Showing posts with label hcv abstracts. Show all posts
Showing posts with label hcv abstracts. Show all posts

Wednesday, August 23, 2017

Abstracts - Viral Hepatitis: Gastroenterological Society of Australia Australian Gastroenterology Week

Special Issue: Gastroenterological Society of Australia Australian Gastroenterology Week Precision Medicine in Gastroenterology, Gold Coast Convention & Exhibition Centre, Gold Coast, Queensland, 20–22 Aug 2017

Supplement
Journal of Gastroenterology and Hepatology
Abstracts of Gastroenterological Society of Australia Australian Gastroenterology Week
Volume 32, Issue Supplement S2 Pages 1 - 197, August 2017

Abstracts - Viral Hepatitis
Hepatitis-Viral (pages 65–86)
Version of Record online: 17 AUG 2017 | DOI: 10.1111/jgh.13892

Remote consultation referral system: An effective way to treat homeless and marginalized patients with chronic hepatitis C in primary care
Comparison of direct-acting antiviral therapy for hepatitis C between specialist centers and primary care: Efficacy and adherence to response assessment
Discontinuation of nucleoside analogue therapy in e-antigen-negative chronic hepatitis B: A meta-analysis
A real-world experience treating hepatitis C patients with direct-acting antivirals
Need for hepatocellular carcinoma screening during direct-acting antiviral treatment for patients with hepatitis C and cirrhosis
Project ECHO: A novel tele-mentoring service to aid hepatitis C treatment in difficult-to-access populations
Direct-acting antiviral therapy failures in hepatitis C treatment: A tertiary hospital's experience
Applying the REACH-B model to an Australian chronic hepatitis B cohort underestimates the incidence of hepatocellular carcinoma
General practitioners' perspectives on and use of remote consultation referral system for hepatitis C treatment in primary care: Interim results
Hepatitis C viral load at 12 weeks: Only half the story
References
Efficacy, safety, and long-term outcomes in hepatitis C virus genotype 1-infected patients receiving ombitasvir/paritaprevir/ritonavir and dasabuvir ± ribavirin: TOPAZ-I interim data from Australia
Early experience of direct-acting antiviral treatment for chronic hepatitis C in a needle syringe program outreach service
An eHealth model of care for community hepatitis c management: The HealthElink project
Characteristics and predictors of treatment failure for hepatitis C treatment in the first 12 months of unrestricted use of direct-acting antiviral therapy
Efficacy and outcomes of treatment with direct-acting antiviral therapy: An initial 12-month tertiary experience
Use of APRI to exclude cirrhosis in correctional services: Minimizing need for FibroScan
Mental health care in chronic hepatitis C patients: The unmet need in interferon-free treatment
References
Towards hepatitis C eradication in far north Queensland: A report on models of care and direct-acting antiviral outcomes
Defining a new phase in hepatitis B: The role of viral load in immune escape
Retrospective data analysis to assess the feasibility of transitioning the management of stable chronic hepatitis B from tertiary to primary care
Real-world treatment for hepatitis C in the direct-acting antiviral era: Comparing outcomes between the tertiary liver clinic and community
Outcomes of porphyria cutanea tarda in the era of direct-acting antivirals for hepatitis C infection
Effect of direct-acting antivirals on hepatocellular carcinoma incidence in hepatitis C virus-related cirrhosis
Liver clinic waiting time reduced with the introduction of remote support for hepatitis C treatment in primary care
Long-term outcomes of patients with chronic hepatitis B previously treated with pegylated-interferon
The first year with combination direct-acting antivirals in a real-world cohort from a regional liver clinic in New South Wales
References
Outcomes of treatment for hepatitis C virus infection in the prison setting
Direct-acting antiviral treatment failure is associated with genotype 3 hepatitis C cirrhosis and the selection of NS5A resistance sequences: Implications for salvage therapy
Preliminary results from the HEDGE study: Does the hepatitis C virus cause depression?
Role of point-of-care testing for hepatitis B in culturally and linguistically diverse communities
How well used, effective, and safe is general practitioner prescription of hepatitis C therapy?
Risk of hepatocellular carcinoma among patients with hepatitis C virus cirrhosis treated with direct-acting antiviral therapy: An Australian experience
Hepatitis C and liver disease in opioid treatment program patients
References
High efficacy in patients with chronic hepatitis C virus genotype 1b infection treated with elbasvir–grazoprevir for 12 weeks: An integrated analysis
Can quantitative HBsAg threshold predict high viral load and risk of mother-to-child transmission? Like life, you get what you pay for
“Teach-back” is a simple communication tool that improves health literacy in people with chronic hepatitis B
Chronic hepatitis B infection: 25 years of nucleoside analogue therapy
Real-world Australian data replicate very high sustained virological response at 12 weeks (SVR12) results reported in clinical trials and suggest SVR12 is highly achievable even in those without an end-of-treatment response
Eliminate Hepatitis C Partnership: Clinical site scoping
Quantitative HBeAg levels at Week 24 predict on-treatment serological response to tenofovir disoproxil fumarate therapy in HBeAg-positive patients infected with chronic hepatitis B
Hepatitis B virus activity does not influence the degree of liver steatosis in patients with hepatitis B-related chronic liver disease
References
Australian tertiary hospital real-life experience: Universal access to direct-acting antivirals in a novel treatment model 

Wednesday, January 11, 2017

Safety, tolerability, and antiviral effect of RG-101 in patients with chronic hepatitis C: a phase 1B, double-blind, randomised controlled trial

Source - NATAP

The Lancet
Safety, tolerability, and antiviral effect of RG-101 in patients with chronic hepatitis C: a phase 1B, double-blind, randomised controlled trial
Meike H van der Ree, MD, J Marleen de Vree, MD, Femke Stelma, MD, Sophie Willemse, MD, Marc van der Valk, MD, Svend Rietdijk, MD, Richard Molenkamp, PhD, Janke Schinkel, MD, Ad C van Nuenen, BSc, Prof Ulrich Beuers, MD, Salah Hadi, MD, Marten Harbers, PhD, Eva van der Veer, MSc, Kai Liu, PhD, John Grundy, PhD, Amy K Patick, PhD, Adam Pavlicek, PhD, Jacqueline Blem, BSc, Michael Huang, MD, Paul Grint, MD, Steven Neben, PhD, Neil W Gibson, PhD, Neeltje A Kootstra, PhD, Dr Hendrik W Reesink, MD

Published: 10 January 2017
DOI: http://dx.doi.org/10.1016/S0140-6736(16)31715-9
Summary
Background
miR-122 is an important host factor for hepatitis C virus (HCV) replication. The aim of this study was to assess the safety and tolerability, pharmacokinetics, and antiviral effect of a single dose of RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated oligonucleotide that antagonises miR-122, in patients with chronic HCV infection with various genotypes.

