Efficacy of Glecaprevir and Pibrentasvir in Patients With Genotype 1 Hepatitis C Virus Infection With Treatment Failure After NS5A Inhibitor Plus Sofosbuvir Therapy

SASLT guidelines: Update in treatment of hepatitis C virus infection, 2024

ABSTRACT

Hepatitis C virus (HCV) infection has been a major global health concern, with a significant impact on public health. In recent years, there have been remarkable advancements in our understanding of HCV and the development of novel therapeutic agents. The Saudi Society for the Study of Liver Disease and Transplantation formed a working group to develop HCV practice guidelines in Saudi Arabia. The methodology used to create these guidelines involved a comprehensive review of available evidence, local data, and major international practice guidelines regarding HCV management. This updated guideline encompasses critical aspects of HCV care, including screening and diagnosis, assessing the severity of liver disease, and treatment strategies. The aim of this updated guideline is to assist healthcare providers in the management of HCV in Saudi Arabia. It summarizes the latest local studies on HCV epidemiology, significant changes in virus prevalence, and the importance of universal screening, particularly among high-risk populations. Moreover, it discusses the promising potential for HCV elimination as a public health threat by 2030, driven by effective treatment and comprehensive prevention strategies. This guideline also highlights evolving recommendations for advancing disease management, including the treatment of HCV patients with decompensated cirrhosis, treatment of those who have previously failed treatment with the newer medications, management in the context of liver transplantation and hepatocellular carcinoma, and treatment for special populations.

Glecaprevir-pibrentasvir for 4 weeks among people with recent HCV infection: The TARGET3D study

Background & Aims

Short duration treatment may aid HCV elimination among key populations. This study evaluated the efficacy of glecaprevir-pibrentasvir for 4 weeks among people with recent HCV infection.

Methods

In this single-arm multicentre international trial, adults with recent HCV (duration of infection <12 months) received glecaprevir-pibrentasvir 300 mg-120 mg daily for 4 weeks. Primary infection was defined as a first positive anti-HCV antibody and/or HCV RNA measurement within 6 months of enrolment and either acute clinical hepatitis within 12 months (symptomatic illness or alanine aminotransferase >10x the upper limit of normal) or antibody seroconversion within 18 months. Reinfection was defined as new positive HCV RNA within 6 months and prior clearance (spontaneous or treatment). The primary endpoint was sustained virological response at 12 weeks post-treatment (SVR12) in the intention-to-treat (ITT) and per-protocol (PP) populations.

Results

Twenty-three participants (96% men, 70% HIV, 57% ever injected drugs) received treatment, of whom 74% had genotype 1a infection and 35% recent reinfection. At baseline, median duration of infection was 17 weeks (IQR 11-29) and HCV RNA was 5.8 log10IU/ml (IQR 5.2-6.9). SVR12 was achieved by 78% (18/23; 95% CI 56-93%) and 82% (18/22; 95% CI 60-95%) of the ITT and PP populations, respectively, and in 100% (12/12; 95% CI 74-100%) of participants with baseline HCV RNA ≤6 log10. There were four cases of virological failure (relapse); three received retreatment with 12 weeks sofosbuvir-velpatasvir or grazoprevir-elbasvir (SVR, n = 2; loss to follow-up, n = 1). No serious adverse events were reported.

Conclusion

While most achieved SVR, the efficacy of a 4-week regimen of glecaprevir-pibrentasvir was lower than observed with longer treatment durations (≥6 weeks) among people with recent HCV.

Trial Registration

Clinicaltrials.gov Identifier: NCT02634008.

Impact and implications

Short duration treatment may aid HCV elimination among key populations. This investigator-initiated single-arm multicentre international pilot trial demonstrated that efficacy of glecaprevir-pibrentasvir for 4 weeks among people with recent HCV infection was sub-optimal (SVR12 78% ITT, 82% PP). Baseline HCV RNA appeared to impact response, with higher efficacy among participants with lower baseline HCV RNA (≤6 log10; SVR12 100% ITT, 12/12). While most achieved SVR, the efficacy of 4 weeks of glecaprevir-pibrentasvir was below that seen with longer treatment durations (≥6 weeks).

