Hepatitis C Virus: Current and Evolving Treatments for Genotype 4

Information and consensus document for the detection and management of chronic kidney disease

Chronic kidney disease (CKD) is a major public health problem worldwide that affects more than 10% of the Spanish population. CKD is associated with high comorbidity rates, poor prognosis and major consumption of health system resources. Since the publication of the last consensus document on CKD seven years ago, little evidence has emerged and few clinical trials on new diagnostic and treatment strategies in CKD have been conducted, apart from new trials in diabetic kidney disease. Therefore, CKD international guidelines have not been recently updated. The rigidity and conservative attitude of the guidelines should not prevent the publication of updates in knowledge about certain matters that may be key in detecting CKD and managing patients with this disease. This document, also prepared by 10 scientific associations, provides an update on concepts, clarifications, diagnostic criteria, remission strategies and new treatment options. The evidence and the main studies published on these aspects of CKD have been reviewed. This should be considered more as an information document on CKD. It includes an update on CKD detection, risk factors and screening; a definition of renal progression; an update of remission criteria with new suggestions in the older population; CKD monitoring and prevention strategies; management of associated comorbidities, particularly in diabetes mellitus; roles of the Primary Care physician in CKD management; and what not to do in Nephrology. The aim of the document is to serve as an aid in the multidisciplinary management of the patient with CKD based on current recommendations and knowledge.

Treatment with Grazoprevir/Elbasvir in Post-kidney Transplant Patients with Hepatitis C Virus Genotype 4 Infection

Background: Kidney transplant (KT) recipients have a high rate of hepatitis C virus (HCV) infection, which can impact long-term graft and patient survival rates. Although direct-acting antivirals (DAAs) are effective for treating HCV, there is limited data on their use in post-KT patients with HCV genotype 4 infection. Objectives: To evaluate the effectiveness and occurrence of adverse events with grazoprevir/elbasvir combination treatment without ribavirin in post-KT patients with HCV genotype 4 infection. Methods: In this case series, nine therapy-naïve adult post-KT patients with HCV genotype 4 infection were recruited. They had stable graft function and received a fixed dose of grazoprevir/elbasvir (50 mg/100 mg) combination without ribavirin daily for 12 weeks. Patients co-infected with hepatitis B virus, HIV, or with evidence of decompensated liver disease were excluded from the study. Patients were monitored for viral load, laboratory values, and adverse events associated with drug treatment. The response was defined by the sustained virologic response at 12 weeks (SVR12) after the end of treatment. Results: All nine patients completed the treatment period and achieved SVR12 with no treatment failure or relapse. Of them, six patients had HCV genotype 4 infection alone, and three had HCV of mixed genotypes 1 and 4. Two (22%) patients showed a rapid HCV clearance at four weeks. No adverse events or serious adverse events were reported. The patients’ renal function was stable during and after the treatment with no deterioration of graft function, and no adjustments to the immunosuppressive therapy were required. Conclusions: Grazoprevir/elbasvir combination without ribavirin is an effective and safe treatment option for post-KT patients with genotype 4 HCV infection.

Innate Immunity in Hepatitis C Virus Infection

Activation and viral control of the innate immune response are hallmarks of hepatitis C virus (HCV) infection and are major determinants of spontaneous clearance or progression to chronic infection and liver disease. In this review, we provide a contemporary overview of how HCV is sensed by the host cell to trigger innate immune activation and the mechanisms deployed by the virus to evade this response. Type I and III interferons (IFNs) are crucial mediators of antiviral innate immunity against HCV, and we specifically highlight the importance of IFN-λ host genetics for the outcome of HCV infection. Last, we focus on the proinflammatory responses elicited by HCV infection and describe our current understanding of how interleukin (IL)-1β signaling and cross talk between the IL-1β and IFN signaling pathways lead to sustained inflammation and increased risk of liver pathology.

Ombitasvir/paritaprevir/ritonavir plus ribavirin for 24 weeks in patients with HCV GT4 and compensated cirrhosis (AGATE-I Part II)

BACKGROUND AND AIMS

AGATE-I Part I previously reported high sustained virologic response rates in hepatitis C genotype 4 patients with cirrhosis, with 12 and 16 weeks' treatment with a combination of two direct-acting antivirals, ombitasvir and paritaprevir (codosed with ritonavir), plus ribavirin. Part II, reported here, extended the trial to include a 24-week treatment arm to fully assess treatment duration in patients with chronic hepatitis C genotype 4 infection and compensated cirrhosis.