Methods
In this randomised, double-blind, placebo-controlled, multicentre, phase 1B study, patients were randomly assigned to RG-101 or placebo (7:1). We enrolled men and postmenopausal or hysterectomised women (aged 18–65 years) with chronic HCV genotype 1, 3, or 4 infection diagnosed at least 24 weeks before screening who were either treatment naive to or relapsed after interferon-α based therapy. Patients with co-infection (hepatitis B virus or HIV infection), evidence of decompensated liver disease, or a history of hepatocellular carcinoma were excluded. Randomisation was done by an independent, unblinded, statistician using the SAS procedure Proc Plan. The first cohort received one subcutaneous injection of 2 mg/kg RG-101 or placebo; the second cohort received one subcutaneous injection of 4 mg/kg or placebo. Patients were followed up for 8 weeks (all patients) and up to 76 weeks (patients with no viral rebound and excluding those who were randomised to the placebo group) after randomisation. The primary objective was safety and tolerability of RG-101. This trial was registered with EudraCT, number 2013-002978-49.

Findings
Between June 4, 2014, and Oct 27, 2014, we enrolled 32 patients with chronic HCV genotype 1 (n=16), 3 (n=10), or 4 (n=6) infections. In the first cohort, 14 patients were randomly assigned to receive 2 mg/kg RG-101 and two patients were randomly assigned to receive placebo, and in the second cohort, 14 patients were randomly assigned to receive 4 mg/kg RG-101 and two patients were randomly assigned to receive placebo. Overall, 26 of the 28 patients dosed with RG-101 reported at least one treatment-related adverse event. At week 4, the median viral load reduction from baseline was 4·42 (IQR 3·23–5·00) and 5·07 (4·19–5·35) log10 IU/mL in patients dosed with 2 mg/kg RG-101 or 4 mg/kg RG-101. Three patients had undetectable HCV RNA levels 76 weeks after a single dose of RG-101. Viral rebound at or before week 12 was associated with the appearance of resistance associated substitutions in miR-122 binding regions in the 5′ UTR of the HCV genome.

Interpretation
This study showed that one administration of 2 mg/kg or 4 mg/kg RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated anti-miR-122 oligonucleotide, was well tolerated and resulted in substantial viral load reduction in all treated patients within 4 weeks, and sustained virological response in three patients for 76 weeks.

Funding
Regulus Therapeutics, Inc.
http://www.thelancet.com/journals/lancet/onlineFirst

Tuesday, June 14, 2016

Outcomes in patients with chronic Hep C treated with different anti-viral regimens

Outcomes in patients with chronic Hep C treated with different anti-viral regimens

The latest issue of the American Journal of Gastroenterology performs an in-depth analysis of patient-reported outcomes in patients with chronic hepatitis C treated with different anti-viral regimens.

Interferon- and ribavirin-containing regimens negatively impact patients’ experience.

Dr Zobair Younossi and colleagues from Virginia, USA quantified the impact of different anti-viral regimens for hepatitis C on patients’ work productivity, fatigue, and other patient-reported outcomes.

The patient-reported outcome data from multicenter multinational phase 3 clinical trials of sofosbuvir with and without interferon or ribavirin were retrospectively used.

Treatment regimens were classified as interferon+ribavirin-containing, interferon-free ribavirin-containing, and interferon-free ribavirin-free.

The team administered 4 patient-reported outcome instruments to subjects at baseline, during, and up to 24 weeks after treatment.

Interferon was associated with up to −26% worsening of the patient-reported outcome scores
American Journal of Gastroenterology


The researchers included 3,425 subjects with chronic hepatitis C infection with patient-reported outcome data.

The team found that patients were 63% male, 62% treatment naive, 18% with cirrhosis, and 73% with HCV genotype 1.

Of the study participants, 546 received interferon+ribavirin+sofosbuvir, 1,721 received sofosbuvir+ribavirin, and 1,158 received interferon- and ribavirin-free ledipasvir+sofosbuvir.

At baseline, there were no difference in patient-reported outcomes between treatment groups.

During treatment, the decrements in patient-reported outcomes were up to −24% for the interferon+ribavirin group, up to −7% in the sofosbuvir+ribavirin group, whereas there was an improvement of up to +12% in the interferon-free ribavirin-free group.

The researchers found that use of interferon was independently associated with up to −26% worsening of the patient-reported outcome scores during treatment and the use of ribavirin with up to −9% worsening.

The team noted that after 12 weeks post-treatment, in patients with sustained virologic response-12, improvements were observed regardless of the regimen, and these improvements continued to increase by week 24 of follow-up.

Dr Younossi's team concludes, "The use of interferon- and ribavirin-free regimens for HCV is associated with better patients’ experience, and work productivity during treatment."

Am J Gastroenterol 2016; 111:808–816
14 June 2016

Tuesday, February 9, 2016

Hepatitis C virus: A time for decisions. Who should be treated and when?

Review
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Pharmacol Ther. Feb 6, 2016; 7(1): 33-40
Published online Feb 6, 2016. doi: 10.4292/wjgpt.v7.i1.33

Hepatitis C virus: A time for decisions. Who should be treated and when?
Bashar M Attar, David H Van Thiel Bashar M Attar, Cook County Health and Hospitals System, Rush University Medical Center, Chicago, IL 60612, United States David H Van Thiel, Advanced Liver and Gastrointestinal Disease Center, Berwyn, IL 60402, United StatesAuthor contributions: Both the authors contribute to collect of data, synthesis, and write of the manuscript.

Abstract Full Article (PDF) Full Article (WORD) Full Article (HTML)

Core tip: This study presents the burden of hepatitis C virus (HCV) infection. Current guidelines limit treatment to those with advanced liver disease (Metavir F-3 or F-4 fibrosis). This represents a small fraction of those infected having the worse prognosis. They are unlikely to infect others. In contrast, the much larger group F-0 to F-2 is the vectors for additional infections. The plague of HCV can only be eliminated if the larger groups that infect others are treated. The cost of treating this larger population is expensive but much less expensive than treating only those with advanced fibrosis in the long run.

Excerpt:

Finally, treating all HCV infected patients to include those with and without hepatic disease with DAA regimens will reduce the number of individuals developing advanced liver disease, reduce the cost of treating these cases and more importantly, reduce the cost of treatment of those with any form of HCV related disease to include not only those with F0-F2 fibrosis of the liver but also those with extra hepatic disease related to HCV infection with or without evidence for coexistent liver disease. 

Abstract
Cirrhosis is the most important risk factor for hepatocellular carcinoma (HCC) regardless of the etiology of cirrhosis. Compared to individuals who are anti-hepatitis C virus (HCV) seronegative, anti-HCV seropositive individuals have a greater mortality from both hepatic as well as nonhepatic disease processes. The aim of this paper is do describe the burden of HCV infection and consider treatment strategies to reduce HCV-related morbidity and mortality. The newly developed direct acting antiviral (DAA) therapies are associated with greater rates of drug compliance, fewer adverse effects, and appear not to be limited by the presence of a variety of factors that adversely affect the outcome of interferon-based therapies. Because of the cost of the current DAA, their use has been severely rationed by insurers as well as state and federal agencies to those with advanced fibrotic liver disease (Metavir fibrosis stage F3-F4). The rationale for such rationing is that many of those recognized as having the disease progress slowly over many years and will not develop advanced liver disease manifested as chronic hepatitis C, cirrhosis, and experience any of the multiple complications of liver disease to include HCC. This mitigation has a short sided view of the cost of treatment of hepatitis C related disease processes and ignores the long-term expenses of hepatitis C treatment consisting of the cost of treatment of hepatitis C, the management of cirrhosis with or without decompensation as well as the cost of treatment of HCC and liver transplantation.

