global public health concern with significant impacts. It primarily spreads through blood-to-blood contact, such as sharing needles among drug users. Given the wide prevalence of risk factors, HCV continues to pose a major threat. Hence, it is crucial to understand its characteristics, structure, and genotypes to prevent, treat, and potentially eradicate it. This narrative review aims to explore the history of HCV treatment, highlight the breakthroughs achieved with direct-acting antiviral (DAA) therapy, address potential barriers to HCV eradication, and discuss future treatment possibilities. For this article, relevant studies were identified using various databases, including PubMed, ClinicalTrials.gov, and Journal Storage. The literature search revealed that after identifying HCV and studying its characteristics, interferon alfa and ribavirin became primary treatment options. However, due to their limited coverage against different HCV genotypes, ethnic variations, and suboptimal sustained virological response, the development of DAAs became essential. Combining various DAAs, such as sofosbuvir and velpatasvir, for a duration of 12 weeks has become the standard HCV treatment, with effectiveness against most genotypes. Additionally, ongoing clinical trials have shown promising results for other drugs such as CDI31244/sofosbuvir/velpatasvir, sofosbuvir/coblopasvir, and daclatasvir/asunaprevir. Despite the success of DAAs and ongoing efforts to discover more effective treatments, the high costs of DAAs pose a significant challenge to eradicating HCV, as not all patients can afford these expensive therapies. Furthermore, the ability of HCV to mutate limits the potential for vaccine development. Therefore, it is crucial to focus on developing more cost-effective strategies to control the spread of HCV and create novel, highly effective, and affordable DAAs.

Advances in covalent drug discovery

Covalent drugs have been used to treat diseases for more than a century, but tools that facilitate the rational design of covalent drugs have emerged more recently. The purposeful addition of reactive functional groups to existing ligands can enable potent and selective inhibition of target proteins, as demonstrated by the covalent epidermal growth factor receptor (EGFR) and Bruton's tyrosine kinase (BTK) inhibitors used to treat various cancers. Moreover, the identification of covalent ligands through 'electrophile-first' approaches has also led to the discovery of covalent drugs, such as covalent inhibitors for KRAS(G12C) and SARS-CoV-2 main protease. In particular, the discovery of KRAS(G12C) inhibitors validates the use of covalent screening technologies, which have become more powerful and widespread over the past decade. Chemoproteomics platforms have emerged to complement covalent ligand screening and assist in ligand discovery, selectivity profiling and target identification. This Review showcases covalent drug discovery milestones with emphasis on the lessons learned from these programmes and how an evolving toolbox of covalent drug discovery techniques facilitates success in this field.

Extended Applications of Small-Molecule Covalent Inhibitors toward Novel Therapeutic Targets

Recently, small-molecule covalent inhibitors have been accepted as a practical tool for targeting previously "undruggable" proteins. The high target selectivity of modern covalent inhibitors is now alleviating toxicity concerns regarding the covalent modifications of proteins. However, despite the tremendous clinical success of current covalent inhibitors, there are still unmet medical needs that covalent inhibitors have not yet addressed. This review categorized representative covalent inhibitors based on their mechanism of covalent inhibition: conventional covalent inhibitors, targeted covalent inhibitors (TCIs), and expanded TCIs. By reviewing both Food and Drug Administration (FDA)-approved drugs and drug candidates from recent literature, we provide insight into the future direction of covalent inhibitor development.

Applications of covalent chemistry in targeted protein degradation

Proteolysis-targeting chimeras (PROTACs) and targeted covalent inhibitors (TCIs) are currently two exciting strategies in the fields of chemical biology and drug discovery. Extensive research in these two fields has been conducted, and significant progress in these fields has resulted in many clinical candidates, some of which have been approved by FDA. Recently, a novel concept termed covalent PROTACs that combine these two strategies has emerged and gained an increasing interest in the past several years. Herein, we briefly review and highlight the mechanism and advantages of TCIs and PROTACs, respectively, and the recent development of covalent PROTACs using irreversible and reversible covalent chemistry.

Identification of Doxorubicin as Repurposing Inhibitory Drug for MERS-CoV PLpro

Middle East respiratory syndrome coronavirus (MERS-CoV), belonging to the betacoronavirus genus can cause severe respiratory illnesses, accompanied by pneumonia, multiorgan failure, and ultimately death. CoVs have the ability to transgress species barriers and spread swiftly into new host species, with human-to-human transmission causing epidemic diseases. Despite the severe public health threat of MERS-CoV, there are currently no vaccines or drugs available for its treatment. MERS-CoV papain-like protease (PLpro) is a key enzyme that plays an important role in its replication. In the present study, we evaluated the inhibitory activities of doxorubicin (DOX) against the recombinant MERS-CoV PLpro by employing protease inhibition assays. Hydrolysis of fluorogenic peptide from the Z-RLRGG-AMC-peptide bond in the presence of DOX showed an IC₅₀ value of 1.67 μM at 30 min. Subsequently, we confirmed the interaction between DOX and MERS-CoV PLpro by thermal shift assay (TSA), and DOX increased ΔT_m by ~20 °C, clearly indicating a coherent interaction between the MERS-CoV PL protease and DOX. The binding site of DOX on MERS-CoV PLpro was assessed using docking techniques and molecular dynamic (MD) simulations. DOX bound to the thumb region of the catalytic domain of the MERS-CoV PLpro. MD simulation results showed flexible BL2 loops, as well as other potential residues, such as R231, R233, and G276 of MERS-CoV PLpro. Development of drug repurposing is a remarkable opportunity to quickly examine the efficacy of different aspects of treating various diseases. Protease inhibitors have been found to be effective against MERS-CoV to date, and numerous candidates are currently undergoing clinical trials to prove this. Our effort follows a in similar direction.

Cost-effectiveness of Direct Antiviral Agents for Hepatitis C Virus Infection and a Combined Intervention of Syringe Access and Medication-assisted Therapy for Opioid Use Disorders in an Injection Drug Use Population

BACKGROUND

There are too many plausible permutations and scale-up scenarios of combination hepatitis C virus (HCV) interventions for exhaustive testing in experimental trials. Therefore, we used a computer simulation to project the health and economic impacts of alternative combination intervention scenarios for people who inject drugs (PWID), focusing on direct antiviral agents (DAA) and medication-assisted treatment combined with syringe access programs (MAT+).

METHODS

We performed an allocative efficiency study, using a mathematical model to simulate the progression of HCV in PWID and its related consequences. We combined 2 previously validated simulations to estimate the cost-effectiveness of intervention strategies that included a range of coverage levels. Analyses were performed from a health-sector and societal perspective, with a 15-year time horizon and a discount rate of 3%.

RESULTS

From a health-sector perspective (excluding criminal justice system-related costs), 4 potential strategies fell on the cost-efficiency frontier. At 20% coverage, DAAs had an incremental cost-effectiveness ratio (ICER) of $27 251/quality-adjusted life-year (QALY). Combinations of DAA at 20% with MAT+ at 20%, 40%, and 80% coverage had ICERs of $165 985/QALY, $325 860/QALY, and $399 189/QALY, respectively. When analyzed from a societal perspective (including criminal justice system-related costs), DAA at 20% with MAT+ at 80% was the most effective intervention and was cost saving. While DAA at 20% with MAT+ at 80% was more expensive (eg, less cost saving) than MAT+ at 80% alone without DAA, it offered a favorable value compared to MAT+ at 80% alone ($23 932/QALY).

CONCLUSIONS

When considering health-sector costs alone, DAA alone was the most cost-effective intervention. However, with criminal justice system-related costs, DAA and MAT+ implemented together became the most cost-effective intervention.

Hepatitis C Virus Treatment: Simplifying the Simple and Optimizing the Difficult

The availability of safe, efficacious, oral direct-acting antivirals (DAAs) have ushered in a new era of hepatitis C treatment with potential to eliminate hepatitis C as a public health threat. To achieve population-level effectiveness of these oral DAAs, hepatitis C treatment by a wide range of providers in different settings will be essential to increase the number of persons treated. We provide a clinical review of hepatitis C treatment with a focus on practical tools for management of hepatitis C in majority of currently infected individuals who can be easily cured and optimization of treatment for those in whom treatment may not be as simple.

Impact of IFN-Free and IFN-Based Treatment on Blood Myeloid Dendritic Cell, Monocyte, Slan-DC, and Activated T Lymphocyte Dynamics during HCV Infection

Chronic hepatitis C virus infection leads to the activation of innate immunity, a key component in HCV fibrosis. In the past, the use of IFN-based treatment regimens did not permit an adequate evaluation of the impact of HCV clearance on immune cells, because of their antiviral and immunomodulatory properties. The recent development of direct-acting antiviral (DAA) therapy, which is associated with high rates of sustained virological response, enables a more accurate analysis of the immunological modifications following HCV eradication. We studied the dynamics of blood myeloid dendritic cells, monocytes, slan-DCs, and T lymphocytes during IFN-free and IFN-based regimens in hepatitis C virus infection.

