Sofosbuvir/velpatasvir regimen promises an effective pan-genotypic hepatitis C virus cure

Morphometric, biochemical and histopathological effects of sofosbuvir (sovaldi) on testes of adult male albino rats

Sofosbuvir treatment regimens for chronic HCV infection have recently been linked to extra hepatic side effects. This study aimed to show how sofosbuvir affected the adult male albino rat testis. Forty adult male albino rats were used. The rats were equally split into two main groups (I and II), then each group subdivided into two subgroups (A and B). Each rat in group I (control) received 0.5 ml of distilled water every day for four weeks. Each rat in group II (sofosbuvir-treated) received 0.5 ml of distilled water containing 7.2 mg of sofosbuvir every day for four weeks. After four weeks (subgroups IA and IIA) and eight weeks (subgroups IB and IIB) of treatment, the rats were sacrificed. Histological, biochemical, and morphometric studies on the testes were conducted. The data were analyzed. Examination of testes of sovaldi treated group revealed histopathological changes. Biochemical and morphometric analysis showed reduced levels of reduced glutathione and seminiferous tubule epithelial height respectively. Following a 4-week drug withdrawal period, the testes only partially recovered. We concluded that sofosbuvir induced deteriorating changes in the adult male albino rats' testes. These changes were proved by histological and biochemical studies. These changes were incompletely reversible after cession of treatment. Researches investigating the effect of adding drugs that have antioxidant properties during sofosbuvir therapy are recommended.

Real-world treatment outcome of direct-acting antivirals and patient survival rates in chronic hepatitis C virus infection in Eritrea

Reliable real-world data on direct acting anti-retroviral (DAA) uptake and treatment outcomes are lacking for patients with hepatitis C virus (HCV) in sub-Saharan Africa. This study provides data on HCV DAA-based treatment outcomes, mortality, loss-to-follow up, and associated factors among patients in Eritrea. A multicenter retrospective observational cohort study was conducted in two tertiary hospitals in Asmara, Eritrea. A structured checklist was used to collect data from patient's cards. Descriptive and inferential statistics used included means (± Standard deviation (SD), medians (Interquartile range (IQR), chi-squire (χ2), Kaplan-Meier estimates, and multivariate Cox proportional hazard models. A total of 238 patients with median age of 59 years (IQR 50-69 years) were enrolled in the study. Out of the 227 patients initiated on treatment, 125 patients had viral load measurements at 12 weeks after end of treatment (EOT) whereas 102 patients had no viral load measurements at 12 weeks EOT. Among the patients with HCV RNA data post-EOT 12, 116 (92.8%) had sustained viral response (SVR). The prevalence of death and loss-to-follow up (LTFU) were (7.5%, 95% CI 1.7-4.1) and 67 (28.1%, 95% CI 22.3-33.9) translating into an incidence of 1.1 (95% CI 0.8-1.5) per 10,000 person days. Independent predictors of LTFU included the enrollment year (2020: aHR = 2.2, 95% CI 1-4.7; p value = 0.04); Hospital (Hospital B: aHR = 2.2, 95% CI 1-4.7; p value = 0.03) and the FIB-4 score (FIB-Score < 1.45: aHR = 3.7, 95% CI 1.2-11.5; p value = 0.02). The SVR rates achieved in this cohort were high. However, high LTFU and high mortality driven largely by late presentation and suboptimal population screening/case finding, were uncovered. These challenges can be addressed by test-and-treat programs that simultaneously prioritize programmatic screening, decentralization of care, and better patient tracking in the HCV care cascade.

Cost-utility Analysis of Second-generation Direct-acting Antivirals for Hepatitis C