We believe that treatment should include all HCV infected patients including those with stage F0-F2 fibrosis with or without evidence of coexisting liver disease. Specifically, interferon (IFN)-free regimens with the current effective DAAs without liver staging requirements and including those without evidence of hepatic diseases but having recognized extrahepatic manifestations of HCV infection is projected to be the most cost-effective approach for treating HCV in all of its varied presentations.

Early rather than later therapy of HCV infected individuals would be even more efficacious than waiting particularly if it includes all cases from F0-F4 hepatic disease. Timely therapy will reduce the number of individuals developing advanced liver disease, reduce the cost of treating these cases and more importantly, reduce the lifetime cost of treatment of those with any form of HCV related disease as well as HCV associated all - cause mortality. Importantly, HCV treatment regimens without any restrictions would result in a substantial reduction in health care expenditure and simultaneously reduce the number of infected individuals who are infecting others.
Keywords: Hepatitis C virus, Direct acting antivirals, Cirrhosis of the liver, Timing of treatment

INTRODUCTION

Chronic hepatitis C virus (HCV) infection is an important cause of advanced liver disease and liver-related deaths. The aim of this document is to describe the burden of HCV infection and consider treatment strategies to reduce HCV-related morbidity and mortality[1-5].

It is estimated that the incidence of hepatocellular carcinoma (HCC) in Europe and United States will peak at 2020 at which there will be 78000 new HCC cases in Europe and 27000 in the United States[6]. Cirrhosis is the most important risk factor for HCC regardless of the etiology and cirrhosis occurs in the background of 90% of cases of HCC[6].

These figures probably under estimate the actual prevalence of the disease HCV as they are based upon data that excludes groups at recognized highest risks for the infection. Despite these limitations relative to the current estimates of the disease prevalence, it is well recognized that 50%-85% of the patients infected with HCV and manifest a hepatic disease process develop a chronic hepatitis and 20%-25% of these cases progress to cirrhosis with 20% of this latter group progressing further to HCC[7-9].

RISK OF HCV INFECTION AND NEED FOR SCREENING

HCV infection has an increasing HCV-related mortality from 1.09 to 2.40 per 100000 person years in the United States from 1995 to 2004[10]. The predicted mortality of HCV related disease over a 20-year period is expected to continue to rise as more and more individuals, who are currently infected, will have their disease for many more years. As a result, the healthcare burden in direct and indirect costs related to HCV infection will continue to rise in the foreseeable future[10]. The detection of HCV RNA in serum identifies active cases manifested by replication of the virus. Lee et al[10] reported that 52%-80% of serum samples seropositive for anti-HCV have been reported to have detectable serum levels of HCV RNA. Importantly, anti-HCV seropositive individuals with detectable serum HCV RNA have an increased risk of dying from all causes, whereas the risk for anti-HCV seropositives with negative HCV RNA is similar to that of HCV seronegative individuals[9,10]. Indeed, 2394 deaths occurred in HCV positive individuals during an average follow-up period of 16.2 years. Compared to individuals, who are anti-HCV seronegative, anti-HCV seropositive individuals have a greater mortality from both hepatic as well as nonhepatic disease processes. The multivariate-adjusted hazard ratio [95% confidence interval (CI)] of 1.89 (1.66-2.15) for all causes of death in HCV seropositive individuals and 12.48 (9.34-16.66) for hepatic diseases, 1.35 (1.15-1.57) for extrahepatic diseases, 1.50 (1.10-2.03) for circulatory diseases, 2.77 (1.49-5.15) for nephritis, nephrotic syndrome, and nephrosis, 4.08 (1.38-12.08) for esophageal cancer, 8.22 (1.36-49.66) for thyroid cancer, and 4.19 (1.18-14.94) for prostate cancer. Thus, the presence of HCV seropositivity increases the risk of death from a wide array of extrahepatic disease processes. Moreover, anti-HCV seropositives with detectable HCV RNA levels have a significantly greater mortality risk for death due to both hepatic and extrahepatic diseases processes than do individuals who are anti-HCV seropositives but who are HCV RNA negative. These data imply that individuals with chronic hepatitis C having an active infection manifested by HCV-RNA positivity should benefit from antiviral treatment to reduce both their overall mortality as well as hepatic disease mortality risk[10].

Recently, the Center for Disease Control (CDC) has identified individuals born between 1945 and 1965 as well as veterans, males, people in low income groups, prisoners, those in various institutions, and African American as well as the Latino populations as being at higher risk for a HCV infection[11]. As the majority of infected individuals have little or no symptoms, they may never know that they are infected despite the fact that 75%-80% of them may develop a lifelong chronic infection that adversely affects their life quality as well as their longevity. Individuals in this latter group also include those who received plasma or blood transfusions prior to 1992, hemophiliacs, individuals on hemodialysis, organ transplant recipients, those who experience needle sticks as a result of illicit drug use or an occupational exposures and possibly those infected as a result of tattoos or the use of unsterile equipment for body piercing, children born of a hepatitis C positive mothers and those who practice unprotected or high risk sex with multiple partners (Table 1). Most importantly, these asymptomatic individuals can unknowingly transmit the disease to others, thereby perpetuating the disease process in society at large[11,12].

THERAPY AND ERADICATION OF HCV

Historically, the available therapeutic agents utilized for the treatment of chronic hepatitis C (interferon-based therapies) have had only limited success at the elimination of the disease with efficacy rates ranging between 20% and 40% manifested as a sustained viral response (SVR) 6 mo after a presumed end of treatment (EOT) course of therapy[12]. In addition, these historical treatment regimens were expensive in terms of their direct and indirect costs, albeit less so than the new direct acting antiviral agents and had numerous adverse effect that limited their acceptability by individuals, who would have been considered as appropriate candidates for therapy. Moreover, the use of IFN-based therapies are contraindicated in individuals with a variety of autoimmune disease processes, those with a clinically significant depressive disorders, and those with advanced coronary artery or cerebrovascular disease. In addition, IFN-therapies have limited efficacy in individuals with different viral genotypes as well as specific genetic as well as phenotypic characteristics that include variant IL28B polymorphisms, obesity, diabetes mellitus, ethnicity and coinfection with either HBV or HIV[13,14].

In contrast, the newly developed direct acting (DAA) antiviral therapies are administered orally and require less complex regimes. As a result, they are more readily acceptable. As a consequence of their enhanced acceptability and increased rate of drug compliance, they achieve a significantly greater efficacy rate, have fewer adverse effects and appear not to be limited by the presence of a variety of concurrent medical disease processes to include the aforementioned genetic and phenotypic characteristics that adversely affect the outcome of interferon-based therapies. It is expected that the newer 3rd generation DAAs soon to be approved by the Food and Drug Administration (FDA) are even more efficacious and are effective across all genotypes as compared to the current 2nd generation DAA agents (Table 2)[15,16].