Computer Network Simulation with ns-3: A Systematic Literature Review

Complexity of current computer networks, including e.g., local networks, large structured networks, wireless sensor networks, datacenter backbones, requires a thorough study to perform analysis and support design. Simulation is a tool of paramount importance to encompass all the different aspects that contribute to design quality and network performance (including as well energy issues, security management overheads, dependability), due to the fact that such complexity produces several interactions at all network layers that is not easily modellable with analytic approaches. In this systematic literature review we aim to analyze, basing our investigation on available literature, the adoption of a popular network simulator, namely ns-3, and its use in the scientific community. More in detail, we are interested in understanding what are the impacted application domains in which authors prefer ns-3 to other similar tools and how extensible it is in practice according to the experience of authors. The results of our analysis, which has been conducted by especially focusing on 128 papers published between 2009 to 2019, reveals that 10% of the evaluated papers were discarded because they represented informal literature; most of the studies presented comparisons among different network simulators, beyond ns-3 and conceptual studies related to performance assessment and validation and routing protocols. Only about 30% of considered studies present extensions of ns-3 in terms of new modules and only about 10% present effective case studies demonstrating the effectiveness of employing network simulator in real application, except conceptual and modeling studies.

Safety Profile of a Multi-Antigenic DNA Vaccine Against Hepatitis C Virus

Despite direct acting antivirals (DAAs) curing >95% of individuals infected with hepatitis C (HCV), in order to achieve the World Health Organization HCV Global Elimination Goals by 2030 there are still major challenges that need to be overcome. DAAs alone are unlikely to eliminate HCV in the absence of a vaccine that can limit viral transmission. Consequently, a prophylactic HCV vaccine is necessary to relieve the worldwide burden of HCV disease. DNA vaccines are a promising vaccine platform due to their commercial viability and ability to elicit robust T-cell-mediated immunity (CMI). We have developed a novel cytolytic DNA vaccine that encodes non-structural HCV proteins and a truncated mouse perforin (PRF), which is more immunogenic than the respective canonical DNA vaccine lacking PRF. Initially we assessed the ability of the HCV pNS3-PRF and pNS4/5-PRF DNA vaccines to elicit robust long-term CMI without any adverse side-effects in mice. Interferon-γ (IFN-γ) enzyme-linked immunosorbent spot (ELISpot) assay was used to evaluate CMI against NS3, NS4 and NS5B in a dose-dependent manner. This analysis showed a dose-dependent bell-curve of HCV-specific responses in vaccinated animals. We then thoroughly examined the effects associated with reactogenicity of cytolytic DNA vaccination with the multi-antigenic HCV DNA vaccine (pNS3/4/5B). Hematological, biochemical and histological studies were performed in male Sprague Dawley rats with a relative vaccine dose 10–20-fold higher than the proposed dose in Phase I clinical studies. The vaccine was well tolerated, and no toxicity was observed. Thus, the cytolytic multi-antigenic DNA vaccine is safe and elicits broad memory CMI.

A comparison of machine learning algorithms for the prediction of Hepatitis C NS3 protease cleavage sites

Hepatitis is a global disease that is on the rise and is currently the cause of more deaths than the human immunodeficiency virus each year. As a result, there is an increasing need for antivirals. Previously, effective antivirals have been found in the form of substrate-mimetic antiviral protease inhibitors. The application of machine learning has been used to predict cleavage patterns of viral proteases to provide information for future drug design. This study has successfully applied and compared several machine learning algorithms to hepatitis C viral NS3 serine protease cleavage data. Results have found that differences in sequence-extraction methods can outweigh differences in algorithm choice. Models produced from pseudo-coded datasets all performed with high accuracy and outperformed models created with orthogonal-coded datasets. However, no single pseudo-model performed significantly better than any other. Evaluation of performance measures also show that the correct choice of model scoring system is essential for unbiased model assessment.

Real-world health care utilization in treatment of HCV: Results from the Canadian SIMPLE observational trial

Background: As hepatitis C virus (HCV) treatment continues to evolve, there is an ongoing need to understand and optimize real-world disease management. The primary objective of the SIMPLE study was to describe the real-life management of genotype 1 (G1) HCV in Canada treated with boceprevir + pegylated interferon and ribavirin therapy. Methods: This was an observational, prospective cohort, multicentre, non-interventional study of patients with G1 HCV. A single cohort of adult patients were to be managed as per standard of care (SoC) and treated with 4 weeks of PegRBV dual therapy, followed by boceprevir + PegRBV for 24–44 weeks, with 24-weeks follow-up. Treatment compliance, health care resource utilization (HCRU), HCV viral load, and hematological adverse event (AE) data were collected. Results: This study enrolled 159 patients. All investigators were well educated on the Canadian consensus guidelines for HCV management but only a minority of patients were treated according to treatment guidelines. Viral response was achieved by >50% of patients by week 8 of therapy and in 50%–60% of tested patients during follow-up. An average of 17.9 HCRU visits were reported during the study period. The most commonly used resources were nursing visits for routine follow-up. Conclusions: Results from this real-world study suggest that most patients were not treated according to the product monograph. Further studies are required to determine how oral treatments fit into this paradigm and how these findings extrapolate to the current treatment model. This study can serve as a benchmark for future real-world treatment including heath care utilization analyses.

Interferon at the cellular, individual, and population level in hepatitis C virus infection: Its role in the interferon-free treatment era

The advent of powerful direct-acting antiviral agents (DAAs) has revolutionized the treatment of hepatitis C. DAAs cure nearly all patients with short duration, oral treatments. Significant efforts are now underway to optimize DAA-based treatments. We discuss the potential role of interferon in this optimization. Clinical studies present compelling evidence that DAAs perform better in treatment-naive individuals than in individuals who previously failed treatment with interferon, a surprising correlation because interferon and DAAs are thought to act independently. Recent mathematical models explore a mechanistic hypothesis underlying this correlation. The hypothesis invokes the action of interferon at the cellular, individual, and population levels. Strong interferon responses prevent the productive infection of cells, reduce viral replication, and impede the development of resistance to DAAs in infected individuals and improve cure rates elicited by DAAs in treated populations. The models develop descriptions of these processes, integrate them into a comprehensive framework, and capture clinical data quantitatively, providing a successful test of the hypothesis. Individuals with strong endogenous interferon responses thus present a promising subpopulation for reducing DAA treatment durations. This review discusses the conceptual advances made by the models, highlights the new insights they unravel, and examines their applicability to optimize DAA-based treatments.

Incorporating single-arm evidence into a network meta-analysis using aggregate level matching: Assessing the impact

Increasingly, single-armed evidence is included in health technology assessment submissions when companies are seeking reimbursement for new drugs. While it is recognized that randomized controlled trials provide a higher standard of evidence, these are not available for many new agents that have been granted licenses in recent years. Therefore, it is important to examine whether alternative strategies for assessing this evidence may be used. In this work, we examine approaches to incorporating single-armed evidence formally in the evaluation process. We consider matching aggregate level covariates to comparator arms or trials and including this evidence in a network meta-analysis. We consider two methods of matching: (i) we include the chosen matched arm in the data set itself as a comparator for the single-arm trial; (ii) we use the baseline odds of an event in a chosen matched trial to use as a plug-in estimator for the single-arm trial. We illustrate that the synthesis of evidence resulting from such a setup is sensitive to the between-study variability, formulation of the prior for the between-design effect, weight given to the single-arm evidence, and extent of the bias in single-armed evidence. We provide a flowchart for the process involved in such a synthesis and highlight additional sensitivity analyses that should be carried out. This work was motivated by a hepatitis C data set, where many agents have only been examined in single-arm studies. We present the results of our methods applied to this data set.

Vaccination to prevent T cell subversion can protect against persistent hepacivirus infection

Efforts to develop an effective vaccine against the hepatitis C virus (HCV; human hepacivirus) have been stymied by a lack of small animal models. Here, we describe an experimental rat model of chronic HCV-related hepacivirus infection and its response to T cell immunization. Immune-competent rats challenged with a rodent hepacivirus (RHV) develop chronic viremia characterized by expansion of non-functional CD8⁺ T cells. Single-dose vaccination with a recombinant adenovirus vector expressing hepacivirus non-structural proteins induces effective immunity in majority of rats. Resolution of infection coincides with a vigorous recall of intrahepatic cellular responses. Host selection of viral CD8 escape variants can subvert vaccine-conferred immunity. Transient depletion of CD8⁺ cells from vaccinated rats prolongs infection, while CD4⁺ cell depletion results in chronic viremia. These results provide direct evidence that co-operation between CD4⁺ and CD8⁺ T cells is important for hepacivirus immunity, and that subversion of responses can be prevented by prophylactic vaccination.

Development of a HCV vaccine is hampered by a lack of appropriate small animal models. Here, Hartlage et al. describe a rat model of hepacivirus persistence and show that persistence can be prevented by vaccination with viral non-structural proteins.

An update on the management of hepatitis C virus and human immunodeficiency virus co-infection

An estimated 2.3 million people globally are co-infected with HIV and HCV. Liver disease is now a leading cause of non-AIDS-related mortality among HIV-infected patients. The development of direct-acting antiviral agents has revolutionized the treatment of HIV/HCV co-infection with sustained virologic response response rates above 95% in most patient populations. This article provides an update on the management of acute and chronic HCV in patients co-infected with HIV including a section on drug–drug interactions.

