Efficacy and safety of elbasvir/grazoprevir in participants with hepatitis C virus genotype 1, 4, or 6 infection from the Asia-Pacific region and Russia: Final results from the randomized C-CORAL study

Cost-Effectiveness of Testing for NS5A Resistance to Optimize Treatment of Elbasvir/Grazoprevir for Chronic Hepatitis C in China

Objectives: Baseline presence of nonstructural protein 5A (NS5A) resistance-associated variants can attenuate the efficacy of new direct-acting antivirals. A potential method to attain the higher efficacy would be to screen for NS5A polymorphisms prior to the initiation of therapy and to adjust the treatment length based on the test results. However, baseline testing adds additional costs and it is unclear whether this would represent a high value strategy for chronic hepatitis C in China.

Methods: A hybrid model compared 1) standard 12-weeks treatment (no testing), 2) shortened 8-weeks treatment (no testing), and 3) baseline testing with 12-/8-weeks treatment for those with/without NS5A polymorphisms from a lifetime Chinese health care payer perspective. All model inputs were retrieved from clinical trials and publically available literature. And sensitivity analyses were also conducted to assess the impact of uncertainty.

Results: Baseline testing was associated with overall increase in total health care cost of USD 13.50 and in QALYs of 0.002 compared with standard 12-weeks treatment (no testing), yielded in an ICER of USD 6750/QALY gained. Scenario analyses suggested that shortened 8-weeks treatment (no testing) was found to be lower costs and great QALYs compared with other two strategies when the sustained virologic response (SVR) rate increased to 95%. Sensitivity analyses indicated that the results were robust.

Conclusions: Our results suggest prior assessment of NS5A sensitivity followed by optimizing treatment duration was an economic strategy. In addition, shortened 8-weeks treatment (no testing) was shown to be dominant with the SVR rate increased to 95%.

A Retrospective Cohort Study: Safety and Effectiveness of Elbasvir/Grazoprevir ± Ribavirin Compared With Ombitasvir/Paritaprevir/Ritonavir/Dasabuvir ± Ribavirin in Patients With Chronic Hepatitis C Genotype 1 Infection

Background: The direct-acting antiviral (DAA) agents are widely used to treat hepatitis C virus (HCV) genotype (GT) 1 infection, while it may cause severe liver damage. The objectives of the study were to evaluate the incidence of drug-induced liver injury (DILI), sustained virologic response at post-treatment week 12 (SVR12), and recurrence rates in HCV GT 1 infection. Methods: This was a retrospective cohort study that included patients diagnosed with HCV GT 1 infection, who had received intervention and treatment with elbasvir/grazoprevir (EBR/GZR) ± ribavirin (RBV) versus ombitasvir/paritaprevir/ritonavir (OBV/PTV/r) + dasabuvir ± RBV (as control group) for 12 or 24 weeks at a regional hospital in southern Taiwan between April 2016 and August 2018. The primary outcome of the study was to compare the incidence rate ratio (IRR) of DILI via Poisson regression, and the secondary outcome was to evaluate the effectiveness of two treatment regimens expressed as a percentage. Results: The study included 149 patients in the control group and 105 patients in the intervention group of which 99.33 and 98.1% patients, respectively, achieved SVR12. In the control group, one patient experienced relapse, whereas in the intervention group, two patients relapsed. Furthermore, in the control group, a total of nine patients developed DILI as determined during follow-up care. Of these patients, three were 55-84 years old. In the intervention group, six patients developed DILI. The IRR of DILI caused by EBR/GZR treatment was 2.84 times higher than that caused by the OBV/PTV/r treatment regimen. Conclusion: There was no significant difference between the studied DAA regimens regarding the incidence of DILI and effectiveness during the treatment. DILI occurrence during therapy did not affect the cure rate of medication. The present study results can provide reference data for drug selection among patients with HCV. Trial registration: The study was approved by DMF-CYCH (CYCH IRB No: 2018067).

Seraprevir and sofosbuvir for treatment of chronic hepatitis C virus infection: A single-arm, open-label, phase 3 trial

BACKGROUND AND AIM

This single-arm, open-label, multicenter, phase 3 trial evaluated the efficacy and safety of seraprevir, an hepatitis C virus (HCV) nonstructural protein 3/4A (NS3/4A) inhibitor, combined with sofosbuvir for treating Chinese patients with chronic HCV infection without cirrhosis.

