Economic evaluation of pan-genotypic generic direct-acting antiviral regimens for treatment of chronic hepatitis C in Iran: a cost-effectiveness study

INTRODUCTION

Low-cost generic direct-acting antiviral (DAA) regimens for treatment of hepatitis C virus (HCV) are available in several low-income/middle-income countries, important for treatment scale-up. This study evaluated the cost-effectiveness of genotype-dependent and pan-genotypic DAA regimens in Iran as an example of a resource-limited setting.

METHODS

A Markov model was developed to simulate HCV natural history. A decision tree was developed for HCV treatment, assuming four scenarios, including scenario 1: genotyping, sofosbuvir/ledipasvir (SOF/LDV) for genotype 1, and sofosbuvir/daclatasvir (SOF/DCV) for genotype 3; scenario 2: genotyping, SOF/LDV for genotype 1, and sofosbuvir/velpatasvir (SOF/VEL) for genotype 3; scenario 3: no genotyping and SOF/DCV for all; and scenario 4: no genotyping and SOF/VEL for all. A 1-year cycle length was used to calculate the cumulative cost and effectiveness over a lifetime time horizon. We calculated quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) using a health system perspective. Costs were converted to US dollars using purchasing power parity exchange rate ($PPP). All costs and outcomes were discounted at an annual rate of 3%.

RESULTS

Among people with no cirrhosis, scenario 3 had the minimum cost, compared with which scenario 4 was cost-effective with an ICER of 4583 $PPP per QALY (willingness-to-pay threshold: 9,311 $PPP per QALY). Among both people with compensated or decompensated cirrhosis, scenario 4 was cost saving. In sensitivity analysis, scenario 4 would be also cost-saving among people with no cirrhosis provided a 39% reduction in the cost of 12 weeks SOF/VEL.

CONCLUSION

Initiating all patients on pan-genotypic generic DAA regimens with no pretreatment genotyping was cost-effective compared with scenarios requiring pretreatment HCV genotype tests. Among generic pan-genotypic DAA regimens, SOF/VEL was cost-effective, for people with no cirrhosis and cost-saving for those with cirrhosis.

Treatment of hepatitis C virus infection with direct-acting antiviral agent-based regimens in Iranian patients with hereditary bleeding disorders

BACKGROUND

Chronic hepatitis C (CHC) is one of the most important comorbidities in patients with hereditary bleeding disorders (HBD). The present study aimed at evaluating the effectiveness of direct-acting antiviral agent (DAA)-based interferon-free HCV antiviral regimens in patients with HBD.

PATIENTS AND METHODS

The present study was performed on the patients with HBD and CHC between 2015 and 2019. Sofosbuvir-based interferon-free regimens with or without ribavirin were prescribed to treat HCV infection. The main endpoint of the study was to determine the sustained virologic response (SVR), assessed 12 weeks after the completion of treatment.

RESULTS

A total of 147 patients with a mean age of 41.1 years were enrolled in the study; 4.1% of them were co-infected with HIV, 25.2% had cirrhosis, and 76.9% of them were diagnosed with hemophilia A. HCV genotype-1 includes the largest number (68.1%) of patients. 46.3% of patients were treatment-naïve and others had a treatment history with interferon-based regimens. Out of 147 patients, 15 patients were lost to follow-up during treatment or for SVR evaluation or discontinued treatment. 132 subjects completed treatment and were evaluated for SVR, 12 weeks after the completion of treatment. All of the patients achieved SVR 12 (SVR rate: 100%, 95% CI 97.2-100%).

CONCLUSION

Hepatitis C DAA-based regimens are the effective treatments for CHC in patients with HBD, regardless of the treatment modifiers such as previous treatment experience, cirrhosis, HIV co-infection, and HCV genotype.

Prevalence of Naturally-Occurring NS5A and NS5B Resistance-Associated Substitutions in Iranian Patients With Chronic Hepatitis C Infection

BACKGROUND

Hepatitis C virus (HCV), non-structural 5A (NS5A), and non-structural 5B (NS5B) resistance-associated substitutions (RASs) are the main causes of failure to direct-acting antiviral agents (DAAs). NS5A and NS5B RASs can occur in patients with HCV infection naturally and before exposure to DAAs.