By increasing the sustained virological response (SVR) to 90% or more from 2016 onward the number of treated cases in Belgium has been estimated to increase from 710 to 2050 in 2030 resulting in a reduction of the number of cases with cirrhosis, decompensated cirrhosis and HCC disease process which have high direct and indirect costs of care[17]. The new DAAs are reported to be most efficacious as compared to historical regimens with interferon when applied to F2-F4 cases. To obtain comparable outcomes with all cases ranging from those with F0-F4 fibrosis, 50% more cases would have to be treated, a number which would appear to be achievable with the greater acceptability and reduced frequency of adverse events associated with the newer agents. Additionally, a two-year delay in access to the DAAs has been estimated to increase HCV related morbidity and mortality by 15%. These data suggest that early rather than later therapy of HCV infected individuals would be even more efficacious than waiting particularly if it includes all cases from F0-F4 hepatic disease[17].

van der Meer et al[18] have shown in an inter­national, multicenter, long-term follow-up study from 5 large tertiary care hospitals in Canada and Europe consisting of 530 patients with chronic HCV infection, who started an interferon-based treatment regimen between 1990 and 2003, that the 10-year cumulative incidence rate of liver-related mortality or transplantation was 1.9% (95%CI: 0.0%-4.1%) with a prior SVR following treatment and 27.4% (95%CI: 22.0%-32.8%) without a SVR (P < 001). Thus, in patients with chronic HCV infection and advanced hepatic fibrosis, a sustained virological response to interferon-based treatment is associated with a lower all-cause mortality rate and obviously a substantial reduction in overall direct and indirect costs of healthcare.

Molnar et al[19] reported an association between HCV infection and the progression of chronic kidney disease. HCV infection was associated with a 2.2 fold increase in mortality, a 98% higher hazard of development of end-stage kidney, and a 15% worsening of renal function in a large cohort of United States veterans. In addition to death related to hepatocellular cancer, all-cause mortality increased with HCV infection was attributed in part to association with extrahepatic manifestations of HCV such as cryoglobulinemia, lymphoma, glomerlulonephritides, as well as rheumatologic, hematologic, and dermatologic disorders.

Simmons et al[20] reported in a meta-analysis and systematic review of 31 studies that achieving SVR in individuals with chronic HCV. After adjustment for potential confounding factors, the results of the pooled HR analysis revealed a decreased risk of all-cause mortality by approximately 50%, 74%, and 79% in the general populations, cirrhotic patients, and coinfected (HCV/HIV) individuals respectively.

Sievert et al[21] described three different treatment scenarios based upon the anticipated introduction of DAA regimens have been estimated to reduce the overall HCV disease burden. Scenario 1 evaluated the impact of increased treatment efficacy alone estimated to be 80%-90% by 2016. Scenario 2 evaluated the increased expected efficacy as well as the increase in numbers of individuals expected to be treated from a value of 2550 to 13500 by 2018 without any treatment restrictions. Scenario 3 considered the same increases in efficiency and number expected to be treated limited to those with fibrotic disease ≥ F3 during the period of 2015-2017. The authors estimated that 233490 people with chronic HCV infection. This group has included 13850 individuals with cirrhosis, 590 with HCC and 530 with liver-related deaths. Scenario 1 would result in a modest reduction in disease burden (4% decreases in HCC, decompensated cirrhosis, and liver deaths) and the overall costs related to these diseases. Scenario 3 had the greatest impact on disease burden projected at a 50% decrease in HCC, decompensated cirrhosis, and liver deaths and overall healthcare costs. Scenario 2 had only a slightly lower impact than did Scenario 3.

These data suggest that treatment regimens without any restrictions would result in a substantial reduction in health care costs and simultaneously reduce the number of infected individuals infected who can infect others (Table 3)[22,23].

The development of the second-generation protease inhibitors (PIs) had a higher antiviral efficiency as a result of their plurigenotypic range but also as they were more convenient to administer and were associated with fewer side effects[24]. The NS5B inhibitors include nucleoside/nucleotide inhibitors (NIs) and non-nucleotide inhibitors (NNIs). NIs have even higher efficacy rates and even more useful as they can be used across all genotypes.

Sofosbuvir has highly potent antiviral activity across all genotypes when used in association with pegylated interferon and ribavirin (PR). NS5A inhibitors (NS5A) also have potent antiviral activity and when used in combination with protease inhibitors are reported to achieve a SVR in GT-1b prior null responders to a prior interferon-based regimen. Several additional studies have demonstrated that interferon (IFN)-free regimens with DAA agent combinations achieve even higher rates of SVR in naïve as well as treatment-experienced GT-1 patients, who have failed prior interferon based treatment regimes. Moreover, quadruple regimens with peginterferon plus ribavirin (PR) achieve a SVR in almost all GT-1 null responders. The development of pan-genotypic direct-acting antiviral agents (NIs or NS5A.I) will allow additional new combinations with or without PR that are expected to increase the rate of SVRs for all patient populations regardless of genotype and those with cirrhosis[24].

COST OF HCV TREATMENT AND THE NEED FOR TIMELY THERAPY

In contrast to the recommendation for screening for HCV and the subsequent recognition of cases, the use of DAA therapy has been severely rationed by insurers as well as state and federal agencies. The cost of these drugs can be effectively reduced by an increase of the use of these agents to include all those patients infected with HCV rather than just those with advanced hepatic fibrosis[25,26]. The rationale for such rationing is that many of those recognized as having the disease will progress slowly over many years, many identified cases will not develop advanced liver disease manifested as advanced chronic hepatitis and cirrhosis (F3-4 cases) and experience any of the multiple complications of their liver disease requiring specific treatment[27-31].

This reasoning fails to recognize the non-hepatic consequences of hepatitis C infection and the adverse effects of these non-hepatic diseases on patient’s quality of life. This represents a short sided view of the cost of treatment of hepatitis C related disease (infections) and ignores the long-term costs of hepatitis C treatment consisting of the cost of treatment of cirrhosis, the cost of treatment of decompensated cirrhosis as well as the cost of treatment of HCC as well as the cost of liver transplantation and its long-term follow up. These costs far exceed the costs related to the treatment of hepatitis C before any of these complications occurs. In addition, this reasoning ignores the fact that hepatitis C infection is not limited to the liver per se and also includes a wide range of extra hepatic disease processes that occur in the absence of clinical liver disease and have extensive direct and indirect costs of their own (Table 4)[30-35]. These diseases affect adversely the individual’s life quality and potentially longevity[36-41]. Most importantly, the exclusion of cases with recognized hepatic disease ranging from those with F0 to F2 and those with extra hepatic disease processes fails to recognize that these individuals are the principal vectors for new cases of HCV infection[42-47]. Their treatment would be expected to greatly reduce the numbers of newly infected cases to include those with and without recognized hepatic disease and potentially eliminate the disease in the population at large[48-50].

The rationing of therapy to those with advanced liver disease, also calls into question the ethical consequences of the recommendations of the CDC and other health related organizations and societies to screen individuals for the disease if no treatment is to be made available to those identified as having the disease. To do so under these circumstances only produces anguish and inappropriate fear in those identified as having the infection[51].

The alternative approach of recognizing those that have the infection and treating them before they develop clinically evident disease associated with the tremendous costs to society in terms of direct and indirect costs of health care as a result of hepatic as well as the many extra hepatic disease processes known to occur as a result of hepatitis C infection should result in major long term reductions in health care costs[52]. Moreover, by treating these larger populations, the number of individuals, who unknowingly infect others and perpetuate the infection in the population, would be reduced with even greater overall health care cost reductions. The institution of this alternative approach incorporating a much larger population of infected individuals would make it possible for a marked reduction in cost per unit pill or course of therapy while maintaining the overall profit for pharmaceutical companies, who have expen­ded large amounts of money to bring the drugs to market[52,53].