METHODS

Treatment-naive or interferon-experienced adult patients without cirrhosis were treated with a universal, combinational regimen of seraprevir 100 mg, twice daily and sofosbuvir 400 mg, once daily, for 12 or 24 weeks. The primary efficacy endpoint was sustained virologic response at week 12 after treatment (SVR12).

RESULTS

Overall, 205 patients with genotype 1 HCV infection without cirrhosis were enrolled from 23 sites, 202 of whom completed the full treatment and post-treatment course and 3 discontinued follow-up. In total, 27 patients (13.2%) were interferon experienced. SVR12 was achieved by 201 out of 205 (98.0% [95% CI, 95.1%, 99.5%]) patients, 100.0% of patients with genotype 1a, and 98.0% of genotype 1b. In the other exploratory study, SVR 12 was achieved by 100% patients with genotype 2 (n = 21), genotype 3 (n = 7), and genotype 6 (n = 8). The majority of adverse events were mild to moderate and transient and did not require a specific medical intervention.

CONCLUSIONS

The all-oral, ribavirin-free regimen of seraprevir and sofosbuvir is an effective and well-tolerated treatment option for Chinese patients mono-infected with HCV, including those with a history of interferon treatment.

Safety and tolerability of elbasvir/grazoprevir in chronic hepatitis C virus therapy: Integrated analysis from clinical trials

Direct-acting antiviral treatments for chronic hepatitis C virus (HCV) infection are generally safe; however, understanding the safety profile of each regimen is essential for their continued use. Safety data were pooled from 12 clinical trials of elbasvir/grazoprevir (EBR/GZR) that enrolled adult participants with HCV infection. Pooled analyses are presented for participants receiving EBR/GZR for 12 weeks and those receiving EBR/GZR plus ribavirin (RBV) for 16-18 weeks. Safety data are also presented for participants with comorbidities receiving EBR/GZR for 12 weeks in individual clinical trials (chronic kidney disease [CKD] stage 4/5, inherited blood disorders [IBLD] or receiving opioid agonist therapy [OAT]). Among 1743 participants receiving EBR/GZR for 12 weeks, 1068 (61.3%) reported ≥1 adverse event (AE) and 491 had AEs (28.2%) considered drug-related. The most frequent AEs were headache (10.6%), fatigue (8.7%), nasopharyngitis (5.8%), nausea (5.1%) and diarrhoea (5.0%). Serious AEs were reported by 37 participants (2.1%), and 12 (0.7%) discontinued treatment due to an AE. In populations with CKD 4/5 or IBLD or receiving OAT, safety was similar in participants receiving EBR/GZR for 12 weeks and those receiving placebo. Some AEs occurred at higher frequencies in participants receiving RBV compared with those receiving EBR/GZR alone: fatigue (32.7% vs 8.7%); headache (21.6% vs 10.6%); and nausea (15.8% vs 5.1%). Safety was similar in participants with and those without cirrhosis. Grade 3/4 alanine aminotransferase elevations were reported in 0.7% participants. EBR/GZR is a safe treatment option for individuals with HCV genotype (GT) 1 or GT4 infections, even those with challenging comorbidities such as CKD or IBLD and those receiving OAT.

Efficacy and Safety of All-oral Emitasvir and Sofosbuvir in Patients with Genotype 1b HCV Infections without Cirrhosis