Hepatitis C

Hepatitis C virus (HCV) is a hepatotropic RNA virus that can cause acute and chronic hepatitis, with progressive liver damage resulting in cirrhosis, decompensated liver disease, and hepatocellular carcinoma. In 2016, WHO called for the elimination of HCV infection as a public health threat by 2030. Despite some progress, an estimated 57 million people were living with HCV infection in 2020, and 300 000 HCV-related deaths occur per year. The development of direct-acting antiviral therapy has revolutionised clinical care and generated impetus for elimination, but simplified and broadened HCV screening, enhanced linkage to care, and higher coverage of treatment and primary prevention strategies are urgently required.

Direct-Acting Antiviral Therapy for Treatment of Acute and Recent Hepatitis C Virus Infection: A Narrative Review

Following the discovery of hepatitis C virus (HCV) in 1989, 3 decades of basic, translational, and clinical research culminated in the development of direct-acting antiviral (DAA) therapy-curative oral treatment for HCV infection. The availability of DAA therapy revolutionized HCV clinical management, including acute (duration of infection <6 mo) and recent (duration of infection <12 mo) infection. Several DAA regimens, including the contemporary pan-genotypic combinations of sofosbuvir-velpatasvir and glecaprevir-pibrentasvir, have been shown to be safe and effective among people with acute and recent HCV infection, highlighting their potential in an HCV controlled human infection model. This article describes the natural history and management of acute and recent HCV infection in the era of DAA therapy and outlines a strategy for use of DAA therapies in the setting of an HCV controlled human infection model.

Hepatitis C Guidance 2023 Update: AASLD-IDSA Recommendations for Testing, Managing, and Treating Hepatitis C Virus Infection

The Infectious Diseases Society of America and the American Association for the Study of Liver Diseases have collaboratively developed evidence-based guidance regarding the diagnosis, management, and treatment of hepatitis C virus (HCV) infection since 2013. A panel of clinicians and investigators with extensive infectious diseases or hepatology expertise specific to HCV infection periodically review evidence from the field and update existing recommendations or introduce new recommendations as evidence warrants. This update focuses on changes to the guidance since the previous 2020 published update, including ongoing emphasis on recommended universal screening; management recommendations for incomplete treatment adherence; expanded eligibility for simplified chronic HCV infection treatment in adults with minimal monitoring; updated treatment and retreatment recommendations for children as young as 3 years old; management and treatment recommendations in the transplantation setting; and screening, treatment, and management recommendations for unique and key populations.

Newly diagnosed hepatitis C infection after pancreas transplantation with multiple treatment failures

This case represents the first report of a detected hepatitis C virus (HCV) infection following a pancreas transplantation that failed two different sofosbuvir (SOF)-based treatments. We present the case of a woman in her 30s with a history of kidney transplantation, who developed viremic symptoms 3 months after pancreas transplantation and with two subsequent negative HCV antibody tests. Further work-up revealed a positive HCV RNA test (genotype 1A, treatment naive). Two different direct-acting antiviral agents regimes with SOF failed in our case, and the patient achieved a sustained virological response with a 16-week course of glecaprevir/pibrentasvir.

Rescue Therapy after Failure of HCV Antiviral Treatment with Interferon-Free Regimens

Direct-acting antivirals (DAA) regimens have provided hope for eliminating hepatitis C virus (HCV) infection. Patients following ineffective therapy with DAA, especially those previously treated with inhibitors of non-structural protein 5A (NS5A), remain a challenge. The study aimed to assess the effectiveness of DAA pangenotypic options in patients after failure of NS5A containing genotype-specific regimens. The analysis included 120 patients selected from the EpiTer-2 database with data on 15675 HCV-infected individuals treated with IFN-free therapies from 1 July 2015 to 30 June 2022 at 22 Polish hepatology centres. The majority of them were infected with genotype (GT) 1b (85.8%) and one-third was diagnosed with fibrosis F4. Among the rescue pangenotypic regimens, the most commonly used was the sofosbuvir/velpatasvir (SOF/VEL) ± ribavirin (RBV) combination. The sustained virologic response, which was a measure of treatment effectiveness, was achieved by 102 patients, resulting in cure rate of 90.3% in the per protocol analysis. All 11 non-responders were infected with GT1b, 7 were diagnosed with cirrhosis, and 9 were treated with SOF/VEL±RBV. We demonstrated the high effectiveness of the pangenotypic rescue options in patients after genotype specific NS5A-containing regimens failures, identifying cirrhosis as a negative prognostic factor of treatment effectiveness.