Overview of Direct-Acting Antiviral Drugs and Drug Resistance of Hepatitis C Virus

The advent of direct-acting antivirals (DAAs) has brought about a sudden renaissance in the treatment of chronic hepatitis C virus (HCV) infection with SVR rates now routinely >90%. However, due to the error-prone nature of the HCV RNA polymerase, resistance-associated substitutions (RASs) to DAAs may be present at baseline and can result in a significant effect on treatment outcomes and hamper the achievement of sustained virologic response. By further understanding the patterns and nature of these RASs, it is anticipated that the incidence of treatment failure will continue to decrease in frequency with the development of drug regimens with increasing potency, barrier to resistance, and genotypic efficacy. This review summarizes our current knowledge of RASs associated with HCV infection as well as the clinical effect of RASs on treatment with currently available DAA regimens.

Prevalence of hepatitis C virus NS5A resistance-associated substitutions in chronic infection with genotype 1: A pooled analysis based on deposited sequences in GenBank

INTRODUCTION

Resistance-associated substitutions (RASs) in the NS5A gene of hepatitis C virus (HCV) has been studied as one of the predictors of response to NS5A inhibitor-containing regimens. This study aimed to evaluate the prevalence of pre-treatment naturally-occurring NS5A RASs in HCV isolates from patients with chronic HCV genotype 1 (HCV-1) infection retrieved from GenBank.

METHODS

In the search procedure, the studies with published HCV-1 NS5A sequence in GenBank were screened and evaluated for inclusion in the pooled analysis. The sequences of the included studies were retrieved from GenBank and evaluated for substitutions in amino acid positions24, 26, 28, 29, 30, 31, 32, 38, 58, 62, 92 and 93 of HCV NS5A including RASs and RASs conferring >100 resistance fold change (RASs >100X).

RESULTS

In the pooled analysis, 2409 isolates from patients with HCV-1 infection were included, consisting 1305 (54.2%) HCV-1a and 1104 (45.8%) HCV-1b isolates. The prevalence of NS5A RASs and RASs >100X were 16.0% (95%CI = 14.6%-17.5%) and 4.7% (95%CI = 3.9%-5.6%), respectively. The NS5A RASs were more frequently observed in HCV-1b isolates than in HCV-1a isolates (P < 0.001).

CONCLUSION

The naturally-occurring HCV NS5A RASs especially those with clinical relevance (RASs >100X) are observed in a small (4.7%) number of patients with HCV-1 infection.

Rapid and persistent decline in soluble CD163 with successful direct-acting antiviral therapy and associations with chronic hepatitis C histology

BACKGROUND AND AIM

Soluble CD 163 (sCD163) is released from activated liver macrophages in chronic viral hepatitis C (HCV) and serum levels reflect liver disease severity. The impact of direct-acting antiviral (DAA)-therapy on sCD163-levels and the ability of sCD163 to predict the presence of liver fibrosis remain unclear. In a combined observational and prospective study, we aimed to investigate changes in sCD163 with DAA-treatment, to investigate associations between sCD163 and histopathological activity and fibrosis and to validate the sCD163-based fibrosis score in HCV-patients.

METHODS

We examined three groups of patients: an Australian (n = 28) treated with pegylated-interferon and a first-generation DAA, a Danish (n = 38) treated with sofosbuvir-based DAA-regimens and a Japanese (n = 562) assessed for activity and fibrosis (Metavir scoring system) in liver biopsies. Serum sCD163-levels were quantified by ELISA.

RESULTS

Thirteen (46%) of the Australian patients achieved sustained virological response (SVR) and only these patients had significant decreases in sCD163-levels (2.7 (95%CI:1.9-3.6) vs. 4.1(2.9-5.7) mg L ^- 1, p = .008). In the Danish group, 37 (97%) patients achieved SVR at 12-weeks post-treatment with 32% reduction in sCD163-levels (5.0 (4.3-5.8) vs. 7.4 (6.3-8.7), p < .001). The decline was rapid and persisted 12 months after treatment cessation (p < .007). sCD163 levels increased in parallel with inflammatory activity and fibrosis (p < .001). The sCD163-based fibrosis score outperformed established fibrosis scores for significant fibrosis (areas under the receiver operating characteristics curves (AUROCs): 0.79 (0.75-0.83) vs. aspartate aminotransferase to platelet ratio index (APRI) 0.73 (0.69-0.77), Fibrosis-4 (FIB-4) 0.74 (0.70-0.78), p < .001).

CONCLUSION

sCD163-levels decline rapidly with successful DAA therapy and are associated with histological inflammatory activity and fibrosis, confirming a key role for macrophages in HCV inflammation and fibrosis and supporting sCD163 as a biomarker of treatment response.

Diagnosis and Management of Hepatitis C Infection in Primary Care Settings

Hepatitis C virus (HCV) infection is a significant health problem worldwide, and is the leading cause of cirrhosis, hepatocellular carcinoma, and liver transplantation in the United States. The management of HCV has changed significantly over the last 5 years, as treatments have become simpler and more efficacious. Medication efficacy is now greater than 90%, with a high barrier to resistance and few side effects. This review is a collaboration between primary care and hepatology providers to explore all aspects of HCV management: acute versus chronic HCV infection, transmission and testing, and diagnosis and treatment. Specific medications for the treatment of HCV infection are considered, and patient and medication factors including genotype, liver disease status, and comorbidities affecting medication choice are discussed. This is a new era for the management of HCV infection, and interested primary care physicians, family doctors, and general internists can be at the forefront of diagnosis, management, and treatment of HCV.

Neutralization effects of antibody elicited by chimeric HBV S antigen viral-like particles presenting HCV neutralization epitopes

Hepatitis C virus (HCV) infection is a major public health problem despite effectual direct-acting antivirals (DAAs) therapy. Development of a prophylactic vaccine is essential to block spread of HCV infection. The HBV small surface antigen (HBsAg-S) can self-assemble into virus-like particles (VLPs), has higher immunogenicity and is used as a vaccine against HBV infections. Chimeric HBsAg-S proteins with foreign epitopes allow VLP formation and induce the specific humoral and cellular immune responses against the foreign proteins. In this study, we investigated the immune responses induced by chimeric VLPs with HCV neutralizing epitopes and HBV S antigen in mice. The chimeric HCV-HBV VLPs expressing neutralizing epitopes were prepared and purified. BALB/c mice were immunized with purified chimeric VLPs and the serum neutralizing antibodies were analyzed. We found that these chimeric VLPs induced neutralizing antibodies against HCV in mice. Additionally, the murine serum neutralized infections with HCV pseudoparticles and cell-cultured viruses derived from different heterologous 1a, 1b and 2a genotypes. We also found that immunization with chimeric VLPs induced anti-HBsAg antibodies. This study provides a novel strategy for development of a HCV prophylactic neutralizing epitope vaccine and a HCV-HBV bivalent prophylactic vaccine.

Occurrence of late relapse of hepatitis C virus confirmed by molecular analysis after sustained virologic response to interferon-ribavirin-based therapy

AIM

The optimal duration of follow-up for patients who achieve sustained virologic responses (SVR) has become an important issue. Reports on long-term follow-up of SVR have indicated that 99% of patients maintained SVR. However, the limitations of a majority of studies include small patient numbers, short study periods, and lack of molecular analysis of hepatitis C virus (HCV) genome. The present study sought to evaluate the late relapse rate in long-term follow-up of patients who achieved SVR, with molecular analysis of HCV.

METHODS

A total of 224 patients with chronic hepatitis C who were treated by interferon and ribavirin-based therapy and achieved SVR were enrolled. All patients were recommended for follow-up every 6 or 12 months.

RESULTS

The mean follow-up period was 6.0 years (range, 1.0-13.6 years). Cumulative 5- and 10-year follow-up rates of the patients after SVR were 87.8% and 78.8%, respectively. Cumulative 5- and 10-year follow-up rates of serum HCV RNA after SVR were 85.5% and 52.6%, respectively. Two patients had detectable serum HCV RNA at 20 and 30 months, respectively, after SVR. Phylogenetic analyses of core, non-structural protein 3, and 5A regions of HCV strains from late relapse patients confirmed the same strain was present at baseline and late relapse.

CONCLUSIONS

Two of 224 patients developed late relapse of HCV by the original strain, which was confirmed by direct sequencing analysis. Although few patients may develop late relapse, SVR achieved with interferon and ribavirin-based therapy is durable for prolonged periods.

Spur-of-the-Moment Modification in National Treatment Policies Leads to a Surprising HCV Viral Suppression in All Treated Patients: Real-Life Egyptian Experience

The aim of this study was to retrospectively analyze the outcome of an unscheduled change in national Egyptian policies for the treatment of hepatitis C virus (HCV), which was transpired as a result of a reduction in interferon supplies, and to manage patients who already started interferon-based therapy. After completing a priming 4-weeks course of sofosbuvir/pegylated interferon/ribavirin (SOF/PEG IFN/RBV), a 12-weeks course of sofosbuvir/daclatasvir (SOF/DCV) combination was initiated. We evaluated the sustained virologic response at 12 weeks posttreatment (SVR12) for 2 groups of patients; Group 1, which included patients who had the previous regimen with IFN priming, and group 2, which included the first consecutive group of patients who received SOF/DCV for 12 weeks from the start without IFN priming. All group 1 patients (1,214 patients) achieved SVR12 (100%) and this was statistically significant when compared with the overall SVR12 in group 2 [8,869 patients with sustained virologic response [SVR] of 98.9%] (P value <0.001). No serious adverse events were reported in both groups. In this real-life treatment experience, interferon-based directly acting antiviral treatment with SOF/PEG IFN/RBV as a priming for 4 weeks, followed by SOF/DCV combination for 12 weeks, led to HCV viral suppression in all treated patients.