METHODS

Enrollment took place between June and November of 2015. Treatment-naive and interferon-experienced patients with chronic hepatitis C genotype 4 infection and compensated cirrhosis were enrolled into Arm C; patients previously treated with a sofosbuvir-based regimen were enrolled into Arm D. All patients received a 24-week treatment with ombitasvir, paritaprevir, and ritonavir plus ribavirin. The primary outcome was the proportion of patients with a sustained virologic response (hepatitis C virus RNA < 25 IU/mL) at posttreatment week 12 in the intention-to-treat population. The safety population included all patients who received at least one dose of study drug.

RESULTS

In total, 64 patients were enrolled into AGATE-I Part II. Sustained virologic response at posttreatment week 12 was achieved in 57 of 61 patients (93.4%; 97.5% confidence interval, 92.6-97.7) in Arm C and 3 of 3 patients (100%) in Arm D. Two patients were missing SVR12 data, and two prematurely discontinued treatment. The most common adverse events for Arm C were fatigue (16 [26%]) and asthenia (15 [25%]). Results were comparable with those reported in Part I.

CONCLUSIONS

AGATE-I Part II indicates that extending treatment beyond 12 weeks in genotype 4-infected patients with compensated cirrhosis does not offer additional benefit.

Efficacy of elbasvir and grazoprevir in participants with hepatitis C virus genotype 4 infection: A pooled analysis

BACKGROUND & AIMS

The aim of this integrated analysis was to assess the efficacy of the once-daily combination of elbasvir 50 mg and grazoprevir 100 mg, with and without ribavirin in HCV genotype 4 (GT4)-infected participants enrolled in the Phase 2/3 clinical programme with elbasvir/grazoprevir.

METHODS

Treatment-naïve and treatment-experienced participants 18 years of age or older with chronic HCV GT4 infection and baseline HCV RNA ≥10 000 IU/mL were included in the analysis. The analysis population was the full analysis set (FAS; all participants who received at least 1 dose of study medication) and a total of 155 HCV GT4 participants were evaluated. The primary endpoint was sustained virologic response at week 12 (SVR12; HCV RNA less than the lower limit of quantitation at 12 weeks after the completion of study therapy).

RESULTS

Overall, among GT4-infected participants treated with 12 or 16 weeks of elbasvir/grazoprevir ± ribavirin, the SVR12 efficacy rates were 96.4% (107/111) in treatment-naïve participants and 88.6% (39/44) in treatment-experienced participants. The SVR12 rates were 96.0% (97/101) in treatment-naïve participants treated with 12 weeks of elbasvir/grazoprevir and 100% (8/8) in treatment-experienced participants treated with 16 weeks of elbasvir/grazoprevir plus ribavirin. Efficacy was not impacted by GT4 subtype.

CONCLUSIONS

The regimens of 12 weeks of elbasvir/grazoprevir without ribavirin, and 16 weeks of elbasvir/grazoprevir plus ribavirin, were efficacious in HCV GT4-infected treatment-naïve and treatment-experienced participants respectively. Baseline NS5A resistance-associated substitutions did not impact the efficacy of elbasvir/grazoprevir in GT4-infected participants.

Eliminating hepatitis C within low-income countries - The need to cure genotypes 4, 5, 6

Around 70 to 100 million people are chronically infected with HCV worldwide. HCV antiviral drug development has revolutionised the treatment of HCV, with several direct-acting antiviral agents offering patients the chance of cure after only 8-12 weeks of treatment. Drug development was initially focussed on HCV genotype 1 (GT1) infection, since this was the most prevalent worldwide, although clinical trials included all genotypes prevalent in the US and Europe. Because the earliest in vitro assays utilised the GT1b and 2 replicons, the initial classes of direct-acting antivirals (protease inhibitors, non-nucleotide polymerase inhibitors) were GT1-specific, albeit they had an effect on other less prevalent genotypes. Epidemiological data has shown the regional importance of other HCV genotypes. More than 50% of all HCV infections around the globe are not with GT1. The prevalence of HCV genotype 4 (GT4), 5 (GT5), and 6 (GT6) is increasing in North America and Europe due to migration from the Middle East, Africa and South-East Asia. With the successful development of the multi and pan-genotypic non-structural protein 5A inhibitors, second generation protease inhibitors and nucleotide non-structural protein 5B inhibitors comes a unique opportunity to achieve global HCV elimination. The goal of this review is to summarise the available information pertaining to GT4, GT5 and GT6, with a specific focus on direct-acting antiviral agents.