Evaluation of machine learning algorithms for predicting direct-acting antiviral treatment failure among patients with chronic hepatitis C infection

Despite the availability of efficacious direct-acting antiviral (DAA) therapy, the number of people infected with hepatitis C virus (HCV) continues to rise, and HCV remains a leading cause of liver-related morbidity, liver transplantation, and mortality. We developed and validated machine learning (ML) algorithms to predict DAA treatment failure. Using the HCV-TARGET registry of adults who initiated all-oral DAA treatment, we developed elastic net (EN), random forest (RF), gradient boosting machine (GBM), and feedforward neural network (FNN) ML algorithms. Model performances were compared with multivariable logistic regression (MLR) by assessing C statistics and other prediction evaluation metrics. Among 6525 HCV-infected adults, 308 patients (4.7%) experienced DAA treatment failure. ML models performed similarly in predicting DAA treatment failure (C statistic [95% CI]: EN, 0.74 [0.69-0.79]; RF, 0.74 [0.69-0.80]; GBM, 0.72 [0.67-0.78]; FNN, 0.75 [0.70-0.80]), and all 4 outperformed MLR (C statistic [95% CI]: 0.51 [0.46-0.57]), and EN used the fewest predictors (n = 27). With Youden index, the EN had 58.4% sensitivity and 77.8% specificity, and nine patients were needed to evaluate to identify 1 DAA treatment failure. Over 60% treatment failure were classified in top three risk decile subgroups. EN-identified predictors included male sex, treatment < 8 weeks, treatment discontinuation due to adverse events, albumin level < 3.5 g/dL, total bilirubin level > 1.2 g/dL, advanced liver disease, and use of tobacco, alcohol, or vitamins. Addressing modifiable factors of DAA treatment failure may reduce the burden of retreatment. Machine learning algorithms have the potential to inform public health policies regarding curative treatment of HCV.

Machine learning algorithms for predicting direct-acting antiviral treatment failure in chronic hepatitis C: An HCV-TARGET analysis

BACKGROUND AND AIMS

We aimed to develop and validate machine learning algorithms to predict direct-acting antiviral (DAA) treatment failure among patients with HCV infection.

APPROACH AND RESULTS

We used HCV-TARGET registry data to identify HCV-infected adults receiving all-oral DAA treatment and having virologic outcome. Potential pretreatment predictors (n = 179) included sociodemographic, clinical characteristics, and virologic data. We applied multivariable logistic regression as well as elastic net, random forest, gradient boosting machine (GBM), and feedforward neural network machine learning algorithms to predict DAA treatment failure. Training (n = 4894) and validation (n = 1631) patient samples had similar sociodemographic and clinical characteristics (mean age, 57 years; 60% male; 66% White; 36% with cirrhosis). Of 6525 HCV-infected adults, 95.3% achieved sustained virologic response, whereas 4.7% experienced DAA treatment failure. In the validation sample, machine learning approaches performed similarly in predicting DAA treatment failure (C statistic [95% CI]: GBM, 0.69 [0.64-0.74]; random forest, 0.68 [0.63-0.73]; feedforward neural network, 0.66 [0.60-0.71]; elastic net, 0.64 [0.59-0.70]), and all four outperformed multivariable logistic regression (0.51 [0.46-0.57]). Using the Youden index to identify the balanced risk score threshold, GBM had 66.2% sensitivity and 65.1% specificity, and 12 individuals were needed to evaluate to identify 1 DAA treatment failure. Over 55% of patients with treatment failure were classified by the GBM in the top three risk decile subgroups (positive predictive value: 6%-14%). The top 10 GBM-identified predictors included albumin, liver enzymes (aspartate aminotransferase, alkaline phosphatase), total bilirubin levels, sex, HCV viral loads, sodium level, HCC, platelet levels, and tobacco use.