Direct-acting antivirals for chronic hepatitis C

BACKGROUND

Millions of people worldwide suffer from hepatitis C, which can lead to severe liver disease, liver cancer, and death. Direct-acting antivirals (DAAs), e.g. sofosbuvir, are relatively new and expensive interventions for chronic hepatitis C, and preliminary results suggest that DAAs may eradicate hepatitis C virus (HCV) from the blood (sustained virological response). Sustained virological response (SVR) is used by investigators and regulatory agencies as a surrogate outcome for morbidity and mortality, based solely on observational evidence. However, there have been no randomised trials that have validated that usage.

OBJECTIVES

To assess the benefits and harms of DAAs in people with chronic HCV.

SEARCH METHODS

We searched for all published and unpublished trials in The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, LILACS, and BIOSIS; the Chinese Biomedical Literature Database (CBM), China Network Knowledge Information (CNKI), the Chinese Science Journal Database (VIP), Google Scholar, The Turning Research into Practice (TRIP) Database, ClinicalTrials.gov, European Medicines Agency (EMA) (www.ema.europa.eu/ema/), WHO International Clinical Trials Registry Platform (www.who.int/ictrp), the Food and Drug Administration (FDA) (www.fda.gov), and pharmaceutical company sources for ongoing or unpublished trials. Searches were last run in October 2016.

SELECTION CRITERIA

Randomised clinical trials comparing DAAs versus no intervention or placebo, alone or with co-interventions, in adults with chronic HCV. We included trials irrespective of publication type, publication status, and language.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were hepatitis C-related morbidity, serious adverse events, and health-related quality of life. Our secondary outcomes were all-cause mortality, ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, hepatocellular carcinoma, non-serious adverse events (each reported separately), and SVR. We systematically assessed risks of bias, performed Trial Sequential Analysis, and followed an eight-step procedure to assess thresholds for statistical and clinical significance. We evaluated the overall quality of the evidence, using GRADE.

MAIN RESULTS

We included a total of 138 trials randomising a total of 25,232 participants. The trials were generally short-term trials and designed primarily to assess the effect of treatment on SVR. The trials evaluated 51 different DAAs. Of these, 128 trials employed matching placebo in the control group. All included trials were at high risk of bias. Eighty-four trials involved DAAs on the market or under development (13,466 participants). Fifty-seven trials administered DAAs that were discontinued or withdrawn from the market. Study populations were treatment-naive in 95 trials, had been exposed to treatment in 17 trials, and comprised both treatment-naive and treatment-experienced individuals in 24 trials. The HCV genotypes were genotype 1 (119 trials), genotype 2 (eight trials), genotype 3 (six trials), genotype 4 (nine trials), and genotype 6 (one trial). We identified two ongoing trials.We could not reliably determine the effect of DAAs on the market or under development on our primary outcome of hepatitis C-related morbidity or all-cause mortality. There were no data on hepatitis C-related morbidity and only limited data on mortality from 11 trials (DAA 15/2377 (0.63%) versus control 1/617 (0.16%); OR 3.72, 95% CI 0.53 to 26.18, very low-quality evidence). We did not perform Trial Sequential Analysis on this outcome.There is very low quality evidence that DAAs on the market or under development do not influence serious adverse events (DAA 5.2% versus control 5.6%; OR 0.93, 95% CI 0.75 to 1.15 , 15,817 participants, 43 trials). The Trial Sequential Analysis showed that there was sufficient information to rule out that DAAs reduce the relative risk of a serious adverse event by 20% when compared with placebo. The only DAA that showed a lower risk of serious adverse events when meta-analysed separately was simeprevir (OR 0.62, 95% CI 0.45 to 0.86). However, Trial Sequential Analysis showed that there was not enough information to confirm or reject a relative risk reduction of 20%, and when one trial with an extreme result was excluded, the meta-analysis result showed no evidence of a difference.DAAs on the market or under development may reduce the risk of no SVR from 54.1% in untreated people to 23.8% in people treated with DAA (RR 0.44, 95% CI 0.37 to 0.52, 6886 participants, 32 trials, low quality evidence). Trial Sequential Analysis confirmed this meta-analysis result.Only 1/84 trials on the market or under development assessed the effects of DAAs on health-related quality of life (SF-36 mental score and SF-36 physical score).There was insufficient evidence from trials on withdrawn or discontinued DAAs to determine their effect on hepatitis C-related morbidity and all-cause mortality (OR 0.64, 95% CI 0.23 to 1.79; 5 trials, very low-quality evidence). However, these DAAs seemed to increase the risk of serious adverse events (OR 1.45, 95% CI 1.22 to 1.73; 29 trials, very low-quality evidence). Trial Sequential Analysis confirmed this meta-analysis result.None of the 138 trials provided useful data to assess the effects of DAAs on the remaining secondary outcomes (ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, and hepatocellular carcinoma).

AUTHORS' CONCLUSIONS

The evidence for our main outcomes of interest come from short-term trials, and we are unable to determine the effect of long-term treatment with DAAs. The rates of hepatitis C morbidity and mortality observed in the trials are relatively low and we are uncertain as to how DAAs affect this outcome. Overall, there is very low quality evidence that DAAs on the market or under development do not influence serious adverse events. There is insufficient evidence to judge if DAAs have beneficial or harmful effects on other clinical outcomes for chronic HCV. Simeprevir may have beneficial effects on risk of serious adverse event. In all remaining analyses, we could neither confirm nor reject that DAAs had any clinical effects. DAAs may reduce the number of people with detectable virus in their blood, but we do not have sufficient evidence from randomised trials that enables us to understand how SVR affects long-term clinical outcomes. SVR is still an outcome that needs proper validation in randomised clinical trials.

Effect of Chronic Hepatitis C Virus Treatment by Combination Therapy on Cardiovascular System

BACKGROUND

The prevalence of hepatitis C virus (HCV) in Egypt is quite high, and the combined oral direct-acting antiviral agents (DAAs) may have impressive results.

OBJECTIVE

To assess the cardiovascular effects of DAAs in patients with HCV.

METHODS

A total of 170 patients with HCV were divided into 2 groups: first group (100 patients) received triple combination therapy (pegylated interferon alfa, sofosbuvir, and ribavirin, whereas the second group (70 patients) received dual combination therapy (sofosbuvir and simeprevir). Group 1 patients were followed up for 1 year more than 3 visits, whereas group 2 patients were followed up for 6 months more than 2 visits; and the end point of the study was the development of a major cardiovascular event (eg, congestive heart failure, echocardiographic evidence of left ventricular dysfunction, occurrence of significant arrhythmias, or acute coronary syndrome). The following parameters were accomplished: medical history and clinical examination, electrocardiogram, echo-Doppler study, and laboratory investigations.

RESULTS

No significant differences were found between the 2 study groups regarding demographic criteria. None of the both group patients had developed any major cardiac event. No significant changes were observed regarding ST-T wave abnormalities, arrhythmias, or QT interval. None of the both group patients developed echocardiographic regional wall motion abnormalities at baseline or at study end. Systolic function parameters showed minute nonsignificant changes over study visits. Diastolic function parameters showed nonsignificant changes between baseline and 6-month and 12-month visits.

CONCLUSIONS

The DAAs used in combination regimen with interferon or used orally in combination do not significantly affect the cardio-vascular system.

Direct-acting antivirals for chronic hepatitis C

BACKGROUND

Millions of people worldwide suffer from hepatitis C, which can lead to severe liver disease, liver cancer, and death. Direct-acting antivirals (DAAs) are relatively new and expensive interventions for chronic hepatitis C, and preliminary results suggest that DAAs may eradicate hepatitis C virus (HCV) from the blood (sustained virological response). However, it is still questionable if eradication of hepatitis C virus in the blood eliminates hepatitis C in the body, and improves survival and leads to fewer complications.

OBJECTIVES

To assess the benefits and harms of DAAs in people with chronic HCV.

SEARCH METHODS

We searched for all published and unpublished trials in The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, LILACS, and BIOSIS; the Chinese Biomedical Literature Database (CBM), China Network Knowledge Information (CNKI), the Chinese Science Journal Database (VIP), Google Scholar, The Turning Research into Practice (TRIP) Database, ClinicalTrials.gov, European Medicines Agency (EMA) (www.ema.europa.eu/ema/), WHO International Clinical Trials Registry Platform (www.who.int/ictrp), the Food and Drug Administration (FDA) (www.fda.gov), and pharmaceutical company sources for ongoing or unpublished trials. Searches were last run in October 2016.