Resistance characterization of ledipasvir and velpatasvir in hepatitis C virus genotype 4

HCV genotype 4 (GT4) has often been overlooked in drug development, even though it infects ~20 million people worldwide. Ledipasvir/sofosbuvir and sofosbuvir/velpatasvir were highly efficacious in GT4 HCV-infected patients from GS-US-337-1119 and GS-US-342-1138. Here, we characterize the resistance profile of ledipasvir (LDV) and velpatasvir (VEL) in patients with GT4 HCV infection. NS5A deep-sequencing was performed for 454 patients infected with HCV GT4 at baseline, including 44 patients enrolled in GS-US-337-1119 and 116 patients enrolled in GS-US-342-1138, and at relapse for patients with virologic failure. LDV and VEL susceptibilities of 56 patient isolates were determined. In GS-US-337-1119, SVR12 rates were 100% for all subtypes except 4b and 4r. Phenotypic assessment of 56 HCV NS5A patient isolates from various GT4 subtypes indicated that LDV had high potency for the common subtypes 4a/d, and subtypes 4c/f/k/l/m/n/o/p/r/t despite the presence of resistance-associated substitutions (RASs). For the rare GT4b, LDV median EC₅₀ was higher, but with a broad range of individual values. Importantly, all GT4b isolates tested had 2-4 NS5A RASs, some including Y93H. Similarly, the 2 GT4r infected patients who had virologic relapse had rare triple RASs. Reversion of these substitutions to the consensus residue significantly increased LDV susceptibility. In GS-US-342-1138, all patients achieved SVR12, regardless of their subtype or presence of RASs. In vitro data confirmed that VEL is potent against all GT4 isolates tested. LDV and VEL are potent antiviral drugs, estimated to be effective against >95% and >99%, respectively, of GT4 HCV isolates.

American Gastroenterological Association Institute Clinical Practice Update-Expert Review: Care of Patients Who Have Achieved a Sustained Virologic Response After Antiviral Therapy for Chronic Hepatitis C Infection

Chronic hepatitis C virus infection is well-recognized as a common blood-borne infection with global public health impact affecting 3 to 5 million persons in the United States and more than 170 million persons worldwide. Chronic hepatitis C virus infection is associated with significant morbidity and mortality due to complications of liver cirrhosis and hepatocellular carcinoma. Current therapies with all-oral direct-acting antiviral agents are associated with high rates of sustained virologic response (SVR), generally exceeding 90%. SVR is associated with a reduced risk of liver cirrhosis, hepatic decompensation, need for liver transplantation, and both liver-related and all-cause mortality. However, a subset of patients who achieve SVR will remain at long-term risk for progression to cirrhosis, liver failure, hepatocellular carcinoma, and liver-related mortality. Limited evidence is available to guide clinicians on which post-SVR patients should be monitored vs discharged, how to monitor and with which tests, how frequently should monitoring occur, and for how long. In this clinical practice update, available evidence and expert opinion are used to generate best practice recommendations on the care of patients with chronic hepatitis C virus who have achieved SVR.

Second generation direct-acting antivirals - Do we expect major improvements?

The rapid progress in the development of direct-acting antiviral agents for hepatitis C has allowed the vast majority of patients to receive all oral therapy that will eliminate their virus. The success of the new regimens has led many to question the need for further developments in this field. Major improvements in drugs for hepatitis C are unlikely but we predict incremental improvements in the next few years. We hope that the next generation of drugs will address the unresolved issues for patients with genotype 3 infection where current treatments are still not entirely satisfactory and we anticipate improvements in the management of patients with renal failure. Shorter duration treatments, perhaps with novel modes of action, may allow simplified 'one-dose' treatments that will greatly expand our ability to treat patients who have difficulty accessing current services and we anticipate that the clinical community will better define the patients with advanced disease who will benefit from therapy prior to liver transplantation.