Finally, at the day to day clinical level, treatment of patients with stages F0-F3 would be expected to be even more efficacious, be better tolerated with fewer cases dropping out of therapy than what would occur by delaying, treatment until more advanced stages of liver disease (cirrhosis, hepatic cancer, liver transplant) or not providing treatment at all[54].

Younossi et al[55] administered a questionnaire to 1923 individuals with chronic hepatitis C, genotype-1, who were enrolled in the ION trials and received HCV treatment of combination of ledipasvir and sofosbuvir (LDV/Sof) with a SVR-12 rate of 93.21%.Reduced work productivity secondary to absententeeism and presenteesim impairments dropped after achieving SVR-12 which would result in a productivity loss saving of 2.7 billion over one-year.

Tandon et al[56] using a health insurance claims database from January 2001 to March 2012, com­pared a total of 1017 patients, who completed interferon therapy and 953 patients, who discontinued therapy. Both resource utilization and healthcare cost statistically significant lower cost allocation of 3687 and 1644 dollars for all-causes and CHC-related healthcare costs, respectively, relative to those who discontinued therapy.

CONCLUSION

Many patients achieve a SVR with PEG-IFN containing therapies. The continued improvements in the ability to obtain a SVR (expected cure) of HCV have been made within the past several years. The principal reason to utilize DAAs is to avoid the side effects of IFN which enhances acceptability, compliance and efficacy of treatment. The enhanced efficacy of these agents and the shorter duration of therapy are additional benefits.

Secondly, considerable increases in the burden of HCV-related advanced liver disease and its com­plications are expected to be seen in the United States utilizing current treatment regimens. The introduction of improved DAA regimens with enhanced efficacy and a non-restricted requirement for treatment should result in an even greater impact on the total health care costs and reduce the life-long costs of HCV dis­ease management costs. A combination of increased treatment efficacy and greater utilization by treating all presentations of all the disease to include not only those with evident hepatic disease but also those without evidence of liver disease should result in major reductions in the lifetime costs of HCV related disease costs.

Finally, treating all HCV infected patients to include those with and without hepatic disease with DAA regimens will reduce the number of individuals developing advanced liver disease, reduce the cost of treating these cases and more importantly, reduce the cost of treatment of those with any form of HCV related disease to include not only those with F0-F2 fibrosis of the liver but also those with extra hepatic disease related to HCV infection with or without evidence for coexistent liver disease. Specifically, IFN-free regimens without liver staging requirements and including those without evidence of hepatic diseases but having recognized extrahepatic manifestations of HCV infection is projected to be the most cost-effective approach for treating HCV in all of its varied presentations. Therefore, treatment regimens without any restrictions would result in a substantial reduction in health care expenditure and simultaneously reduce the number of infected Individuals who are infected can infect others.

REFERENCES

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2 Bourlière M, Wendt A, Fontaine H, Hézode C, Pol S, Bronowicki JP. How to optimize HCV therapy in genotype 1 patients with cirrhosis. Liver Int 2013; 33 Suppl 1: 46-55 [PMID: 23286846 DOI: 10.1111/liv.12067]

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Footnotes
Conflict-of-interest statement: The authors declare no conflicts of interest regarding this manuscript.

Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/

Correspondence to: Bashar M Attar, MD, PhD, MPH, Cook County Health and Hospitals System, Rush University Medical Center, 1901 West Harrison Street, Chicago, IL 60612, United States.battar@rush.edu
Received: June 24, 2015
Peer-review started: June 24, 2015
First decision: August 3, 2015
Revised: September 16, 2015
Accepted: November 13, 2015
Article in press: November 17, 2015
Published online: February 6, 2016

Saturday, January 30, 2016

Chronic hepatitis C: This and the new era of treatment.

*Abstract, discussion and conclusion provided below please, click here to review the full text article. 

World J Hepatol. 2016 Jan 18; 8(2): 92–106.
Published online 2016 Jan 18. doi: 10.4254/wjh.v8.i2.92

Chronic hepatitis C: This and the new era of treatment.
Bertino G1, Ardiri A1, Proiti M1, Rigano G1, Frazzetto E1, Demma S1, Ruggeri MI1, Scuderi L1, Malaguarnera G1, Bertino N1, Rapisarda V1, Di Carlo I1, Toro A1,Salomone F1, Malaguarnera M1, Bertino E1, Malaguarnera M1.

Author information

Abstract
Over the last years it has started a real revolution in the treatment of chronic hepatitis C. This occurred for the availability of direct-acting antiviral agents that allow to reach sustained virologic response in approximately 90% of cases. In the near future further progress will be achieved with the use of pan-genotypic drugs with high efficacy but without side effects.

KEYWORDS:
Boceprevir; Daclatasvir; Dasabuvir; Direct-acting antiviral agents; Faldaprevir; Hepatitis C; Ledipasvir; Nucleoside inhibitors; Ombitasvir; Ritonavir; Simeprevir; Sofosbuvir; Telaprevir

Core tip: This review analyzes the current therapies for chronic hepatitis C and the future challenges of the research. So it tries to give an update on the research of hepatitis C virus (HCV) infection, providing a critical view of the emerging therapies and their impact on the future management of HCV infection. Since novel treatments for HCV infection are highly efficacious but costly, priority should be given to patients with advanced hepatic fibrosis, which is a disease that cannot be deferred.