CONCLUSIONS

Machine learning algorithms performed effectively for risk prediction and stratification of DAA treatment failure.

HCV genome-wide analysis for development of efficient culture systems and unravelling of antiviral resistance in genotype 4

OBJECTIVE

HCV-genotype 4 infections are a major cause of liver diseases in the Middle East/Africa with certain subtypes associated with increased risk of direct-acting antiviral (DAA) treatment failures. We aimed at developing infectious genotype 4 cell culture systems to understand the evolutionary genetic landscapes of antiviral resistance, which can help preserve the future efficacy of DAA-based therapy.

DESIGN

HCV recombinants were tested in liver-derived cells. Long-term coculture with DAAs served to induce antiviral-resistance phenotypes. Next-generation sequencing (NGS) of the entire HCV-coding sequence identified mutation networks. Resistance-associated substitutions (RAS) were studied using reverse-genetics.

RESULT

The in-vivo infectious ED43(4a) clone was adapted in Huh7.5 cells, using substitutions identified in ED43(Core-NS5A)/JFH1-chimeric viruses combined with selected NS5B-changes. NGS, and linkage analysis, permitted identification of multiple genetic branches emerging during culture adaptation, one of which had 31 substitutions leading to robust replication/propagation. Treatment of culture-adapted ED43 with nine clinically relevant protease-DAA, NS5A-DAA and NS5B-DAA led to complex dynamics of drug-target-specific RAS with coselection of genome-wide substitutions. Approved DAA combinations were efficient against the original virus, but not against variants with RAS in corresponding drug targets. However, retreatment with glecaprevir/pibrentasvir remained efficient against NS5A inhibitor and sofosbuvir resistant variants. Recombinants with specific RAS at NS3-156, NS5A-28, 30, 31 and 93 and NS5B-282 were viable, but NS3-A156M and NS5A-L30Δ (deletion) led to attenuated phenotypes.

CONCLUSION

Rapidly emerging complex evolutionary landscapes of mutations define the persistence of HCV-RASs conferring resistance levels leading to treatment failure in genotype 4. The high barrier to resistance of glecaprevir/pibrentasvir could prevent persistence and propagation of antiviral resistance.

Linkage of resistance-associated substitutions in GT1 sofosbuvir + NS5A inhibitor failures treated with glecaprevir/pibrentasvir

BACKGROUND & AIMS

Retreatment with glecaprevir/pibrentasvir (G/P) resulted in a rate of sustained virologic response 12 weeks after treatment completion (SVR12) of >90% in HCV genotype 1 (GT1) patients who previously failed a regimen of sofosbuvir plus an NS5A inhibitor (NS5Ai). This study investigated the prevalence and impact of baseline NS3 and NS5A resistance-associated substitutions (RASs) on the efficacy of G/P in prior GT1 sofosbuvir+NS5Ai failures and the persistence of treatment-emergent RASs.

METHODS

Longitudinal samples from 177 patients enrolled in a phase IIIb, randomized pragmatic clinical trial were analyzed. Patients without cirrhosis were randomized to 12 or 16 weeks of G/P, and patients with compensated cirrhosis were randomized to G/P and ribavirin for 12 weeks or G/P for 16 weeks. Linkage of RAS was identified using Primer-ID next-generation sequencing at a 15% cut-off.

RESULTS

Of 177 patients, 169 (95.5%) were PI-naïve. All 33 GT1b-infected patients achieved SVR12. In GT1a-infected patients, baseline NS5A RASs were prevalent (74.5%, 105/141) but NS3 RASs were uncommon. Baseline NS3 RASs had no impact on G/P efficacy and patients with baseline NS5A RASs showed a numerically but not statistically significantly lower SVR12 rate compared to those without NS5A RASs (89% vs. 97%). SVR12 was achieved in 34 of 35 (97%) patients without NS5A baseline substitution, and 53 of 57 (93%), 35 of 40 (88%), 5 of 8 (63%) with single, double-linked, and triple-linked NS5A substitutions, respectively. Among 13 patients with virologic failure, 4 acquired treatment-emergent NS3 RASs and 10 acquired NS5A RASs.