Background: Hepatitis C virus (HCV) can lead to increased mortality, disability, and liver transplantation if left untreated, and it is associated with a possible increase in disease burden in the future, all of which would surely have a significant impact on the health system. New antiviral regimens are effective in the treatment of the disease yet expensive. Objectives: The purpose of the present study was to assess the cost-effectiveness of three medication regimens, namely, ledipasvir/sofosbuvir (LDV/SOF), velpatasvir/sofosbuvir, and daclatasvir/sofosbuvir (DCV/SOF) for HCV patients with genotype 1 in Iran. Methods: A Markov model with a lifetime horizon was developed to predict the costs and outcomes of the three mentioned medication therapy strategies. The final outcome of the study was quality-adjusted life-years (QALYs), which was obtained using the previously published studies. The study was conducted from the perspective of the Health Ministry; therefore, only direct medical costs were estimated. The results were provided as the incremental cost-effectiveness ratio (ICER) per QALY. Ultimately, the one-way and probabilistic sensitivity analyses were used to measure the strength of study results. Results: The results showed that the QALYs for LDV/SOF, DCV/SOF, and VEL/SOF were 13.25, 13.94, and 14.61, and the costs were 4,807, 7,716, and 4,546$, respectively. The VEL/SOF regimen had lower costs and higher effectiveness than the LDV/SOF and DCV/SOF regimens, making it a dominant strategy. The tornado diagram results showed that the study results had the highest sensitivity to chronic hepatitis C (CHC) and compensated cirrhosis (CC) state costs. Moreover, the scatter plots showed that the VEL/SOF was the dominant therapeutic strategy in 73% of the simulations compared to LDV/SOF and 66% of the simulations compared to DCV/SOF; moreover, it was in the acceptable region in 92% of the simulations and below the threshold. Therefore, it was considered the most cost-effective strategy. Moreover, the results showed that DCV/SOF was in the acceptable region below the threshold in 69% of the simulations compared to LDV/SOF. Therefore, the DCV/SOF regimen was more cost-effective than LDV/SOF. Conclusions: According to the present study results, it is suggested that the VEL/SOF regimen be used as the first line of therapy in patients with HCV genotype 1. Moreover, DCV/SOF can be the second-line medication regimen.

Trends and strategies to combat viral infections: A review on FDA approved antiviral drugs

The infectious microscopic viruses invade living cells to reproduce themselves, and causes chronic infections such as HIV/AIDS, hepatitis B and C, flu, etc. in humans which may lead to death if not treated. Different strategies have been utilized to develop new and superior antiviral drugs to counter the viral infections. The FDA approval of HIV nucleoside reverse transcriptase inhibitor, zidovudine in 1987 boosted the development of antiviral agents against different viruses. Currently, there are a number of combination drugs developed against various viral infections to arrest the activity of same or different viral macromolecules at multiple stages of its life cycle; among which majority are targeted to interfere with the replication of viral genome. Besides these, other type of antiviral molecules includes entry inhibitors, integrase inhibitors, protease inhibitors, interferons, immunomodulators, etc. The antiviral drugs can be toxic to human cells, particularly in case of administration of combination drugs, and on the other hand viruses can grow resistant to the antiviral drugs. Furthermore, emergence of new viruses like Ebola, coronaviruses (SARS-CoV, SARS-CoV-2) emphasizes the need for more innovative strategies to develop better antiviral drugs to fight the existing and the emerging viral infections. Hence, we reviewed the strategic enhancements in developing antiviral drugs for the treatment of different viral infections over the years.

Discovery of 2-aminoisobutyric acid ethyl ester (AIBEE) phosphoramidate prodrugs for delivering nucleoside HCV NS5B polymerase inhibitors

Our HCV research program investigated novel 2'-dihalogenated nucleoside HCV polymerase inhibitors and identified compound 1, a 5'-phosphoramidate prodrug of 2'-deoxy-2'-α-bromo-β-chloro uridine. Although 1 had a favorable in vitro activity profile in HCV replicons, oral dosing in dog resulted in low levels of the active 5'-triphosphate (TP) in liver. Metabolism studies using human hepatocytes provided a simple assay for screening alternative phosphoramidate prodrug analogs. Compounds that produced high TP concentrations in hepatocytes were tested in dog liver biopsy studies. This method identified 2-aminoisobutyric acid ethyl ester (AIBEE) phosphoramidate prodrug 14, which provided 100-fold higher TP concentrations in dog liver in comparison to 1 (4 and 24 h after 5 mg/kg oral dose).

Epidemiología, consumo de recursos y costos del manejo médico de la Hepatitis C en Argentina, Colombia, Uruguay y Venezuela

OBJECTIVE

To describe the epidemiology, the consumption of resources and the relevant costs in the management of hepatitis C in four Latin American countries: Argentina, Colombia, Uruguay and Venezuela.

STUDY DESIGN

Bibliographic review, study of costs and elicitation by experts METHODS: A literature search was carried out to collect epidemiological and cost data for the management of the disease. Information was additionally elicited with hepatologists from each country using the modified Delphi Panel technique. For the estimation of costs, the perspective of the health system was adopted. The direct medical costs of the different stages associated with the natural history of the disease were considered through micro-costing.