DISCUSSION AND CONCLUSION 
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Today, it can be anticipated that the future of HCV infection treatment seems very bright after the addition of first-generation HCV PIs as well as SMV and the first-in-kind HCV RNA polymerase inhibitor, ‘‘sofosbuvir’’, in the standard of care (i.e., PEG-IFN/RBV). However, the real success of these drugs is very much dependent on careful monitoring of viral load and resistance, patterns of response to previous treatment, side effects and drug-drug interactions. Moreover, the logical meaning of novel emerging therapies must be to achieve high SVR and thorough clearance of the virus from treated patients. Nevertheless, the triple therapeutic regimens have several limitations. First, concomitant use of PEG-IFN plus RBV is essential to prevent the emergence of viral escape mutants and viral breakthrough during triple therapy. Second, triple therapy becomes less effective in prior null responders to PEG-IFN plus RBV and cannot be administered to patients who are contraindicated for PEG-IFN or RBV. To overcome these limitations, in the near future, many patients will be treated with two or more DAAs with or without IFN-α plus RBV based combination therapies. Currently, the approval of sofosbuvir- and SMV-based IFN-free regimens is an indication in this way. Triple and quadruple treatment regimens including multiple DAAs with or without PEG-IFN and RBV will likely be a suitable option for difficult-to-treat populations and for the prior null responders. All-oral IFN free regimens including drugs with a high genetic barrier to antiviral resistance (e.g., NS5B inhibitors) and high antiviral efficacy (e.g., NS3/4A PIs or NS5A inhibitors) may be a potent option for numerous patients contraindicated for PEG-IFN plus RBV. All oral regimens consisting of daclatasvir plus sofosbuvir once daily presented higher rates of SVR in untreated HCV GT-1, -2 and -3 infected patients and in HCV GT-1 infected patients who had failed previous treatment with PIs. We hope that such combinational treatment strategies will become ‘‘the weapon’’ to treat the majority of HCV infected patients who represent the difficult population (i.e., IL-28 polymorphism, HCV genotypes 1 and 4 subtypes, receipt of RBV, and the emergence of resistant variants) and will be more efficient to access the treatment in the near future. The testing of adenovirus vector based vaccines, which escalate the innate and acquired immune response against the most conserved regions of HCV genome in chimpanzees and humans, may be a promising therapeutic approach against HCV in the near future, although its fate still needs to be exploited fully in diverse HCV populations. One thing must be of special concern is whether the newly developed or being developed DAAs added in triple or quadruple therapies are safer or not than antiretroviral and traditional IFNs. Overall, the achievements in the field of HCV medicines may predict that we are near to complete elimination of HCV disease in the world[140]. The real challenges that our efforts must be directed are: (1) the effectiveness of IFN-free regimens in HCV-3, especially in cirrhotic non-responders; in this setting, combination with PEG-IFN is still possible; (2) the effectiveness of IFN-free regimens in decompensated cirrhosis are scarce in relation to the current correlation data between SVR and clinical outcome (literature confirms that the results of IFN-free regimens are good in compensated cirrhosis even if further clinical development is necessary in certain groups to improve SVR rates); (3) the development of new treatment strategies for patients who show resistance to new drugs; and (4) free-access to care[141]. In fact, many patients with CHC have mild disease and are currently excluded from the interferon-free treatment. In the near future we will inevitably prioritize this category in order to prevent progression to cirrhosis, decompensation and HCC.


Ribavirin: Past, present and future

World J Hepatol. 2016 Jan 18; 8(2): 123–130.
Published online 2016 Jan 18. doi: 10.4254/wjh.v8.i2.123
PMCID: PMC4716528
Ribavirin: Past, present and future
Véronique Loustaud-Ratti, Marilyne Debette-Gratien, Jérémie Jacques
Sophie Alain, Pierre Marquet, Denis Sautereau,Annick Rousseau, Paul Carrier
Author information ► Article notes ► Copyright and License information ►
Ribavirin: Past, present and future
Core tip: Ribavirin plays a crucial role when associated with peginterferon, preventing relapses and breakthroughs and doubling the support vector regression rate. Its antiviral effect is weak and ribavirin could enhance the response of interferon-stimulated genes in the combination. Ribavirin is still useful in the era of approved new direct acting antiviral agents (DAAs), in order to shorter treatment duration in genotype 1 or 4 cirrhotic patients, in all options available for genotype 3 cirrhotic patients, and as the only drug associated with sofosbuvir in genotype 2. Preliminary data with interferon-free second generation DAAs combinations without ribavirin suggest that future of the drug is jeopardized.

INTRODUCTION

Before the advent of direct acting antiviral agents (DAAs) ribavirin played a crucial role in the treatment of chronic hepatitis C associated to pegylated interferon[]. This combination is still relevant in many parts of the world which do not have access to new therapies because of cost issues[]. Although the role of ribavirin in the era of DAAs will probably decrease in the future with the arrival of second generation drugs, it remains essential in strategies decreasing treatment duration or in some difficult situations. The goal of this review is to briefly recall the recent past of ribavirin and consider its present and potential future.

RIBAVIRIN: MECHANISMS OF ACTION

So far, multiple mechanisms of action of ribavirin have been described. The antiviral mechanism is probably the best documented, the erroneous incorporation of ribavirin triphosphate into replicating RNA strands inhibiting chain elongation[]. In vitro, in the hepatitis C virus (HCV) RNA replication system, ribavirin reduces HCV replicon colony-forming efficiency in a dose-dependent manner, reinforcing this hypothesis[]. The inhibition via inosine monophosphate dehydrogenase of the de novo synthesis of GTP, required for the synthesis of viral RNA, is another but probably weak potential mechanism of action[]. However, the mutagenesis hypothesis remains controversial[]. The last most attractive mechanism of action is that ribavirin could enhance the response of interferon-stimulated genes making cells more sensitive to exogenous interferon and increasing the production of endogenous interferon[].
Two phases of plasma HCV RNA decline in patients treated with peginterferon and ribavirin have been described: A rapid first phase in the first two days[] reflecting the genesis and release of new virions and a slower second phase corresponding to the elimination of infected cells. The impact of the first-phase decline is weak (0.5 log) and goes unnoticed during double therapy, but is enhanced in patients treated with ribavirin alone[]. The second slope probably reflects the interferon-stimulated genes’ response and the production of endogenous interferon.
Multiscale models recently considered the possible effects of DAAs on intracellular HCV RNA production, degradation, assembly and secretion as virus into the circulation[]. The first-phase decline represents the viral clearance. The second represents the loss of intracellular viral RNA by export and degradation as well as the elimination of infected cells. The third represents a combination of the reduction in intracellular viral RNA production and the elimination of infected cells. Nowadays, there are no data available on the role of ribavirin in this setting, but we may imagine that ribavirin might impact the second- and the third-phase decline.