SELECTION CRITERIA

Randomised clinical trials comparing DAAs versus no intervention or placebo, alone or with co-interventions, in adults with chronic HCV. We included trials irrespective of publication type, publication status, and language.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were hepatitis C-related morbidity, serious adverse events, and quality of life. Our secondary outcomes were all-cause mortality, ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, hepatocellular carcinoma, non-serious adverse events (each reported separately), and sustained virological response. We systematically assessed risks of bias, performed Trial Sequential Analysis, and followed an eight-step procedure to assess thresholds for statistical and clinical significance. The overall quality of the evidence was evaluated using GRADE.

MAIN RESULTS

We included a total of 138 trials randomising a total of 25,232 participants. The 138 trials assessed the effects of 51 different DAAs. Of these, 128 trials employed matching placebo in the control group. All included trials were at high risk of bias. Eighty-four trials involved DAAs on the market or under development (13,466 participants). Fifty-seven trials administered withdrawn or discontinued DAAs. Trial participants were treatment-naive (95 trials), treatment-experienced (17 trials), or both treatment-naive and treatment-experienced (24 trials). The HCV genotypes were genotype 1 (119 trials), genotype 2 (eight trials), genotype 3 (six trials), genotype 4 (nine trials), and genotype 6 (one trial). We identified two ongoing trials.Meta-analysis of the effects of all DAAs on the market or under development showed no evidence of a difference when assessing hepatitis C-related morbidity or all-cause mortality (OR 3.72, 95% CI 0.53 to 26.18, P = 0.19, I² = 0%, 2,996 participants, 11 trials, very low-quality evidence). As there were no data on hepatitis C-related morbidity and very few data on mortality (DAA 15/2377 (0.63%) versus control 1/617 (0.16%)), it was not possible to perform Trial Sequential Analysis on hepatitis C-related morbidity or all-cause mortality.Meta-analysis of all DAAs on the market or under development showed no evidence of a difference when assessing serious adverse events (OR 0.93, 95% CI 0.75 to 1.15, P = 0.52, I² = 0%, 15,817 participants, 43 trials, very low-quality evidence). The Trial Sequential Analysis showed that the cumulative Z-score crossed the trial sequential boundary for futility, showing that there was sufficient information to rule out that DAAs compared with placebo reduced the relative risk of a serious adverse event by 20%. The only DAA that showed a significant difference on risk of serious adverse events when meta-analysed separately was simeprevir (OR 0.62, 95% CI 0.45 to 0.86). However, Trial Sequential Analysis showed that there was not enough information to confirm or reject a relative risk reduction of 20%, and when one trial with an extreme result was excluded, then the meta-analysis result showed no evidence of a difference.DAAs on the market or under development seemed to reduce the risk of no sustained virological response (RR 0.44, 95% CI 0.37 to 0.52, P < 0.00001, I² = 77%, 6886 participants, 32 trials, very low-quality evidence) and Trial Sequential Analysis confirmed this meta-analysis result.Only 1/84 trials on the market or under development assessed the effects of DAAs on health-related quality of life (SF-36 mental score and SF-36 physical score).Withdrawn or discontinued DAAs had no evidence of a difference when assessing hepatitis C-related morbidity and all-cause mortality (OR 0.64, 95% CI 0.23 to 1.79, P = 0.40, I² = 0%; 5 trials, very low-quality evidence). However, withdrawn DAAs seemed to increase the risk of serious adverse events (OR 1.45, 95% CI 1.22 to 1.73, P = 0.001, I² = 0%, 29 trials, very low-quality evidence), and Trial Sequential Analysis confirmed this meta-analysis result.Most of all outcome results were short-term results; therefore, we could neither confirm nor reject any long-term effects of DAAs. None of the 138 trials provided useful data to assess the effects of DAAs on the remaining secondary outcomes (ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, and hepatocellular carcinoma).

AUTHORS' CONCLUSIONS

Overall, DAAs on the market or under development do not seem to have any effects on risk of serious adverse events. Simeprevir may have beneficial effects on risk of serious adverse event. In all remaining analyses, we could neither confirm nor reject that DAAs had any clinical effects. DAAs seemed to reduce the risk of no sustained virological response. The clinical relevance of the effects of DAAs on no sustained virological response is questionable, as it is a non-validated surrogate outcome. All trials and outcome results were at high risk of bias, so our results presumably overestimate benefit and underestimate harm. The quality of the evidence was very low.

Simeprevir with peginterferon α-2a/ribavirin for chronic hepatitis C virus genotype 1 infection in treatment-experienced patients: an open-label, rollover study

BACKGROUND

This Phase 3, open-label, rollover study (NCT01323244) investigated the efficacy and safety of simeprevir plus peginterferon α-2a (PegIFNα-2a) and ribavirin (RBV) in a well-characterized population of HCV genotype 1 (GT1)-infected treatment-experienced patients.

METHODS

Patients who had failed PegIFNα/RBV treatment in the placebo arm of a previous Phase 2/3 simeprevir study (Phase 2/3 group, n = 125), or had been exposed to HCV direct-acting antivirals (simeprevir or other) for up to 14 days in a selected Phase 1 study (Phase 1 group, n = 16), were eligible. Phase 2/3 group patients were classified according to prior relapse, breakthrough, or non-response (null response, partial response, non-classifiable non-response) to PegIFNα/RBV. Eight patients in the Phase 1 group received short-term (≤14 days) simeprevir. Treatment comprised simeprevir 150 mg once daily (QD) plus PegIFNα-2a/RBV for 12 weeks followed by PegIFNα-2a/RBV for 12 or 36 weeks (using response-guided therapy [RGT] to determine total treatment duration in Phase 2/3 prior relapsers or breakthrough) or 36 weeks fixed (Phase 2/3 group non-responders and Phase 1 group). The primary endpoint was sustained virologic response 12 weeks after planned end of treatment (SVR12).

RESULTS

Phase 2/3 group: SVR12 rate was 69.6% (87/125) overall; 92.7% (51/55), 60.0% (6/10), 64.3% (18/28), and 36.7% (11/30) in patients with prior relapse, viral breakthrough, partial response, or null response, respectively. SVR12 rates were similar for patients with HCV GT1a (66.0% [33/50]) and GT1b infection (72.0% [54/75]) and among HCV GT1a-infected patients with/without a baseline Q80K polymorphism (66.7% [8/12] and 65.8% [25/38], respectively). The majority of RGT-eligible patients (prior viral relapse or breakthrough) met RGT criteria (89.2% [58/65]); of these, 89.7% (52/58) achieved SVR12. Overall, 16.0% (20/125) of patients experienced on-treatment failure and 14.4% (18/125) experienced post-treatment failure (15 relapses, 3 missing data). Phase 1 group (simeprevir-naïve and -experienced patients combined): SVR12 rate was 37.5% (6/16). Safety and tolerability findings were comparable to those of the feeder studies.

CONCLUSIONS

The majority of RGT-eligible patients met criteria for shortening treatment to 24 weeks in total. Simeprevir 150 mg QD with PegIFNα-2a/RBV led to a high SVR rate among prior relapsers with HCV GT1 infection. No new safety signals were noted.

TRIAL REGISTRATION

NCT01323244 . (date of registration: March 24, 2011).

Effectiveness of interferon-free therapy for the treatment of HCV-patients with compensated cirrhosis treated through the Irish early access program

BACKGROUND

We investigated the real-world effectiveness of interferon-free regimens for the treatment of patients with compensated cirrhosis infected with hepatitis C virus (HCV).

METHOD

Using the Irish national HCV treatment registry, the effectiveness and safety of interferon-free regimens for HCV-infected patients treated between April 2015 and August 2016, was determined.

RESULTS

A SVR12 was achieved in 86% of subjects treated with sofosbuvir/ledipasvir ± ribavirin (SOF/LDV±RBV), 93% treated with paritaprevir, ombitasvir and ritonavir combined with dasabuvir ± ribavirin (3D±RBV) and 89% treated with sofosbuvir/daclatasvir ± ribavirin (SOF/DCV±RBV). The discontinuation rate was 5% and the on-treatment mortality rate was 1%.

CONCLUSION

The availability of interferon-free regimens represents a significant breakthrough for the treatment of HCV infection. Treatments options, with high SVR12 rates, are now available for patients with compensated cirrhosis who were unsuitable for treatment with interferon-based regimens. Data obtained from studies conducted in real world practice provide robust information fundamental for input into future economic evaluations for agents used for the treatment of HCV infection.

Medical and Behavioral Approaches to Engage People Who Inject Drugs Into Care for Hepatitis C Virus Infection

Direct-acting antivirals for hepatitis C virus infection may revolutionize treatment among persons with substance use disorders. Despite persons with substance use disorders having the highest hepatitis C virus prevalence and incidence, the vast majority have not engaged into care for the infection. Previously, interferon-based treatments, with substantial side effects and the propensity to exacerbate mental health conditions, were major disincentives to pursuit of care for the infection. Direct-acting antivirals with viral eradication rates of >90%, significantly improved side effect profiles, and shorter treatment duration are dramatic improvements over prior treatment regimens that should promote widespread hepatitis C virus care among persons with substance use disorders. The major unmet need is strategies to promote persons with substance use disorders engagement into care for hepatitis C virus. Although physical integration of treatment for substance use and co-occurring conditions has been widely advocated, it has been difficult to achieve. Telemedicine offers an opportunity for virtual integration of behavioral and medical treatments that could be supplemented by conventional interventions such as hepatitis C virus education, case management, and peer navigation. Furthermore, harm reduction and strategies to reduce viral transmission are important to cease reinfection among persons with substance use disorders. Widespread prescription of therapy for hepatitis C virus infection to substance users will be required to achieve the ultimate goal of global virus elimination. Combinations of medical and behavioral interventions should be used to promote persons with substance use disorders engagement into and adherence with direct-acting antiviral-based treatment approaches. Ultimately, either physical or virtual colocation of hepatitis C virus and substance use treatment has the potential to improve adherence and consequently treatment efficacy.