Simple Predictive Model for Identifying Patients with Chronic Hepatitis C and Hepatitis C Virus Genotype 4 Infection with a High Probability of Sustained Virologic Response with Peginterferon Alfa-2a/Ribavirin: Pooled Analysis of Data from Two Large, International Cohort Studies

INTRODUCTION

Wherever access to direct-acting antiviral agents is restricted, dual peginterferon/ribavirin (PegIFN/RBV) therapy remains an option for treatment of hepatitis C virus (HCV) genotype 4 (GT4) infection, which predominates in the Middle East and Sub-Saharan Africa. Our goal was to develop a baseline scoring system to identify GT4-infected patients with a low or high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV using data from two large cohort studies.

METHODS

Associations between baseline characteristics and SVR were explored by generalized additive models and multiple logistic regression analysis to develop a predictive model, which was then checked by bootstrapping. The score comprised four factors with points assigned thus: age ≤40, 3 points; >40 but ≤55, 2 points; alanine aminotransferase ≤1 or >3× the upper limit of normal, 1 point; no cirrhosis, 1 point; HCV RNA <50,000 IU/mL, 2 points; 50,000 to <400,000 IU/mL, 1 point. The values for a given patient are summed to produce a score from 0 to 7 where higher scores indicate higher chances of SVR.

RESULTS

Among the 459 patients, 28 (6%), 50 (11%), 92 (20%), 121 (26%), 103 (22%), and 65 (14%) patients had scores of 0-1, 2, 3, 4, 5, and 6-7, respectively, with respective SVR rates of 11%, 28%, 50%, 57%, 63%, and 83%. Relapse rates decreased with increasing prediction score (80%, 39%, 15%, 19%, 5%, and 7%, respectively). SVR rates were consistently higher in Caucasian than Black patients and in patients with a rapid virologic response HCV RNA <50 IU/mL at week 4); however, the trend toward higher SVR rates with increasing score remained apparent in each subgroup.

CONCLUSION

In conclusion, a simple scoring system can be used to identify GT4-infected patients with a high probability of achieving an SVR with PegIFN alfa-2a/RBV.

FUNDING

F. Hoffmann-La Roche Ltd.

Ledipasvir plus sofosbuvir for 12 weeks in patients with hepatitis C genotype 4 infection

Genotype 4 hepatitis C virus (HCV) was considered difficult to treat in the era of pegylated interferon-alpha (Peg-IFN-α) and ribavirin regimens. We evaluated the efficacy and safety of therapy with the nonstructural (NS) 5A inhibitor, ledipasvir, combined with the NS5B polymerase inhibitor, sofosbuvir, in patients with HCV genotype 4. In this phase 2, open-label study, 44 patients (22 treatment naïve and 22 treatment experienced) received a fixed-dose combination tablet of 90 mg of ledipasvir and 400 mg of sofosbuvir orally once-daily for 12 weeks. The primary endpoint was the percentage of patients with HCV RNA <15 IU/mL 12 weeks after stopping therapy (SVR12). Among study participants, HCV genotype 4 subtypes were well represented (4a, n = 25; 4d, n = 10; other subtypes, n = 9). Ten patients (23%) had compensated cirrhosis. Of the 22 treatment-experienced patients, 21 (95%) had a non-CC IL-28B genotype. All 44 patients completed the full 12 weeks of dosing. The SVR12 rate was 93% (41 of 44; 95% confidence interval, 81-99). SVR12 rates were similar between treatment-naïve (95%; 21 of 22) and treatment-experienced (91%; 20 of 22) patients. All 3 patients who did not achieve SVR12 had virological relapse within 4 weeks of the end of treatment; all 3 had baseline HCV RNA ≥800,000 IU/mL, a non-CC IL-28B genotype, and pretreatment NS5A resistance-associated variants. None of the patients who relapsed had cirrhosis. The most common adverse events were asthenia, headache, and fatigue. No patients experienced a serious adverse event.

CONCLUSION

The all-oral regimen of ledipasvir and sofosbuvir is an effective and safe treatment for a wide range of HCV 4 subtypes in both treatment-naïve and -experienced patients, including those with compensated cirrhosis. (EudraCT number: 2013-003978-27; Clinicaltrials.gov NCT02081079) (Hepatology 2016;64:1049-1056).