RESULTS

Extensive epidemiological and economic information is provided for the four countries under study. The age range between 40 and 60 years was the most affected. The frequency of genotypes showed a predominance of genotype 1 (68 to 88%), genotype 1b having been reported as the most prevalent in Argentina and Colombia and 1a in Uruguay and Venezuela. The costs of drug regimens, associated health events and adverse events present important differences in the four selected countries of Latin America.

CONCLUSION

Hepatitis C presents a high burden of disease in the countries under study, and its management imposes significant costs on health systems.

Genotype distribution in relation to viral load in a large cohort of Indian patients with chronic hepatitis C virus infection: A retrospective analysis

INTRODUCTION

Hepatitis C virus (HCV) displays high genetic diversity, characterized by regional variations in the prevalence of genotype posing challenges to the development of vaccines and definitive treatment. Very few reports exist on the distribution and frequency change of HCV genotypes in India. In the present retrospective study, we aimed to understand the distribution pattern of HCV genotypes and viral load among HCV-infected patients attending the Asian Institute of Gastroenterology, Hyderabad, India, a tertiary care hospital.

METHODS

Patients referred to the Hepatology Department from January 2009 to December 2015 were screened for this study. Eight hundred and sixty-two chronic HCV patients were included in this study. Genotyping was performed using type-specific probe-based hybridization assay and viral load was estimated by real-time polymerase chain reaction.

RESULTS

Out of 862 patients, genotype 1 was detected predominantly in 392 (45.5%), followed by genotype 3 in 344 (39.9%) patients; genotypes 4, 6, and 2 were detected in 115 (13.3%), 8 (0.9%), and 3 (0.3%) patients, respectively. The number of patients having genotype 1 increased in frequency while genotype 3 became less from the year 2009 to 2015. Patients having genotype 1 had significantly (p < 0.0001) higher viral load compared with the patients infected with other genotypes.

CONCLUSION

Our study results demonstrate a change in HCV genotypic distribution pattern from genotypes 3 to 1 during the span of 7 years in patients referred to our hospital. In the light of the reported difference in the pathogenic potential of various HCV genotypes, detection of HCV genotype appears to be still essential for better patient management.

A retrospective study of the efficacy of sofosbuvir plus NS5A inhibitors for patients with hepatitis C virus genotype-2 chronic infection

BACKGROUND

A combination of sofosbuvir (SOF)+NS5A inhibitor therapies is the main treatment for patients with hepatitis C virus (HCV) genotype-2 (GT-2) chronic infection, but the data are rarely reported in China. This study aimed to investigate the virological response and liver fibrosis improvement among GT-2 patients receiving SOF+NS5A inhibitors.

PATIENTS AND METHODS

In this retrospective study, patients who received SOF+NS5A inhibitors between March 2016 and July 2017 were recruited. The treatment duration was 12 weeks and the treatment strategies included SOF+daclatasvir, SOF/ledipasvir, and SOF/velpatasvir. The primary endpoint was a sustained virologic response (serum HCV RNA undetectable) at week 12 after the end of therapy and the secondary endpoint was the improvement in liver stiffness and scores of apartate aminotransferase to platelet ratio index and fibrosis-4.

RESULTS

A total of 30 GT-2 patients were enrolled, with 13 (43.3%) patients in SOF+daclatasvir, 13 (43.3%) patients in SOF/ledipasvir, and four (13.3%) patients in SOF/velpatasvir. All patients [30/30 (100%)] achieved SVR, irrespective of treatment regimens and degree of liver fibrosis. After the treatment, liver fibrosis scores of apartate aminotransferase to platelet ratio index (2.27±2.14 vs. 0.89±0.77, P=0.003) and fibrosis-4 (1.17±1.22 vs. 0.42±0.25, P=0.013) were both significantly lower than those before treatment.

CONCLUSION

SOF+NS5A inhibitor therapies may induce an excellent virological response and fibrosis improvement in HCV GT-2-infected patients.