Mice Antibody Response to Conserved Nonadjuvanted Multiple Antigenic Peptides Derived from E1/E2 Regions of Hepatitis C Virus

Synthetic peptides are one of the hepatitis C virus (HCV)-specific small molecules that have antiviral activity and represent a target for HCV vaccine. This study aims to determine the lowest concentration of adjuvanted and non-adjuvanted (multiple antigenic peptide [MAP]) form of three conserved HCV envelope peptides that can induce murine immunogenic responses and evaluate the neutralization capacities of the generated antibodies (Abs) against HCV in cultured Huh7.5 cells. In this study, three HCV synthetic peptides, E1 peptide (a.a 315-323) and E2 peptides (a.a 412-419 and a.a 516-531) were synthesized. Female Balb/c mice were immunized with different concentration of either adjuvanted linear peptides or nonadjuvanted MAP peptides to determine the lowest dose that generates Ab responses enough to confer viral neutralization in vitro. The humoral responses targeting these peptides in immunized mice sera were measured by enzyme-linked immunosorbent assay (ELISA). Viral neutralization capacities of the generated mice Abs were assessed using Huh7.5 cells infected with the HCVcc infectious system (J6/JFH-1). The results of this study showed that the MAPs induce higher Ab titers than adjuvanted linear peptides after 4 weeks of immunization (p = 0.003). The viral neutralization experiments showed that the immunized mice sera contain anti E1/E2 Abs that blocked HCVcc (J6/JFH-1) entry into Huh7.5 cells. In conclusion, the three HCV envelope MAP peptides are more immunogenic and produce higher neutralizing Abs than linear peptides; therefore, they can be essential components for HCV vaccine.

Current therapy for chronic hepatitis C: The role of direct-acting antivirals

One of the most exciting developments in antiviral research has been the discovery of the direct-acting antivirals (DAAs) that effectively cure chronic hepatitis C virus (HCV) infections. Based on more than 100 clinical trials and real-world studies, we provide a comprehensive overview of FDA-approved therapies and newly discovered anti-HCV agents with a special focus on drug efficacy, mechanisms of action, and safety. We show that HCV drug development has advanced in multiple aspects: (i) interferon-based regimens were replaced by interferon-free regimens; (ii) genotype-specific drugs evolved to drugs for all HCV genotypes; (iii) therapies based upon multiple pills per day were simplified to a single pill per day; (iv) drug potency increased from moderate (∼60%) to high (>90%) levels of sustained virologic responses; (v) treatment durations were shortened from 48 to 12 or 8 weeks; and (vi) therapies could be administered orally regardless of prior treatment history and cirrhotic status. However, despite these remarkable achievements made in HCV drug discovery, challenges remain in the management of difficult-to-treat patients.

•

HCV genotype-specific drugs evolve to pan-genotypic drugs.

•

Drug potency increases from moderate (∼60%) to high (>90%) levels of sustained virologic response.

•

Treatment durations are shortened from a 48-week to 12-week or 8-week period.

•

HCV therapies based upon multiple pills per day are simplified to a single pill per day.

•

HCV therapies are administered orally regardless of prior treatment history and cirrhotic status.

Predictors of Early Discontinuation of Pegylated Interferon for Reasons Other Than Lack of Efficacy in United States Veterans With Chronic Hepatitis C

During the dual-therapy era, many patients with chronic hepatitis C discontinued therapy for reasons other than lack of efficacy (non-LOE). We determined whether selected patient characteristics predicted non-LOE discontinuation using national databases of U.S. veterans with Genotypes 1-4. We identified U.S. veterans in the Veterans Health Administration system in 2004-2009 who had hepatitis C-confirming RNA laboratory results and initiated therapy with pegylated interferon and ribavirin. We used a rule to classify patients who discontinued pegylated interferon early, based on pharmacy refill and viral response data. Multivariate Cox regression was used to identify predictors of non-LOE discontinuation. Of 321,238 patients with a hepatitis C International Classification of Diseases, Ninth Revision, code, 15,297 (4.8%) met all inclusion criteria. Non-LOE discontinuers comprised 30.3% of patients. For Genotypes 1-4, the predictors (adjusted hazard ratio) of greatest magnitude were comorbidities of myocardial infarction/congestive heart failure (1.36), renal disease (1.34), and platelets 100/mm or more (1.38). For Genotypes 2 and 3, predictors of greatest magnitude were Black race (1.30), myocardial infarction/congestive heart failure (1.84), albumin 3.5 mg/dl or more (1.65), sleep aid use (1.32), and poor persistence with antidepressants (1.31) and antihypertensive agents (1.37). Our study suggests that many host factors may have contributed to non-LOE dual-therapy discontinuation in veterans and may possibly predict non-LOE discontinuation in triple therapy.

Hepatitis C treatment: where are we now?

Chronic hepatitis C infection affects millions of people worldwide and confers significant morbidity and mortality. Effective treatment is needed to prevent disease progression and associated complications. Previous treatment options were limited to interferon and ribavirin (RBV) regimens, which gave low cure rates and were associated with unpleasant side effects. The era of direct-acting antiviral (DAA) therapies began with the development of first-generation NS3/4A protease inhibitors in 2011. They vastly improved outcomes for patients, particularly those with genotype 1 infection, the most prevalent genotype globally. Since then, a multitude of DAAs have been licensed for use, and outcomes for patients have improved further, with fewer side effects and cure rates approaching 100%. Recent regimens are interferon-free, and in many cases, RBV-free, and involve a combination of DAA agents. This review summarizes the treatment options currently available and discusses potential barriers that may delay the global eradication of hepatitis C.

Ribavirin revisited in the era of direct-acting antiviral therapy for hepatitis C virus infection

Over the past two decades, ribavirin has been an integral component of treatment for hepatitis C virus (HCV) infection, where it has been shown to improve the efficacy of (pegylated) interferon. However, because of treatment-limiting side effects and its additive toxicity with interferon, the search for interferon- and ribavirin-free regimens has been underway. The recent approvals of all-oral direct acting antivirals (DAAs) have revolutionized the HCV therapeutic landscape, and initially it was expected that the role of ribavirin with DAA regimens would be eliminated. On the contrary, what we have witnessed is that ribavirin retains an important role in the optimal treatment of some subgroups of patients, particularly those that historically have been considered the most difficult to cure. Fortunately, it has also been recognized that the safety profile of ribavirin is improved when co-administered with all-oral DAA combinations in the absence of interferon. Despite the antiviral mechanism of action of ribavirin being poorly understood, we now have a range of novel insights into the potential role of ribavirin in all-oral DAA HCV treatment and greater insight into the antiviral mechanism by which it continues to provide clinical benefit for defined patient groups.

Efficacy and direct costs of chronic hepatitis C treatment with first generation NS3/4A protease inhibitors in a real life population

Introduction

Recent years have brought a significant advance in chronic hepatitis C (CHC) treatment that includes development of direct acting antivirals (DAA). Two of them, boceprevir (BOC) and telaprevir (TVR), were first approved for treatment of patients infected with CHC genotype 1 in combination with pegylated interferon (P) and ribavirin (R). Our aim was to evaluate the efficacy and direct costs of BOC/PR and TVR/PR in a real life population.

Material and methods

The study included adult patients qualified for the CHC Therapeutic Programme treated with TVR/PR or BOC/PR. Treatment was continued for 24 or 48 weeks. Sustained virological response, treatment discontinuation due to adverse events and lack of virological response rates were compared.

Results

A total of 243 adult patients with CHC were included. TVR/PR and BOC/PR were administered in respectively 122 and 121 patients. Thirty-two patients (13%) were treatment-naïve, whereas liver cirrhosis/advanced fibrosis was observed in 138 patients (56.7%). Overall, 43.6% of patients achieved a sustained virologic response (SVR). In the BOC/PR group the SVR rate was significantly lower than in the TVR/PR group (33.1% vs. 54.1%; p = 0.00094). Lack of response to therapy was observed in 41.3% and 12.3% of patients receiving BOC and TVR, respectively (p < 0.00001). The direct cost of achieving SVR in one patient was 285 450 PLN with BOC and 185 757 PLN with TVR.

Conclusions

The very low treatment efficacy may be the result of inclusion criteria that allowed treatment of patients with advanced liver fibrosis/liver cirrhosis or previous treatment failure. Telaprevir seems to be significantly more potent against hepatitis C virus, with similar safety and tolerance.