CONCLUSION

Baseline NS5A RASs were highly prevalent. The presence of an increasing number of linked NS5A RASs in GT1a showed a trend in decreasing SVR12 rates, although no specific NS5A RASs or their linkage pattern were associated with lower SVR12 rates.

LAY SUMMARY

Direct-acting antivirals have revolutionized the treatment of chronic hepatitis C infection, but treatment failure occurs in some patients. Retreatment of patients who previously failed a regimen consisting of sofosbuvir and an NS5A inhibitor with a regimen of glecaprevir and pibrentasvir (G/P) is >90% effective. Herein, we analyzed samples from these patients and showed that retreatment efficacy with G/P is lower in patients with double- or triple-linked NS5A resistance mutations than in patients with single or no NS5A resistance mutations.

CLINICAL TRIAL NUMBER

NCT03092375.

Hepatitis C virus treatment failure: Clinical utility for testing resistance-associated substitutions

The hepatitis C virus has a high mutation capacity that leads to the emergence of resistance-associated substitutions (RAS). However, the consequence of resistance selection during new direct-acting antiviral drug (DAA) treatment is not necessarily the therapeutic failure. In fact, DAA treatment has shown a high rate (> 95%) of sustained virological response even when high baseline RAS prevalence has been reported. In the context of RAS emergence and high rates of sustained viral response, the clinical relevance of variants harboring RAS is still controversial. Therefore, in order to summarize the data available in international guidelines, we have reviewed the clinical utility of testing RAS in the era of new pangenotypic DAA drugs.

World-wide Prevalence of Substitutions in HCV Genome Associated With Resistance to Direct-Acting Antiviral Agents

BACKGROUND & AIMS

The efficacy of direct-acting antiviral agents against hepatitis C virus (HCV) infection can be compromised by substitutions in the HCV genome that occur before treatment (resistance-associated substitutions [RASs]). We performed a meta-analysis to determine the prevalence of RASs and their effects.

METHODS

We searched publication databases for studies of HCV RNA substitutions that mediate resistance to direct-acting antiviral agents. Findings from 50 studies of the prevalence of RAS in HCV, from 32 countries, were used in a meta-analysis. We retrieved the HCV RNA sequence from the Los Alamos HCV sequence database to estimate the prevalence of the RASs. The degree of resistance to treatment conferred by each RAS was determined based on fold-change in the 50% effective concentration of the drugs.

RESULTS

Our final analysis included data from 49,744 patients with HCV infection and 12,612 HCV sequences. We estimated the prevalence of 56 RASs that encoded amino acids and 114 specific RASs. The average prevalence of RASs was highest in HCV genotype (GT) 6, followed by HCV GT1a, GT2, GT1b, GT3, and GT4. The highest prevalence of RASs observed encoded Q80K in NS3 to NS4A of HCV GT1a, Y93T in NS5A of GT1a, and C316N in NS5B of GT1b. The greatest number of RASs were observed at D168 in NS3 to NS4A, at Y93 in NS5A, and at C316 in NS5B. The prevalence of RASs and mutation burdens were high in Japan, the United States, Germany, Thailand, and the United Kingdom; low in Russia, Brazil, Egypt, and India; and intermediate in China, Canada, Australia, Spain, and France.

CONCLUSIONS

In a meta-analysis, we found evidence for 114 RASs in HCV of different genotypes. Patients with HCV infection should be tested for RASs before treatment is selected, especially in regions with a high prevalence of RASs.

Progress and challenges in the comprehensive management of chronic viral hepatitis: Key ways to achieve the elimination

Chronic viral hepatitis is a significant health problem throughout the world, which already represents high annual mortality. By 2040, chronic viral hepatitis due to virus B and virus C and their complications cirrhosis and hepatocellular carcinoma will be more deadly than malaria, vitellogenesis-inhibiting hormone, and tuberculosis altogether. In this review, we analyze the global impact of chronic viral hepatitis with a focus on the most vulnerable groups, the goals set by the World Health Organization for the year 2030, and the key points to achieve them, such as timely access to antiviral treatment of direct-acting antiviral, which represents the key to achieving hepatitis C virus elimination. Likewise, we review the strategies to prevent transmission and achieve control of hepatitis B virus. Finally, we address the impact that the coronavirus disease 2019 pandemic has had on implementing elimination strategies and the advantages of implementing telemedicine programs.