Update on global epidemiology of viral hepatitis and preventive strategies

Viral hepatitis is one of the major public health concerns around the world but until recently it has drawn little attention or funding from global health policymakers. Every year 1.4 million people die from viral hepatitis-related cirrhosis and liver cancer. However, the majority of the infected population are unaware of their condition. This population have significant obstacles to overcome such as lack of awareness, vulnerability, increased migration, disease stigma, discrimination, as well as poor health resources, conflict in policy development and program implementation. Despite implementing infection control measures over the last few decades eradication or significant disease reduction remains elusive. This study aims to present the current global prevalence status and examines potential elimination strategies. The information for this research were obtained through a systematic review, published scientific literatures, the official websites of various government organisations, international public health organisations and internationally recognised regulatory bodies over a period of 40 years between 1978 and 2018.

Direct-acting antiviral treatment of acute hepatitis C virus infections

INTRODUCTION

Hepatitis C contributes to significant morbidity and mortality worldwide. AHCV is defined as documented infection within 6 months of exposure. Treating acute hepatitis C virus (AHCV) with direct-acting antiviral agents in persons who inject drugs, HIV-positive men who have sex with men, and patients who acquire HCV nosocomially can contribute to the elimination of disease globally, preclude the morbidity and mortality of chronic disease, and prevent further transmission. Areas covered: In this review, we describe the epidemiology of AHCV, its natural history, the considerations involved in the decision of whether to treat AHCV, and the most current DAA therapy guidelines. PubMed was queried using key words and bibliographies were evaluated for relevant articles. Expert commentary: Despite the obvious benefits of AHCV treatment, clinical management is limited by the ability to identify asymptomatic cases and the absence of fully supported guidelines. However, clinical research is advancing and identifying specific regimens, decreasing treatment durations, and creating strategies to target at risk groups and screen for AHCV.

A Closing Chapter: Hepatitis C Genotype 3 Elimination in Liver Transplant; Sofosbuvir/Daclatasvir in a Hard-to-Treat Population

OBJECTIVES

Historically, hepatitis C virus genotype 3 infection has not been as hard to treat as genotype 1 using interferon-based therapy. Now, genotype 3 infection can be treated using interferon-free regimes such as the combination of sofosbuvir and daclatasvir, which is a highly successful and reliable therapeutic option before liver transplant. However, real world data are rather limited regarding the use of antivirals (sofosbuvir/daclatasvir) for hepatitis C virus genotype 3 recurrence after liver transplant. Here, we present the results of antiviral treatment with sofosbuvir and daclatasvir in patients with genotype 3 recurrence after liver transplant and also viewed published data, to finally close the chapter on genotype 3 elimination.

MATERIALS AND METHODS

We analyzed 11 patients who received liver transplants due to hepatitis C virus genotype 3-associated cirrhosis at our center. Two patients were nadve for any antiviral therapy. All patients received antiviral treatment with sofosbuvir/daclatasvir for 12 weeks after liver transplant, with 1 patient also having ribavirin. The endpoint was hepatitis C virus RNA-free survival after 12 weeks of therapy. Secondary endpoints were preservation of renal and liver function and incidence of adverse events.

RESULTS

All patients were free of hepatitis C virus RNA by at least 8 weeks after therapy initiation. Elevated transaminases and gamma-glutamyltransferase at the beginning of therapy normalized quickly during treatment. Synthesis and excretion were stable at all dates. Patients displayed no severe adverse effects, especially regarding renal function and blood counts. Sustained virologic response rates at week 12 were achieved in all 11 patients.

CONCLUSIONS

Hepatitis C virus could be eliminated in all patients after liver transplant with 12-week sofosbuvir/daclatasvir therapy. Sofosbuvir combined with daclatasvir is safe and reliable for recurrent hepatitis C virus genotype 3 infection. Our results have closed the chapter on genotype 3 recurrence after liver transplant in our outpatient clinic.

Short article: Alcohol and substance use, race, and insurance status predict nontreatment for hepatitis C virus in the era of direct acting antivirals: a retrospective study in a large urban tertiary center

OBJECTIVE

Direct acting antivirals (DAAs) have overcome many long-standing medical barriers to hepatitis C virus (HCV) treatment (i.e. host characteristics and medical contraindications) and treatment outcome disparities that were associated with interferon regimens. The public health and clinical benefit of current and forthcoming DAA discoveries will be limited if efforts are not made to examine racial, psychological, and socioeconomic factors associated with being treated with DAAs. This study examined racial, psychological, and socioeconomic factors that facilitate and inhibit patients receiving DAAs for HCV.

PATIENTS AND METHODS

This was a single-center retrospective cohort study at a large urban tertiary center of patients (n=747) who were referred for evaluation and treatment of HCV.