PAST OF RIBAVIRIN: COMBINATION THERAPY PEGINTERFERON AND RIBAVIRIN


Clinical history
Ribavirin, a guanosine analog is active against many DNA and RNA viruses and has clinical applications in respiratory syncytial infection in children, and Lassa Fever infection[,]. Di Bisceglie et al[] first showed that ribavirin could double the efficiency of standard alfa interferon. A similar synergy was observed with the association of peginterferon and ribavirin[,], ribavirin impacting favourably the number of relapses and breakthroughs[]. A total daily dose of ribavirin during the first three months > 10.6 mg/kg of body weight was predictive of sustained virological response (SVR)[,] and ribavirin had to be administered for the total duration of treatment[]. A pilot study also showed, that the use of high doses of ribavirin early during treatment led to high sustained virological rates[]. The same team proposed to optimize the dose of ribavirin using a formula based on renal function and body weight[].
Pharmacokinetics of ribavirin
Ribavirin is a drug typically adapted for therapeutic drug monitoring: Long half-life, large inter-individual variability of the dose-concentration relationship, and narrow therapeutic zone. After the first oral dose, a rapid absorption phase is observed with a maximum concentration at 1.5 h, followed by a rapid distribution phase (half-life of 3.7 h), and a long elimination phase of about 100 h post-dose[]. The monitoring of ribavirin plasma concentrations during double therapy initially used trough concentrations at week 4 and week 8 of treatment[,]. However, trough concentrations had a lower influence than the genotype and the viral load on SVR[].
We secondly showed that ribavirin plasma exposure after the first dose [i.e., measured by the interdose area under the concentration curve, area under the curve (AUC0-12h) or abbreviated AUC0-4h] was strongly linked to SVR and was probably a more relevant tool[]. Using receiver operating characteristic curve analysis, we defined an AUC0-4h threshold of 1755 μg/h per litre at day 0 as a target for ribavirin early dose adjustment, AUC0-4h being estimated using 3 blood samples (0.5, 1 and 2 h after the first dose) and Bayesian estimation. When comparing adapted and non-adapted patients with a suboptimal exposure to ribavirin at day 0 (i.e., D0 AUC0-4h < 1755 μg/h per litre), the difference of SVR reached nearly 30%, enhancing the benefit of adapted dose in this population (unpublished results).
Ribavirin and anemia during peginterferon and ribavirin treatment
Ribavirin-induced haemolytic anaemia is a frequent adverse event leading to drug discontinuation in 36% of the cases in real-life studies[], even if this anemia is reversible and dose-dependent. Medullar regeneration is partially prevented by various degrees of bone marrow suppression due to interferon impact. The prevalence of anaemia is high, with Hb level < 11 g/dL in 30% and < 10 g/dL in 9% to 13% of the patients[,] with 10% to 15% of the patients presenting with an Hb decline of more than 5 g/dL. Erythropoietin has been shown to improve the ribavirin treatment maintenance and tolerance[,] but did not prove its impact on SVR.
PRESENT OF RIBAVIRIN: TREATMENT WITH NEW DAAS
Interferon-free regimens DAAs currently approved by FDA and EMEA are used in combinations: Pangenotypic polymerase inhibitor sofososbuvir (Sovaldi®) associated with NS5A inhibitors ledipasvir (associated with sofosbuvir: Harvoni®) or daclatasvir (Daklinza®) (genotype 1, 3, 4), or with a protease inhibitor simeprevir (Olysio®) (genotype 1, 4); triple combination paritaprevir boosted with ritonavir (protease inhibitor), ombitasvir (NS5a inhibitor) (Viekirax®) and quadruple combination of paritaprevir, ritonavir, ombitasvir and dasabuvir (Exviera®) a polymerase inhibitor are also available for genotype 1, 4 patients.
Most of the time, these regimens give more than 90% SVR rate without the addition of ribavirin. However, ribavirin is still relevant in some circumstances.
Ribavirin and sofosbuvir alone are efficient in the treatment of most cases of G2 infected patients
Sofosbuvir and ribavirin combination is recommended in both European Association for the Study of the Liver (EASL) and French guidelines in G2 patients for 12 wk mainly[] except for cirrhotic experienced-patients (24 wk)[]. In this particular population, the only way to reduce treatment duration to 12 wk with similar SVR (95% to 100%) is to add peginterferon[,].
Nowadays, ribavirin remains essential for the last difficult-to-treat cirrhotic G3 patients
HCV G3 patients were first treated with sofosbuvir and ribavirin for 24 wk in phase III trials; response rates were 91% in patients without cirrhosis and only 68% in patients with cirrhosis, respectively[]. Recently, the Boson study showed the potential superiority of a peginterferon sofosbuvir and ribavirin regimen for 12 wk with a 91% to 86% SVR in naive and pre-treated cirrhotic patients respectively[]. Another strategy using sofosbuvir daclatasvir without ribavirin for 12 wk in G3 cirrhotic patients led to a weak 63% rate of SVR[]. Results of the French initial authorization for new DAAs are in favour of a 24-wk treatment but the sofosbuvir daclatasvir and ribavirin strategy for 12 wk was not available[]. This option could be a pertinent alternative to the 24-wk sofosbuvir daclatasvir association. Currently, EASL and French expert advices recommend treating patients with sofosbuvir daclatasvir for 24 wk, in the absence of the results of a new trial evaluating sofosbuvir daclatasvir ribavirin for 12 wk.
To sum up, all options currently available for cirrhotic G3 patients contain ribavirin and we have to wait for the results of new associations like sofosbuvir and the pangenotypic GS 5816 (astral 3 waiting results) or more sophisticated triple strategies like grazoprevir elbasvir and sofobuvir[].
Ribavirin is still necessary for G1a patients treated with ritonavir-boosted paritaprevir, ombitasvir and dasabuvir
The approval of the triple combination of ritonavir-boosted paritaprevir, ombitasvir and dasabuvir in patients infected with G1 was supported by six phase III clinical trials. In PEARL-IV, in patients infected with subtype 1a, the SVR rates were 97% and 90% with and without ribavirin respectively, suggesting that, unlike for G1b, ribavirin is needed in the 12-wk regimen for this subtype[]. Moreover, considering treatment-experienced cirrhotic patients with subtype 1a infection a 24 wk-treatment duration with ribavirin was needed[].
Reducing treatment duration to 12 wk in G1 or G4 cirrhotic patients is feasible thanks to ribavirin
In compensated and decompensated cirrhosis: Recent data suggest that the addition of ribavirin allows the treatment duration to be limited to 12 wk in patients with advanced liver disease, including patients with compensated cirrhosis (especially if they are treatment-experienced), patients with decompensated cirrhosis and subjects in pre- and post-liver transplant setting.
Twelve weeks with ribavirin or 24 wk without ribavirin are equivalent in compensated cirrhosis: In the Sirius study[], ledipasvir-sofosbuvir plus ribavirin for 12 wk and ledipasvir-sofosbuvir for 24 wk provided similar high SVR12 rates in previous non-responders with HCV G1 and compensated cirrhosis. The shorter regimen, when given with ribavirin, might, therefore, be useful to treat experienced patients with cirrhosis in case of no contra-indications to ribavirin.
Of note, in cirrhotic pre-treated patients with platelet count < 75000/mm3, the SVR rate is suboptimal (84%)[] and EASL guidelines recommend to extend the ribavirin-associated regimen to 24 wk in this subgroup.
In a post-hoc analysis of data from seven clinical trials which evaluated the efficacy and safety of the fixed-dose combination of ledipasvir and sofosbuvir, with and without ribavirin in 513 treatment-naive and previously treated patients with G1 HCV compensated cirrhosis, Reddy et al[] suggested the usefulness of ribavirin in the subpopulation of treatment-experienced patients receiving 12 wk of treatment (SVR12 rate of 90% vs 96% with ribavirin).
Finally in the hepather cohort[], difficult-to treat G1 (88% cirrhotics) patients receiving sofosbuvir daclatasvir and ribavirin achieved a SVR4 of 100% not different from sofosbuvir daclatasvir for 24 wk (SVR4 95%). In a multivariate analysis, factors associated with SVR in cirrhotics were the addition of ribavirin (OR = 6.3; P = 0.057) and a treatment-duration of 24 wk (OR = 4.3; P = 0.008).
Similarly, results from the same cohort study showed a benefit in the pre-treated cirrhotic population infected with G4 and receiving sofosbuvir daclatasvir or sofosbuvir simeprevir, with ribavirin[].
Same results are observed in decompensated cirrhosis in the pre and post-transplant setting except for Child Pugh C patients: The association of sofosbuvir ledipasvir and ribavirin for 12 wk in the pre and post transplant setting led to more than 85% to 95% SVR in cirrhotic patients[,]. However, in one study, the response rate was much lower (under 60%) in Child Pugh C patients suggesting a prolongation of treatment course to 24 wk[].
In non-cirrhotic G1 patients, ribavirin does not help to reduce treatment duration under 8 wk
Among previously untreated patients with HCV G1 infection and without cirrhosis in the phase III ION 3 study, the 8-wk ledipasvir-sofosbuvir regimen showed no inferiority to the 12-wk regimen[]. One interesting hypothesis could have been to further reduce the treatment duration by adding ribavirin to the combination.
However, in the electron study, among treatment-naive patients receiving 6 wk of sofosbuvir, ledipasvir and ribavirin, only 17 of 25 (68%) achieved an SVR12. The addition of ribavirin in this setting does not seem to be an appropriate strategy[].
Retreating patients with acquired anti NS5A resistance-associated variants using ribavirin-based strategies could be useful
In Reddy’s study[], 91% of G1 cirrhotic patients with NS5A resistance-associated variants (RAVs) at baseline and treated with sofosbuvir-ledipasvir achieved SVR12 (95%CI: 84-96), as compared with 98% (407 of 417) of those without baseline NS5A RAVs (95%CI: 96-99). This difference appeared to be mitigated by the addition of ribavirin to the regimen (88% of SVR without vs 94% with ribavirin).
The addition of ribavirin with DAAs combinations leads to more frequent but mild adverse events
In the main studies comparing interferon-free DAAs combinations with or without ribavirin for 12 wk, adverse events (AEs) were significantly higher (about 10%) when ribavirin was included in the strategy: Particularly fatigue, insomnia, pruritus, cough and of course all grades of anemia but only 5% of grade 3 and 4. Treatment discontinuation due to AEs (4%) was slightly more frequent. However, these AEs were not significantly higher in compensated cirrhotic patients when a 12-wk regimen with ribavirin was compared to a 24-wk regimen without ribavirin[]. Erythropoietin (EPO) was not used except in advanced cirrhotic disease and reduction of ribavirin dosage (9%) was most of the time sufficient with no impact on SVR[].
Of course, these AEs were more tolerable than in regimens including interferon, and even more than in triple therapy with first generation protease inhibitors.
There is probably no more place for ribavirin dose adjustment during treatment with DAAs
In the NIAID SPARE trial, Rower et al[], showed that ribavirin-monophosphate concentrations in red blood cells at day 14 were related to anaemia and SVR. A therapeutic range was identified for ribavirin-monophosphate in persons with HCV G1 disease receiving 24 wk of sofosbuvir plus ribavirin, suggesting a potential pharmacological basis for individualized ribavirin dosing in this interferon-free regimen. However, Jacobson et al[] showed in cirrhotic G1 patients, that ribavirin dose reduction due to anemia in the triple Abbvie combination (10% of the cohort) did not impact the SVR. One may hypothesize that the monitoring of ribavirin dose in G1 patients will not be useful when using at least two very potent new DAAs, unlike what was observed with the association of peginterferon and ribavirin or sofosbuvir and ribavirin.