Treatment failure with DAA therapy: Importance of resistance

Viral resistance is a major reason for virological failure in patients being treated with direct-acting antivirals (DAAs) for chronic HCV infection. However, the importance of viral resistance mainly depends on the DAA regimen and HCV genotype. For first-line therapy with glecaprevir/pibrentasvir (G/P) or velpatasvir/sofosbuvir (VEL/SOF) no general baseline resistance analysis is required because of the high antiviral activity and high barrier to resistance. If available, resistance testing may help to optimise therapy in certain subgroups of patients with HCV genotype 3 and other rare HCV geno/subtypes. Voxilaprevir/velpatasvir/sofosbuvir (VOX/VEL/SOF) is the first choice for the second-line treatment of patients following a previous DAA failure, with rates of viral eradication above 90% irrespective of the presence of resistance-associated substitutions (RASs). However, in resource-limited settings, only first-generation DAAs may be available for second-line therapy. Here, RASs selected during initial antiviral therapy should be considered if testing is available and rescue treatment should include a switch to a regimen with a new DAA class to optimise treatment response. Patients with HCV genotype 3 are overrepresented in the group who experience DAA treatment failure. Limited data are available for third-line therapies, but promising results have been achieved with G/P plus SOF or VOX/VEL/SOF with or without ribavirin for 12 to 24 weeks; these regimens should be administered irrespective of a patient's RAS profile.

Efficacy and Safety of Glecaprevir/Pibrentasvir in Patients with Chronic HCV Infection

Hepatitis C virus (HCV) infection is a major cause of end-stage liver disease, including decompensated cirrhosis and hepatocellular carcinoma. Over 95% of patients with HCV infection have achieved sustained virologic response at 12 weeks under the treatment of several pan-genotypic regimens approved for patients with HCV infection. The glecaprevir/pibrentasvir (G/P) regimen has some features that distinguish it from others and is the only 8-week regimen approved for treatment-naive patients and patients experienced in regimens containing (peg)interferon, ribavirin, and/or sofosbuvir, without an HCV NS3/4A protease inhibitor or NS5A inhibitor (except those with genotype 3). This review aims to summarize the efficacy and safety of G/P in HCV-infected patients from clinic trials and real-world studies, including those who have historically been considered difficult to cure.

Efficacy and Safety of Glecaprevir/Pibrentasvir in HCV Patients With Previous Direct-Acting Antiviral Therapy Failures: A Meta-Analysis

Background: Since a greater number of hepatitis C virus (HCV) patients have access to direct-acting antiviral (DAA) based therapies, the number of patients not properly responding to prior DAA regimens is increasing. The objective of this comprehensive analysis was to assess the efficacy and safety of glecaprevir/pibrentasvir (GLE/PIB) in HCV patients who experienced previous DAA therapy failures.

Methods: Bibliographic databases were systematically searched for relevant articles published by November 2020. The main endpoints were sustained viral response after 12 weeks (SVR12), adverse events (AEs; any grade) and severe adverse events (SAEs). Publication bias assessment was performed using funnel plots and the Egger's test.

Results: Fourteen studies consisting of a total of 1,294 subjects were included in this study and the pooled estimate of SVR12, AEs and SAEs rates were 96.8% (95%CI: 95.1–98.2), 47.1% (95%CI: 26.0–69.3), and 1.8% (95%CI: 0.7–3.4), respectively. Subgroup analysis showed that pooled SVR12 rates were 97.9% (95%CI: 96.7–98.9) for Japan and 91.1% (95%CI: 87.3–94.3) for the United States; 95.8% (95%CI: 93.9–97.4) for genotype (GT)1 and 100.0% (95%CI: 99.6–100.0) for GT2; 95.3% (95%CI: 92.4–97.2) for cirrhosis and 96.3% (95%CI: 94.2–97.7) for non-cirrhosis cases. There was no publication bias included this study.

Conclusion: This comprehensive analysis revealed that GLE/PIB is an effective and secure retreatment option for patients who did not optimally respond to DAA treatment, especially the Asian population with GT1-2.