Background and Aims: Emitasvir is a new type of hepatitis C virus (HCV) nonstructural protein 5A (NS5A) inhibitor, and the data of phase 2 trial has shown emitasvir-sofosbuvir to have good safety and tolerance. We conducted this phase 3 trial to further verify the efficacy and safety. Methods: We evaluated the antiviral activity and safety of a 12-week regimen of emitasvir phosphate (100 mg) combined with sofosbuvir (400 mg) once daily in non-cirrhotic patients with genotype 1 HCV infection. The primary endpoint was a sustained virological response at 12 weeks (SVR12) after the end of treatment. Results: Of the 362 patients enrolled in the trial, 39.8% were male, 99.2% had HCV genotype 1b, 0.8% had genotype 1a and 79.8% were treatment-naïve. The average age was 47.2 years. All patients completed the treatment and follow-up. All 3 patients with genotype 1a achieved SVR. Two genotype 1b treatment-naïve patients experienced virologic relapse. The rate of SVR12 was 99.7% (358/359), and SVR24 was 99.4% (357/359) in genotype 1b. Overall, 36.2% had resistance-associated substitutions (RASs) in NS5A and 98.3% had RASs in NS5B at baseline. The RASs at baseline had no effect on the rates of response. Serious adverse events were reported in 16 patients and were not related to emitasvir-sofosbuvir. Most adverse events did not require therapy. Conclusions: The 12 weeks of treatment with emitasvir-sofosbuvir was a highly efficient and safe treatment for a wide range of patients with HCV genotype 1b infection without cirrhosis, who had not been treated or who had been treated with interferon-based regimen previously.

Real-world experience with Grazoprevir/Elbasvir in the treatment of previously "difficult to treat" patients infected with hepatitis C virus genotype 1 and 4

BACKGROUND AND AIM

Grazoprevir/elbasvir (GZR/EBR) was approved for the treatment of chronic hepatitis C virus (HCV) genotype 1 and 4 infected patients with or without compensated liver cirrhosis. The aim of this study was to assess GZR/EBR regimen in the real-world experience, particularly in previously "difficult-to-treat" patients with chronic kidney diseases, human immunodeficiency virus-coinfected, cirrhotics, and treatment-experienced.

METHODS

The analysis included patients treated with GZR/EBR selected from 10 152 individuals from the EpiTer-2 database, large national real-world study evaluating antiviral treatment in 22 Polish hepatology centers between 2015 and 2018. Data were completed retrospectively and submitted online.

RESULTS

A total of 1615 patients who started GZR/EBR therapy in 2017 and 2018 with a female predominance (54%) and median age of 54 years were analyzed. The majority were infected with GT1b (89%) and treatment naïve (81%). Liver cirrhosis was diagnosed in 19%, and 70% of patients had comorbidities, of which chronic renal disease was present in 7% and HIV-coinfection in 4%. Overall, a sustained virologic response (SVR) was achieved by 95% according to intent-to-treat (ITT) and 98% after exclusion of lost to follow up (modified ITT). No differences were found in cure rate between all included patients and subpopulations previously considered as difficult-to-treat. Majority of patients completed the treatment course as scheduled, adverse events were mostly mild and did not lead to therapy discontinuation.

CONCLUSIONS

GZR/EBR treatment carried-out in patients infected with HCV genotype 1 and 4 demonstrated good tolerability and an excellent SVR rate with no effectiveness reduction in so called difficult-to-treat populations.

Elbasvir/grazoprevir for hepatitis C virus genotype 1b East-Asian patients receiving hemodialysis

Data regarding the efficacy and tolerability of elbasvir/grazoprevir (EBR/GZR) for East-Asian hepatitis C virus genotype 1b (HCV GT1b) patients receiving hemodialysis were limited. We prospectively recruited 40 HCV GT1b hemodialysis patients who received EBR/GZR for 12 weeks at 6 academic centers in Taiwan. The efficacy endpoints were sustained virologic response 12 weeks off-therapy (SVR₁₂) by intention-to-treat (ITT) modified ITT (mITT) analyses. Patients’ baseline characteristics, early viral kinetics and HCV resistance-associated substitutions (RASs) at HCV non-structural 3 and 5 A (NS3 and NS5A) regions potentially affecting SVR₁₂ were analyzed. The tolerability for EBR/GZR was also assessed. The SVR₁₂ rates by ITT and mITT analyses were 95% (38 of 40 patients; 95% confidence interval (CI): 83.5–98.6%) and 100% (38 of 38 patients; 95% CI: 90.8–100%), respectively. Patients’ baseline characteristics, on-treatment viral decline, and baseline HCV RASs did not affect SVR₁₂. All patients tolerated treatment well. Among 5 patients who had serious adverse events (AEs) including one death due to on-treatment suicide and the other death due to off-therapy acute myocardial infarction, none of these events were judged related to EBR/GZR. The common AEs included upper respiratory tract infection (7.5%), fatigue (5.0%) and anorexia (5.0%). Nine (22.5%) and 8 (20.0%) patients had on-treatment hemoglobin levels of 9.0–10.0 g/dL and 7.0–9.0 g/dL. Three (7.5%) patients had on-treatment elevated alanine aminotransferase (ALT) quotient > 2.5, in whom one (2.5%) had EBR/GZR-induced late ALT elevation. No patients developed hyperbilirubinemia or hepatic decompensation. In conclusion, treatment with EBR/GZR is effective and well-tolerated for East-Asian HCV GT1b patients receiving hemodialysis.