Ombitasvir, paritaprevir, and ritonavir plus ribavirin in adults with hepatitis C virus genotype 4 infection and cirrhosis (AGATE-I): a multicentre, phase 3, randomised open-label trial

BACKGROUND

Hepatitis C virus (HCV) genotype 4 infection is most commonly reported in sub-Saharan Africa and the Middle East; however, prevalence is increasing worldwide through immigration. HCV genotype 4 accounts for 20% of all infections, but clinical trial data for treatment remain limited. We assessed the combination of two direct-acting antivirals, ombitasvir (NS5A inhibitor) and paritaprevir (NS3/4A protease inhibitor; co-dosed with ritonavir) plus ribavirin in patients with HCV genotype 4 infection and compensated cirrhosis.

METHODS

In this multicentre, randomised, open-label phase 3 trial (AGATE-I), treatment-naive and interferon or pegylated interferon and ribavirin treatment-experienced patients with HCV genotype 4 infection and compensated cirrhosis were recruited from academic, public, and private hospitals in Austria, Belgium, Canada, France, Germany, Greece, Italy, and the USA. Key eligibility criteria were age 18 years or older, with chronic HCV infection assessed by the presence of anti-HCV antibodies or HCV RNA. Patients were randomly assigned (1:1) to receive 25 mg ombitasvir, 150 mg paritaprevir, and 100 mg ritonavir once daily, with weight-based ribavirin dosed twice daily for either 12 weeks or 16 weeks. Randomisation was stratified by HCV treatment history (treatment-experienced vs treatment-naive patients) and further stratified by type of non-response to previous HCV treatment (null responders, partial responders, or relapsers) for treatment-experienced patients. Treatments were assigned by an interactive response technology system with computer-generated randomisation lists prepared by personnel from the study's funding sponsor who were not involved with the conduct of the study or with data analysis. The primary outcome was the proportion of patients with a sustained virological response (HCV RNA <25 IU/mL) at post-treatment week 12 (SVR12) in the intention-to-treat population, with the lower 97·5% CI compared with a clinically relevant threshold (67%; based on SVR reported for pegylated interferon and ribavirin) to achieve superiority. The safety population included all patients who received at least one dose of study drug, and safety analyses were done by the treatment duration received (12 weeks or 16 weeks). Data presented are from the planned primary interim analysis of part one of the study when all patients enrolled in part one had reached post-treatment week 12 or prematurely discontinued from the study. This trial is registered with ClinicalTrials.gov, number NCT02265237, and part two of the trial is ongoing but closed to new participants.

FINDINGS

Between Nov 18, 2014, and May 19, 2015, we enrolled 120 eligible patients, with 59 patients assigned to receive 12 weeks of treatment and 61 patients assigned to receive 16 weeks of treatment with ombitasvir, paritaprevir, and ritonavir plus ribavirin. One patient in the 12-week group experienced virological breakthrough and one discontinued prematurely after the first day of treatment. One patient missed the post-treatment week 12 visit in the 16-week group. SVR12 was achieved in 57 (97%; 97·5% CI 86·7-99·2) of 59 patients in the 12-week group and 60 (98%; 89·6-99·8) of 61 in the 16-week group. Adverse events in more than 10% of all patients were asthenia (11 [18%] of 60 in the 12-week group; 19 [32%] of 60 in the 16-week group), fatigue (ten [17%] in the 12-week group; 20 [33%] in the 16-week group), headache (14 [23%] in the 12-week group; 14 [23%] in the 16-week group), anaemia (nine [15%] in the 12-week group; 12 [20%] in the 16-week group), pruritus (five [8%] in the 12-week group; 14 [23%] in the 16-week group), nausea (six [10%] in the 12-week group; eight [13%] in the 16-week group), and dizziness (four [7%] in the 12-week group; nine [15%] in the 16-week group).

INTERPRETATION

With SVR12 achieved in a high proportion of patients, no post-treatment relapses, and a similar adverse event profile for the 12-week and 16-week treatment groups, extending treatment with ombitasvir, paritaprevir, and ritonavir plus ribavirin beyond 12 weeks seems to have no additional benefit for patients with HCV genotype 4 infection and compensated cirrhosis and might not be necessary for this patient group.

FUNDING

AbbVie.