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

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

Efficacy and Safety of Glecaprevir/Pibrentasvir for Chronic Hepatitis C Patients: A Systematic Review and Meta-analysis

Background and Aims: Glecaprevir/pibrentasvir is a pangenotypic regimen recently approved for the treatment of chronic hepatitis C virus (HCV) infection. The objective of the present review was to summarize the findings from clinical trials to understand how patient-related factors influence glecaprevir/pibrentasvir efficacy (sustained virologic response rates at 12 weeks' after treatment [referred to as SVR12]) and safety. Methods: Data from 21 phase III clinical trials were analyzed. Results: The integrated efficacy analysis included 4,817 patients. Findings showed 97.5% of all included patients with chronic HCV achieved SVR12 in the intention-to-treat population. SVR12 rate was >95% across subgroups of interest. The integrated safety analysis included 4,015 patients. Findings showed that 64.1% of patients reported an adverse event, and <0.1% of patients reported a serious adverse event related to glecaprevir/pibrentasvir. Conclusions: These results indicate that the 8- or 12-week glecaprevir/pibrentasvir treatment is effective for patients infected with HCV genotypes 1-6 without or with compensated cirrhosis, with good safety profiles, irrespective of treatment-experience. Glecaprevir/pibrentasvir is a good option for patients with human immunodeficiency virus/HCV coinfection and comorbid HCV and severe renal impairment.

Unmet needs of chronic hepatitis C in the era of direct-acting antiviral therapy

The treatment of chronic hepatitis C (CHC) has been revolutionized in an era of all-oral direct-acting antivirals (DAAs) since 2014. Satisfactory treatment efficacy and tolerability can be provided by novel DAAs. Nevertheless, there are still some unmet needs and emerging issues in the treatment of CHC in the DAA era. Certain hard-to-cure populations are prone to have inferior treatment responses, including patients with severe liver decompensation, active hepatocellular carcinoma (HCC), and hepatitis C virus (HCV) genotype 3 (HCV-3) infection and those who experience multiple DAA treatment failures. Hepatitis B virus (HBV) reactivation during and after DAA treatment has raised concern regarding the use of prophylactic antivirals against HBV throughout DAA treatment. However, the standard strategy for the use of prophylactic antivirals is not uniform across regional guidelines. In the post-sustained virological response (SVR) period, HCC still occurs in a substantial proportion of patients. Due to the relatively short follow-up period, the net benefit of the achievement of an SVR by DAAs in the reduction of extrahepatic manifestations has not yet been determined. Attention must also be paid to HCV reinfection, particularly in high-risk populations. The most critical and unmet need for HCV elimination is the large gap in the HCV care cascade at the population level. To accomplish the World Health Organization (WHO)'s goal for HCV elimination by 2030, the expansion of access to HCV care requires a continuous effort to overcome practical and political challenges.

2020 Taiwan consensus statement on the management of hepatitis C: Part (II) special populations

Hepatitis C virus (HCV) infection is a silent killer that leads to rapid progression of liver cirrhosis and hepatocellular carcinoma (HCC). High prevalence of HCV infection has been reported in Taiwan, especially in high-risk populations including people who inject drugs (PWID) and patients requiring dialysis. Besides, certain populations merit special considerations due to suboptimal outcome, potential drug-drug interaction, or possible side effect. Therefore, in the second part of this 2-part consensus, the Taiwan Association for the Study of the Liver (TASL) proposes the treatment recommendations for the special population in order to serve as guidance to optimizing the outcome in the direct-acting antiviral (DAA) era. Special populations include patients with acute or recent HCV infection, previous DAA failure, chronic kidney disease, decompensated cirrhosis, HCC, liver and other solid organ transplantations, receiving an HCV viremic organ, hepatitis B virus (HBV) and HCV dual infection, HCV and human immunodeficiency virus (HIV) coinfection, active tuberculosis infection, PWID, bleeding disorders and hemoglobinopathies, children and adolescents, and pregnancy. Moreover, future perspectives regarding the management of hepatitis C are also discussed and summarized in this consensus statement.