Anti-hepatitis C virus drugs and kidney

Hepatitis C virus (HCV) mainly targets the liver but can also induce extrahepatic manifestations. The kidney may be impacted via an immune mediated mechanism or a cytopathic effect. HCV patients are clearly at a greater risk of chronic kidney disease (CKD) than uninfected patients are, and the presence of CKD increases mortality. Interferon-based therapies and ribavirin are difficult to manage and are poorly effective in end-stage renal disease and hemodialysis. These patients should be given priority treatment with new direct anti-viral agents (DAAs) while avoiding peginterferon and ribavirin. The first results were convincing. To aid in the correct use of these drugs in patients with renal insufficiency, their pharmacokinetic properties and potential renal toxicity must be known. The renal toxicity of these new drugs was not a safety signal in clinical trials, and the drugs are generally efficient in these frail populations. These drugs are usually well tolerated, but recent cohort studies have demonstrated that these new regimens may be associated with renal side effects, especially when using sofosbuvir combinations. HCV, renal diseases and comorbidities are intimately linked. The close monitoring of renal function is required, particularly for at-risk patients (transplanted, HIV-coinfected, CKD, hypertensive or diabetic patients). New DAA regimens, which will soon be approved, will probably change the landscape.

Do disparities between populations in randomized controlled trials and the real world lead to differences in outcomes?

AIM

To conduct a systematic review investigating reasons for the disparity between the efficacy and effectiveness rates reported in randomized controlled trials (RCTs) and observational studies of direct-acting antiviral treatment regimens licensed for use in genotype1 hepatitis C virus-infected individuals.

METHODS

This systematic review was conducted in accordance with the criteria of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses group.

RESULTS

Statistically significant (p < 0.05) differences in the baseline demographics and sustained virological response rates were observed between RCT and observational studies.

CONCLUSION

In order for outcomes from RCTs to be generalizable to the real world, greater consideration needs to be taken to include patient populations that are more representative of those awaiting treatment in the clinical setting.

Safe and effective sofosbuvir-based therapy in patients with mental health disease on hepatitis C virus treatment

AIM

To study impact of baseline mental health disease on hepatitis C virus (HCV) treatment; and Beck’s Depression Inventory (BDI) changes with sofosbuvir- and interferon-based therapy.

METHODS

This is a retrospective cohort study of participants from 5 studies enrolled from single center trials conducted at the Clinical Research Center of the National Institutes of Health, Bethesda, MD, United States. All participants were adults with chronic HCV genotype 1 infection and naïve to HCV therapy. Two of the studies included HCV mono-infected participants only (SPARE, SYNERGY-A), and 3 included human immunodeficiency virus (HIV)/HCV co-infected participants only (ERADICATE, PFINPK, and ALBIN). Patients were treated for HCV with 3 different regimens: Sofosbuvir and ribavirin in the SPARE trial, ledipasvir and sofosbuvir in SYNERGY-A and ERADICATE trials, and pegylated interferon (IFN) and ribavirin for 48 wk in the PIFNPK and ALBIN trials. Participants with baseline mental health disease (MHD) were identified (defined as either a DSM IV diagnosis of major depression, bipolar disorder, schizophrenia, generalized anxiety, and post-traumatic stress disorder or requiring anti-depressants, antipsychotics, mood stabilizers or psychotropics prescribed by a psychiatrist). For our first aim, we compared sustained virologic response (SVR) and adherence (pill counts, study visits, and in 25 patients, blood levels of the sofosbuvir metabolite, GS-331007) within each study. For our second aim, only patients with HIV coinfection were evaluated. BDI scores were obtained pre-treatment, during treatment, and post-treatment among participants treated with sofosbuvir-based therapy, and compared to scores from participants treated with interferon-based therapy. Statistical differences for both aims were analyzed by Fisher’s Exact, and t-test with significance defined as a P value less than 0.05.

RESULTS

Baseline characteristics did not differ significantly between all participants with and without MHD groups treated with sofosbuvir-based therapy. Among patients treated with sofosbuvir-based therapy, the percentage of patients with MHD who achieved SVR was the same as those without (SPARE: 60.9% of those MHD compared to 67.6% in those without, P = 0.78; SYNERGY-A: 100% of both groups; ERADICATE: 100% compared to 97.1%). There was no statistically significant difference in pill counts, adherence to study visits between groups, nor mean serum concentrations of GS-331007 for each group at week 2 of treatment (P = 0.72). Among patients with HIV co-infection, pre-treatment BDI scores were similar among patients treated with sofosbuvir, and those treated with interferon (sofosbuvir-based 5.24, IFN-based 6.96; P = 0.14); however, a dichotomous effect on was observed during treatment. Among participants treated with directly acting antiviral (DAA)-based therapy, mean BDI scores decreased from 5.24 (pre-treatment) to 3.28 during treatment (1.96 decrease, P = 0.0034) and 2.82 post-treatment. The decrease in mean score from pre- to post-treatment was statistically significant (-2.42, P = 0.0012). Among participants treated with IFN-based therapy, mean BDI score increased from 6.96 at pre-treatment to 9.19 during treatment (an increase of 2.46 points, P = 0.1), and then decreased back to baseline post-treatment (mean BDI score 6.3, P = 0.54). Overall change in mean BDI scores from pre-treatment to during treatment among participants treated with DAA-based and IFN-therapy was statistically significant (-1.96 and +2.23, respectively; P = 0.0032). This change remained statistically significant when analysis was restricted to participants who achieved SVR (-2.0 and +4.36, respectively; P = 0.0004).

CONCLUSION

Sofosbuvir-based therapy is safe and well tolerated in patients with MHD. A decline in BDI associated with sofosbuvir-based HCV treatment suggests additional MHD benefits, although the duration of these effects is unknown.

Network meta-analysis of first- and second-generation protease inhibitors for chronic hepatitis C genotype 1: efficacy based on RVR and SVR 24

PURPOSE

This study aimed to compare the efficacy among direct-acting antiviral agents (first and second-generation direct-acting antiviral agents (DAAs)) with placebo and with standard dual therapy (pegylated interferon + ribavirin (Peg-IFN + RBV)) in terms of rapid virologic response (RVR) and sustained virologic response (SVR) in chronic hepatitis C genotype 1 treatment.

METHODS

We performed a systematic review of randomized controlled trials (RCTs) in MEDLINE, International Pharmaceutical Abstracts, Cochrane Library, SCIELO, and Scopus and conducted a network meta-analysis to compare the efficacy of boceprevir (BOC), daclatasvir (DCV), grazoprevir, simeprevir (SMV) and telaprevir (TVR), in treatment-naive and treatment-experienced patients.

RESULTS

Sixteen studies encompassing 7171 patients were analysed. Associations between DAAs therapies (IFN-free regimens) could not be addressed since no common comparator was found in the RCTs among these associations and the other agents included in the present analysis. All agents were more efficacious than placebo or Peg-IFN + RBV in terms of RVR, while only BOC and SMV showed statistically significant superiority for the SVR outcome when compared to placebo or standard dual therapy. No significant differences between the DAAs were observed. The analysis prioritized treatment with DCV for both efficacy outcomes. Node-splitting analysis showed that our networks are robust (p > 0.05).

CONCLUSIONS

The superiority of DAAs over placebo or standard dual therapy with Peg-IFN + RBV was confirmed, indicating the greater efficacy of DCV. This study is the first network meta-analysis that included RVR as an outcome in the evaluation of these agents via indirect comparison. Further investigation should be carried out addressing safety and tolerability outcomes.

Effectiveness and tolerability of simeprevir and sofosbuvir in nontransplant and post-liver transplant patients with hepatitis C genotype 1

BACKGROUND

Hepatitis C virus genotype 1a (HCV-1a), prior treatment, cirrhosis and post-transplant status are historically associated with poor treatment responses. The new oral direct-acting agents appear to be effective and safe in these patients.

AIMS

To evaluate the effectiveness and tolerability of simeprevir and sofosbuvir in a diverse real-life cohort of patients, including difficult-to-treat patients.

METHODS

We conducted a retrospective cohort study in 198 consecutive patients with hepatitis C genotype 1 (148 nontransplant, 50 post transplant), who were treated with simeprevir and sofosbuvir for 12 weeks between December 2013 and December 2014. Primary outcome was sustained virological response with undetectable HCV RNA 12 weeks after completion of therapy (SVR12). Risk factors evaluated for lack of SVR12 included HCV 1a (vs. 1b), prior treatment (vs. none), and cirrhosis (vs. no cirrhosis).

RESULTS

SVR12 rates were similar in non- and post-transplant settings, 82% and 88%, respectively. There were no significant differences in adverse events in patients regardless of cirrhosis or transplant status. On multivariate analysis also inclusive of gender and liver transplant status, negative predictors of SVR12 were having at least 2 or 3 risk factors (OR 0.30, 95% CI 0.10-0.87, P = 0.027 or 0.29, 95% CI 0.09-0.85, P = 0.025, respectively).

CONCLUSION

Simeprevir and sofosbuvir combination is a safe and effective regimen for the treatment of non- and post-transplant patients with traditional risk factors for poor treatment response, unless more than 2 difficult-to-treat risk factors are present.