RESULTS

Sixty-eight percent of patients were non-Hispanic White, 31% were African American, and 1% were of other ethnicities. The majority of patients received treatment, but 29% (218/747) did not. Patients who were older [odds ratio (OR)=1.02, 95% confidence interval (CI): 1.01-1.04] and insured (OR=2.73, 95% CI: 1.12-6.97) were more likely to receive HCV treatment. Patients who were African American (OR=0.46, 95% CI: 0.46-1.06), used drugs (OR=0.09, 95% CI: 0.04-0.17), smoked (OR=0.55, 95% CI: 0.37-0.81), and used alcohol (OR=0.11, 95% CI: 0.06-0.20) were less likely to receive HCV treatment.

CONCLUSION

Though DAAs have eliminated many historically, long-standing medical barriers to HCV treatment, several racial, psychological and socioeconomic barriers, and disparities remain. Consequently, patients who are African American, uninsured, and actively use drugs and alcohol will suffer from increased HCV-related morbidity and mortality in the coming years if deliberate public health and clinical efforts are not made to facilitate access to DAAs.

Predictors Associated with Increase in Skeletal Muscle Mass after Sustained Virological Response in Chronic Hepatitis C Treated with Direct Acting Antivirals

Aims: We aimed to examine changes in skeletal muscle mass in chronic hepatitis C (CHC) patients undergoing interferon (IFN)-free direct acting antivirals (DAAs) therapy who achieved sustained virological response (SVR). Patients and methods: A total of 69 CHC patients treated with DAAs were analyzed. We compared the changes in skeletal muscle index (SMI) using bio-impedance analysis at baseline and SMI at SVR. SMI was calculated as the sum of skeletal muscle mass in upper and lower extremities divided by height squared (cm²/m²). Further, we identified pretreatment parameters contributing to the increased SMI at SVR. Results: SMI in males at baseline ranged from 6.73 to 9.08 cm²/m² (median, 7.65 cm²/m²), while that in females ranged from 4.45 to 7.27 cm²/m² (median, 5.81 cm²/m²). At SVR, 36 patients (52.2%) had increased SMI as compared with baseline. In the univariate analysis, age (p = 0.0392), hyaluronic acid (p = 0.0143), and branched-chain amino acid to tyrosine ratio (BTR) (p = 0.0024) were significant pretreatment factors linked to increased SMI at SVR. In the multivariate analysis, only BTR was an independent predictor linked to the increased SMI at SVR (p = 0.0488). Conclusion: Pretreatment BTR level can be helpful for predicting increased SMI after SVR in CHC patients undergoing IFN-free DAAs therapy.

Chemical genetics-based development of small molecules targeting hepatitis C virus

Hepatitis C virus (HCV) infection is a major worldwide problem that has emerged as one of the most significant diseases affecting humans. There are currently no vaccines or efficient therapies without side effects, despite today's advanced medical technology. Currently, the common therapy for most patients (i.e. genotype 1) is combination of HCV-specific direct-acting antivirals (DAAs). Up to 2011, the standard of care (SOC) was a combination of peg-IFNα with ribavirin (RBV). After approval of NS3/4A protease inhibitor, SOC was peg-IFNα and RBV with either the first-generation DAAs boceprevir or telaprevir. In the past several years, various novel small molecules have been discovered and some of them (i.e., HCV polymerase, protease, helicase and entry inhibitors) have undergone clinical trials. Between 2013 and 2016, the second-generation DAA drugs simeprevir, asunaprevir, daclatasvir, dasabuvir, sofosbuvir, and elbasvir were approved, as well as the combinational drugs Harvoni^®, Zepatier^®, Technivie^®, and Epclusa^®. A number of reviews have been recently published describing the structure-activity relationship (SAR) in the development of HCV inhibitors and outlining current therapeutic approaches to hepatitis C infection. Target identification involves studying a drug's mechanism of action (MOA), and a variety of target identification methods have been developed in the past few years. Chemical biology has emerged as a powerful tool for studying biological processes using small molecules. The use of chemical genetic methods is a valuable strategy for studying the molecular mechanisms of the viral lifecycle and screening for anti-viral agents. Two general screening approaches have been employed: forward and reverse chemical genetics. This review reveals information on the small molecules in HCV drug discovery by using chemical genetics for targeting the HCV protein and describes successful examples of targets identified with these methods.