Hepatitis C and Treatment in Patients with Chronic Kidney Disease

Hepatitis C virus (HCV) is associated with increased mortality and morbidity in patients with chronic kidney disease (CKD). The early detection and treatment of Hepatitis C associated with kidney disease is paramount to preventing the progressive loss of kidney function. HCV treatment until the advent of direct acting anti-viral agents (DAAs) was limited to interferon and ribavirin. Interferon and ribavirin treatment resulted in only modest success but with frequent adverse events and poor tolerability. Furthermore, interferon and ribavirin could not be used in certain patient populations including those with advanced CKD, were on dialysis, or those who have received a kidney transplant. DAAs have now made treatment possible in these sub-groups with a sustained viral response (SVR) of 90-100% and minimal side effects. DAAs have helped increase transplant rates by allowing for the use of HCV positive kidneys in recipients who are HCV negative. Although the choice of DAAs should be carefully considered and based on patient characteristics, concomitant medications, and HCV genotype.

2-((4-Arylpiperazin-1-yl)methyl)benzonitrile Derivatives as Orally Available Inhibitors of Hepatitis C Virus with a Novel Mechanism of Action

Although the direct-acting antivirals revolutionized the hepatitis C virus (HCV) infection treatment in the last decade, more efforts are needed to reach the elimination of HCV in the absence of a vaccine. 4-(Piperazin-1-yl)-2-((p-tolylamino)methyl)-benzonitrile (1) is a modest HCV inhibitor identified from an in-house screening using a HCV-infected Huh7.5 cell culture. Starting from it, the chemical optimization afforded a new 2-((4-arylpiperazin-1-yl)methyl)benzonitrile scaffold with significantly increased antiviral activity against HCV. A highly effective HCV inhibitor, 35 (L0909, EC₅₀ = 0.022 μM, SI > 600), was identified by the structure-activity relationship study. The biological study revealed that L0909 could block HCV replication by acting on the HCV entry stage. The high sensitivity to clinical resistant HCV mutants and synergistic effect with clinical drugs were observed for this compound. The further pharmaceutical studies demonstrated that L0909 is long-lasting, is orally available, and has low toxicity in vivo. These results show L0909 as a promising HCV entry inhibitor for single or combinational therapeutic potential.

Seroconversion of HBsAG coincides with hepatitis A super-infection: A case report

BACKGROUND

Hepatitis B virus (HBV) is a hepatotropic virus that can cause acute and chronic liver damage. According to the world health organization 257 million people are infected with chronic HBV infection worldwide. Super-infection with other hepadnaviruses, including hepatitis A virus (HAV), hepatitis C virus, hepatitis D virus, and hepatitis E virus is associated with increased risk of acute liver failure in patients with chronic HBV.

CASE SUMMARY

Here, we report a case of a 47-year old male patient with HBV-related compensated Child A cirrhosis, who presented with general fatigue, malaise and laboratory signs of acute hepatitis. Although the patient was regularly seen at a specialized university liver unit, the HAV vaccination status was unclear. Acute HAV super-infection was diagnosed by positive serological and polymerase chain reaction analysis. Following acute HAV super-infection, spontaneous HBsAg elimination and development of an anti-HBs titer were observed.

CONCLUSION

This case illustrates the importance of carefully checking the vaccination status. In our patient, unspecific immunological responses to HAV led to functional cure of HBV.

Consensus recommendations for resistance testing in the management of chronic hepatitis C virus infection: Public Health England HCV Resistance Group

The treatment of hepatitis C virus (HCV) infection has been revolutionised by the advent of oral, well-tolerated, direct acting antiviral therapies (DAA), with high cure rates. However, in some scenarios, HCV resistance to antiviral therapies may have an impact on treatment success. Public Health England's HCV Resistance Group was established to support clinicians treating people with HCV, where the issue of resistance may be a factor in clinical decision-making, and this review includes the Group's current recommendations on the use of HCV resistance testing. The authors describe the principles behind and approach to HCV resistance testing and consider evidence from in vitro studies, clinical trials and real world cohorts on the impact of HCV resistance on treatment outcomes for particular DAA regimens. Five scenarios are identified in the UK and similar settings, where, in the Group's opinion, resistance testing should be performed.