FUTURE


Preliminary data with second generation interferon-free DAAs combinations without ribavirin suggest that ribavirin future is jeopardized even in difficult-to-treat patients
New double combinations: Grazoprevir elbasvir without ribavirin for 12 wk is efficient in difficult-to-treat G1 and G4 patients. In a phase II study (C-Worthy), high SVR12 rates were achieved irrespective of the use of ribavirin or of the extension of treatment duration from 12 to 18 wk in two cohorts of G1 patients, i.e., cohort 1, naive cirrhotic patients and cohort 2 previous null responders with or without cirrhosis. The SVR rate without ribavirin was 97% and 91% in the two cohorts respectively[]. In the Edge study, considering G1 and 4 patients (35% cirrhosis), the association of grazoprevir elbasvir gave similar results with and without ribavirin for a 12- or 16-wk duration (92% to 97%). Interestingly however, SVR rates were higher for the 16 wk + ribavirin arm regardless the status of the patient, the presence of cirrhosis and the presence of NS5A mutation (97%)[] suggesting a small residual role of ribavirin. In a phase II preliminary study, the same combination without ribavirin was effective and well tolerated in G1 Child B-cirrhotic patients[] leading to a 90% SVR. The combination of grazoprevir and elbasvir was useless or suboptimal for G3 and G2 patients respectively even with the addition of ribavirin and G5 patients, interestingly, still needed ribavirin[,].
The sofosbuvir GS-5816 (pangenotypic NS5a inhibitor) combination without ribavirin was clearly efficient in G3 non cirrhotic patients (100% SVR) and more efficient than other previous combinations in experienced cirrhotic patients (88%). However in the latter case, the addition of ribavirin seemed to bring a mild benefit (96% of SVR)[].
Multiple DAAs combinations without ribavirin in difficult-to-treat patients: In G1 naive or pre-treated cirrhotic patients, the association of daclatasvir NS5A pangenotypic inhibitor, asunaprevir NS3 protease inhibitor and beclabuvir NS5B non nucleosidic polymerase inhibitor without ribavirin, gave high response rates in naive patients (93%). However, ribavirin could still be useful in pre-treated patients (93% vs 87% SVR with and without ribavirin, respectively)[].
In G3 cirrhotic patients, preliminary results showed that the association of grazoprevir elbasvir sofosbuvir without ribavirin gave a 91% SVR suggesting that this combination could be an ideal strategy for these difficult to treat population[]. Of course, these results have to be confirmed.
Renal insufficiency: It will be soon possible to avoid ribavirin
Ribavirin use is problematic in this setting due to the management of severe anemia and the delicate dose adjustment which is not standardized (200 mg × 3/wk to 200 mg/d) and requires ribavirin concentration measurement especially in hemodialysis.
Today, no DAA association is recommended in patients with estimated glomerular filtration rate < 30 mL/mn, especially because the key tool of the approved associations, sofosbuvir and its main metabolite are eliminated by the kidney and the appropriate dosing is not known. Preliminary studies however showed that the simeprevir sofosbuvir (200 mg/d) association without ribavirin gave a SVR rate of 88% to 100% with a quite good tolerance[,].
The paritaprevir/ritonavir ombitasvir dasabuvir combination was also very efficient (100% response) but G1a subtype still needed ribavirin[].
Finally, in the largest study so far, out of 226 G1 patients with severe renal insufficiency, 191 with chronic kidney disease stage 5 and 179 hemodialysed showed a 99% SVR when treated with grazoprevir elbasvir for 12 wk without ribavirin with an excellent tolerance[].
These encouraging results will probably lead us to treat hemodialysed patients if no transplant perspective is envisaged, or before kidney transplantation, as HCV negatively impacts these patients’ prognosis.

CONCLUSION

Even if new DAAs are cost-effective, at their current prices, they are not cost-saving, and the addition of ribavirin with approved DAAs interferon-free regimens is probably the best option to decrease treatment duration without impacting SVR. The next step of course is one pill of DAAs a day without ribavirin to treat all patients whatever the stage of the disease or the genotype, with no side effects and for the shortest treatment duration possible. Even if second generation drugs do not yet fulfil all the criteria and probably will not for the next 5 years, they dangerously jeopardize ribavirin future.

ACKNOWLEDGMENTS

We thank Céline Rigaud for her help and Sarah Demai for her proofreading of English.

Footnotes

Conflict-of-interest statement: The authors have no conflict of interest concerning this work.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Peer-review started: September 5, 2015
First decision: October 16, 2015
Article in press: January 4, 2016
P- Reviewer: Mattner J, Rajeshwari K, Urganci N S- Editor: Qiu S L- Editor: A E- Editor: Liu SQ

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