Hepatitis C genotype 4: A report on resistance-associated substitutions in NS3, NS5A, and NS5B genes

AUTHOR CONTRIBUTION

FN performed the literature review and wrote the manuscript; STZ coauthored, edited, and reviewed the manuscript.

ABSTRACT

Treatment response in Hepatitis C virus (HCV) has generated varied effects in patients. Recently, nonresponsive and relapse patients related to host and genotype variabilities have been reported in clinical trials. However, these trials included minimal sample sizes of patients with genotype 4, the most prevalent genotype in Egypt and the Middle East, compared with genotypes 1 and 2. The genetic variabilities that have been detected within the HCV genes, especially the ones associated with genotype 4, and are linked to treatment response, will be the focus of this review with emphasis on direct acting antiviral agents. In addition, the major studies and clinical trials performed globally and their inclusivity of genotype 4 are reported. This review also delineates future study areas and missing data that need further investigation when it comes to genotype 4.

Elbasvir/Grazoprevir for HCV Infection in Russia: A Randomized Trial

Purpose

Hepatitis C virus (HCV) infection is a major healthcare concern in Russia, where almost 5 million individuals are viremic. Elbasvir/grazoprevir is a fixed-dose combination therapy for the treatment of HCV genotype 1 and genotype 4 infection. The present analysis aimed to assess the safety and efficacy of elbasvir/grazoprevir in individuals with HCV infection enrolled at Russian study sites in the C-CORAL study.

Patients and Methods

C-CORAL (Protocol PN-5172-067; NCT02251990) was a Phase 3, placebo-controlled, double-blind study conducted throughout Asia and Russia. Treatment-naive participants with chronic HCV infection were randomly assigned to receive immediate or deferred treatment with elbasvir 50 mg/grazoprevir 100 mg once daily for 12 weeks. Participants in the immediate-treatment group received elbasvir/grazoprevir for 12 weeks, and those in the deferred-treatment group received placebo for 12 weeks, followed by open-label elbasvir/grazoprevir for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after completion of therapy (SVR12).

Results

One hundred and nineteen Russian participants were randomized (immediate-treatment group, n=88; deferred-treatment group, n=31). Most participants were white (99%) with HCV genotype 1b infection (97%) and mild-to-moderate (F0–F2) fibrosis (70%). SVR12 was achieved by 98.9% participants in the immediate-treatment group and by 100% of those receiving deferred elbasvir/grazoprevir in the deferred-treatment group. One participant relapsed with nonstructural protein 5A (NS5A) L28M and Y93H resistance-associated substitutions at baseline and at time of failure. Drug-related adverse events were reported by 19% of participants receiving elbasvir/grazoprevir in the immediate-treatment group and by 16% of those receiving placebo in the deferred-treatment group. No serious adverse event or deaths occurred, and no participant discontinued treatment owing to an adverse event.

Conclusion

Elbasvir/grazoprevir for 12 weeks was highly effective in treatment-naive Russian individuals with HCV genotype 1b infection.