First and Foremost Battle the Virus: Eliciting Patient Preferences in Antiviral Therapy for Hepatitis C Using a Discrete Choice Experiment

BACKGROUND

There has been tremendous progress regarding treatment options for hepatitis C virus (HCV) infection. Several interferon-free regimens are awaiting regulatory approval. These innovations promise substantial reductions in the burden of disease and side effects as well as a decrease in treatment duration.

OBJECTIVES

The aim of this quantitaitive study was to elicit patient preferences for attributes of innovative antiviral therapies for hepatitis C.

METHODS

A systematic literature search and 14 semi-structured interviews were performed, resulting in eight patient-relevant characteristics. For the discrete choice experiment, an experimental design (3×3 + 5×6) was generated using Ngene software. The survey was conducted in August 2014 through computer-assisted personal interviews. The data were effects-coded in a random parameter logit estimation.

RESULTS

Participants were patients with HCV (N = 561; 58.1% men) in different treatment states. The analysis revealed a predominance of the attribute "reaching sustained virological response." When considering confidence intervals, the results showed three different preference ranks. At first place was "sustained virological response" (level difference [LD] 3.98), second was "anemia" (LD 1.10), followed by "number of interferon injections" (LD 0.92), "rash" (LD 0.82), "nausea and/or diarrhea" (LD 0.79), and "duration of antiviral therapy" (LD 0.78). The last position was occupied by both "tiredness/fatigue" (LD 0.31) and "headache" (LD 0.34).

CONCLUSIONS

From the patients' point of view, sustained virological response is the most essential criterion for choosing an HCV therapy. It was ranked at the highest, dominating all side effects and modes of administration. Furthermore, this study proved that patients consider both the probability of occurrence and the severity of treatment-induced side effects. Results clearly point to valuation of probabilities that is separate from that of severity.

Development of a rapid phenotypic test for HCV protease inhibitors with potential use in clinical decisions

Approximately 185 million people worldwide are chronically infected with hepatitis C virus (HCV). The first-wave of approved NS3 protease inhibitors (PIs) were Telaprevir and Boceprevir, which are currently discontinued. Simeprevir is a second-wave PI incorporated into the Brazilian hepatitis C treatment protocol. Drug resistance plays a key role in patients' treatment regimen. Here, we developed a simple phenotypic assay to evaluate the impact of resistance mutations in HCV NS3 protease to PIs, using a protein expression vector containing wild type NS3 protease domain and NS4A co-factor. We analyzed the impact of five resistance mutations (T54A, V36M, V158I, V170I and T54S+V170I) against Telaprevir, Boceprevir and Simeprevir. Protein purifications were performed with low cost methodology, and enzymatic inhibition assays were measured by FRET. We obtained recombinant proteases with detectable activity, and IC₅₀ and fold change values for the evaluated PIs were determined. The variant T54A showed the highest reduction of susceptibility for the PIs, while the other four variants exhibited lower levels of reduced susceptibility. Interestingly, V170I showed 3.2-fold change for Simeprevir, a new evidence about this variant. These results emphasize the importance of enzymatic assays in phenotypic tests to determine which therapeutic regimen should be implemented.

Combination of neutralizing monoclonal antibodies against Hepatitis C virus E2 protein effectively blocks virus infection

Hepatitis C virus (HCV) represents a major global health threat. The envelope glycoproteins, E1-E2 of HCV play an important role in infection by binding to hepatocyte surface receptors leading to viral entry. Several regions on the E1-E2 are conserved for maintaining structural stability, despite the high mutation rate of HCV. Identification of antigenic determinants in these domains would aid in the development of anti-virals. The present study was aimed to delineate neutralizing epitopes by generating monoclonal antibodies (mAbs) to envelope proteins that can block virus binding and entry. Using HCV-like particles (HCV-LPs) corresponding to genotype 3a (prevalent in India), we obtained three mAbs specific for the E2 protein that significantly inhibited virus binding to hepatoma cells. Using overlapping protein fragments and peptides of the E2 protein, the epitopes corresponding to the mAbs were delineated. MAbs H6D3 and A10F2 recognise sequential linear epitopes, whereas, mAb E3D8 recognises a discontinuous epitope. The epitope of mAb E3D8 overlaps with the CD81 receptor-binding site and that of mAb A10F2 with the hypervariable region 2 of the E2 protein. The epitopes corresponding to these mAbs are distinct and unique. A combination of these antibodies significantly inhibited HCV binding and entry in both HCV pseudoparticle (in vitro) and HCV cell culture (ex vivo) system compared to the mAbs alone (P<0.0001). In conclusion, our findings support the potential of employing a cocktail of neutralizing mAbs in the management of HCV infection.

Optimisation of triple therapy for patients with chronic hepatitis C: a systematic review

BACKGROUND

Triple therapy with Pegylated-Interferon α (PEG-IFNα)/Ribavirin (RBV) and Boceprevir (Boc) or Telaprevir (Tel) significantly improved sustained virological response (SVR) rates for patients with genotype 1 HCV infection compared to PEG-IFNα/RBV alone (dual therapy). However, less is known about factors associated with rates of SVR and of adverse events (AEs).

MATERIAL AND METHODS

The aim of this systematic review was to evaluate the evidence regarding the factors affecting response and rate of AEs associated with triple therapy. We performed systematic electronic searches in Medline, Embase, Scopus and Central as well as a list of reference literature. We included randomised controlled trials examining triple therapy compared with dual therapy and reporting data according to patients features and about AEs. Odds ratios (OR) were pooled using either fixed or random effect model, as appropriate.

RESULTS

We included data from 14 studies. Treatment with triple therapy increased SVR rate compared to dual therapy especially in patients previously treated with PEG-IFNα/RBV and with increased pretreatment alanine aminotransferase (ALT) levels. Higher rate of serious AEs and treatment discontinuation due to AEs was also observed particularly in treatment-experienced patients.

CONCLUSIONS

The present study shows how improved results of triple therapy are mainly observed in some patients' subsets and are accompanied by increased risk of AEs compared to dual therapy. These results might be useful for optimising treatment of chronic hepatitis C when IFN-free regimens are unavailable.

Retrospective Analysis of the Medication Utilization and Clinical Outcomes of Patients Treated with Various Regimens for Hepatitis C Infection

BACKGROUND

The hepatitis C virus (HCV) is the most common chronic blood-borne infection and the leading cause of liver transplantation in the United States. There are approximately 3.2 million people currently infected with HCV in the United States. In late 2013, the introduction of sofosbuvir and simeprevir represented a critical advancement in the treatment of HCV by improving sustained virologic response (SVR) rates.

PURPOSE

The purpose of this study was to evaluate medication utilization and clinical outcomes of patients with HCV who were treated with any Food and Drug Administration-approved combination of ribavirin, peginterferon products, simeprevir, and sofosbuvir.

METHODS

Prescription records and clinical assessment forms of patients who started HCV therapy and were eligible for SVR between January 1, 2014, and December 31, 2014, were retrospectively reviewed. Data collection included patient demographics, genotype, SVR, patient-reported adverse events, discontinuations, and adherence markers.

RESULTS

A total of 367 eligible patients were identified who had initiated treatment during the study period. Genotype 1 was the most common genotype, and an overall SVR rate of 86.9% was observed. Results were similar to those seen in phase III clinical trials. In addition, adverse events of these medications were more tolerable, and discontinuation rates were lower than with previous therapies.

25-OH vitamin D level has no impact on the efficacy of antiviral therapy in naïve genotype 1 HCV-infected patients

BACKGROUND AND AIM

The impact of 25-OH vitamin D on sustained viral response (SVR) to antiviral therapy and on fibrosis progression in hepatitis C is debated. We assessed the impact of 25-OH vitamin D concentration on the efficacy of antiviral therapy in naïve genotype 1 hepatitis C virus (HCV)-infected patients.

METHODS

The study population consisted of treatment-naïve genotype 1 patients enrolled in a randomised controlled trial. A total of 516 patients received peginterferon α-2a 180 µg/week plus ribavirin 800 mg/day for 24 weeks. There were 349 patients with undetectable HCV RNA (<50 IU/ml) at week 24 (W24) who were randomised to continue dual therapy (n = 173) or to continue peginterferon alone (n = 176) until week 48. 25-OH vitamin D concentration was measured at baseline in frozen serum.

RESULTS

A total of 461 patients could be analysed for virologic response at W24, and 285 (119 non-responders at W24 + 166 responders who continued dual therapy until W48) for the impact of SVR. There were 487 patients who could be analysed for fibrosis progression. Metavir fibrosis scores (centralised analysis) were: F1 30%, F2 34%, F3 27% and F4 9%. Median 25-OH vitamin D concentrations were similar in virologic responders (13.5 ng/ml) and in non-responders at W24 (12.6 ng/ml), as well as in patients with SVR (12.8 ng/ml) and without SVR (12.8 ng/ml, 3.99) at W72. Median 25-OH vitamin D concentrations were: F1: 14.30 ng/ml, F2: 13.50 ng/ml, F3: 13.30 ng/ml and F4: 12.80 ng/ml.

CONCLUSION

In this study, 25-OH vitamin D level has no impact on the efficacy of antiviral therapy in naïve genotype 1 HCV-infected patients.