Viral Hepatitis C Therapy: Pharmacokinetic and Pharmacodynamic Considerations: A 2019 Update

It has been estimated by the World Health Organization (WHO) that over 71 million people were infected with the hepatitis C virus (HCV) in 2015. Since then, a number of highly effective direct-acting antiviral (DAA) regimens have been licensed for the treatment of chronic HCV infection: sofosbuvir/daclatasvir, sofosbuvir/ledipasvir, elbasvir/grazoprevir, sofosbuvir/velpatasvir, glecaprevir/pibrentasvir, and sofosbuvir/velpatasvir/voxilaprevir. With these treatment regimens, almost all chronic HCV-infected patients, even including prior DAA failures, can be treated effectively and safely. It is therefore likely that further development of DAAs will be limited. In this descriptive review we provide an overview of the clinical pharmacokinetic characteristics of currently available DAAs by describing their absorption, distribution, metabolism, and excretion. Potential drug-drug interactions with the DAAs are briefly discussed. Furthermore, we summarize what is known about the pharmacodynamics of the DAAs in terms of efficacy and safety. We briefly discuss the relationship between the pharmacokinetics of the DAAs and efficacy or toxicity in special populations, such as hard to cure patients and patients with liver cirrhosis, liver transplantation, renal impairment, hepatitis B virus or HIV co-infection, bleeding disorders, and children. The aim of this overview is to educate/update prescribers and pharmacists so that they are able to safely and effectively treat HCV-infected patients even in the presence of underlying co-infections or co-morbidities.

An integrated analysis of elbasvir/grazoprevir in Korean patients with hepatitis C virus genotype 1b infection

BACKGROUND/AIMS

In the Republic of Korea, an estimated 231,000 individuals have chronic hepatitis C virus (HCV) infection. The aim of the present analysis was to evaluate the safety and efficacy of elbasvir/grazoprevir (EBR/GZR) administered for 12 weeks in Korean patients who were enrolled in international clinical trial phase 3 studies.

METHODS

This was a retrospective, integrated analysis of data from patients with HCV genotype (GT) 1b infection enrolled at Korean study sites in four EBR/GZR phase 3 clinical trials. Patients were treatment-naive or had previously failed interferon-based HCV therapy, and included those with human immunodeficiency virus coinfection or ChildPugh class A cirrhosis. All patients received EBR 50 mg/GZR 100 mg once daily for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after completion of therapy (SVR12, HCV RNA <15 IU/mL).

RESULTS

SVR12 was achieved by 73 of 74 (98.6%) patients. No patients had virologic failure and one discontinued from the study after withdrawing consent. SVR12 rates were uniformly high across all patient subgroups. A total of 16 patients had nonstructural protein 5A resistance-associated substitutions at baseline (16/73, 22%), all of whom achieved SVR12. Adverse events (AEs) reported in >5% of patients were fatigue (6.8%), upper respiratory tract infection (5.4%), headache (5.4%), and nausea (5.4%). Thirteen patients (17.6%) reported drug-related AEs, two serious AEs occurred, and two patients discontinued treatment owing to an AEs.

CONCLUSION

In this retrospective analysis, EBR/GZR administered for 12 weeks was well-tolerated and highly effective in Korean patients with HCV GT1b infection.

Hepatitis C virus cure with direct acting antivirals: Clinical, economic, societal and patient value for China

About 10 million people in China are infected with hepatitis C virus (HCV), with the seroprevalence of anti-HCV in the general population estimated at 0.6%. Delaying effective treatment of chronic hepatitis C (CHC) is associated with liver disease progression, cirrhosis, hepatocellular carcinoma, and liver-related mortality. The extrahepatic manifestations of CHC further add to the disease burden of patients. Managing CHC-related advanced liver diseases and systemic manifestations are costly for both the healthcare system and society. Loss of work productivity due to reduced well-being and quality of life in CHC patients further compounds the economic burden of the disease. Traditionally, pegylated-interferon plus ribavirin (PR) was the standard of care. However, a substantial number of patients are ineligible for PR treatment, and only 40%-75% achieved sustained virologic response. Furthermore, PR is associated with impairment of patient-reported outcomes (PROs), high rates of adverse events, and poor adherence. With the advent of direct acting antivirals (DAAs), the treatment of CHC patients has been revolutionized. DAAs have broader eligible patient populations, higher efficacy, better PRO profiles, fewer adverse events, and better adherence rates, thereby making it possible to cure a large proportion of all CHC patients. This article aims to provide a comprehensive evaluation on the value of effective, curative hepatitis C treatment from the clinical, economic, societal, and patient experience perspectives, with a focus on recent data from China, supplemented with other Asian and international experiences where China data are not available.