OBJECTIVES

This study aimed to evaluate naturally-occurring NS5A and NS5B RASs in Iranian patients with HCV genotype 1a (HCV-1a) and -3a infections.

METHODS

In this cross-sectional study, viral RNA was extracted from serum specimens. NS5A and NS5B regions were amplified using RT-PCR followed by DNA sequencing. The results of nucleotide sequences were aligned against reference sequences of HCV-1a and -3a and the amino acid substitutions were analyzed using geno2pheno [hcv] web application.

RESULTS

Among 135 patients with hepatitis C, NS5A amino acid substitutions/RASs were identified in 26.4% and 15.9% of patients with HCV-1a and -3a infections, respectively. The identified amino acid substitutions/RASs in the NS5A region of patients with HCV-1a infection were M28T/V/I 11.1%, Q30R/H 4.2%, L31M 1.4%, and H58Y/P/C/D/Q/S/T 16.7%. Y93H substitution was not found in HCV-1a sequences. In patients with HCV-3a infection, NS5A amino acid substitutions/RASs were A30T/K 9.5%, L31F 1.6%, P58S/T/C 3.2%, Y93H 3.2%, and Y93N 3.2%. No resistance substitutions were identified in NS5B sequences from patients with HCV-1a and -3a infections.

CONCLUSION

In this study, baseline amino acid substitutions/RASs were only identified in the NS5A region in Iranian patients with HCV-1a and -3a infections, and the prevalence of these amino acid substitutions/RASs were in accordance with similar studies. There were no RASs in the HCV-1a and -3a NS5B region.

Pooled Prevalence of NS5A Resistance-Associated Substitutions in Chronic HCV Genotype 3 Infection: A Study Based on Deposited Sequences in GenBank

Using direct-acting antiviral agents (DAAs) against hepatitis C virus (HCV) infection results in a high treatment response rate. However, several factors can significantly alter this outcome such as resistance-associated substitutions (RASs) in HCV NS5A gene. This study aimed to evaluate the prevalence of naturally occurring RASs of NS5A in HCV genotype 3 (HCV-3) sequences isolated from individuals with chronic HCV-3 infection. All the registered sequences in the GenBank under "NS5A" AND "Hepacivirus C" query were evaluated and screened, those which followed our inclusion criteria were enrolled in our pooled analysis. The retrieved sequences of included studies were evaluated for substitutions, RASs, and RASs conferring >100 resistance fold change (RASs >100 × ) in NS5A amino acid positions 24, 28, 30, 31, 62, 92, and 93. From 7 enrolled studies, a total of 370 HCV-3a isolates were retrieved and investigated. Forty-eight (13.0%, 95% CI = 9.9-16.8%) isolates harbored NS5A RASs. Moreover, Y93H was the only NS5A RAS >100 × observed in 13 (3.5%, 95% CI = 2.0-5.9%) retrieved sequences. The low frequency of naturally occurring NS5A RASs, especially those with clinical relevance (RASs >100 × ), among individuals with HCV-3 infection and the high rate of treatment response to DAAs suggest not to investigate every individual with HCV-3 infection for NS5A RASs before treatment.

Performance of a rapid diagnostic test for screening of hepatitis C in a real-life prison setting

BACKGROUND

Hepatitis C virus (HCV) point-of-care testing using rapid diagnostic test (RDT) is the solution for large-scale, feasible, fast and reliable screening of HCV infection.

OBJECTIVES

The aim of this study was to evaluate the diagnostic performance of HCV RDT for screening of HCV infection in a real-life prison setting.

STUDY DESIGN

This study was conducted on individuals admitted and incarcerated in the Central Prison of Karaj, 2017-2018. For all inmates, anti-HCV testing using a RDT on finger-stick blood in the prison and ELISA at the laboratory were performed. For evaluation of reproducibility, more than 1000 cases were recruited for re-evaluation of the HCV RDT using anticoagulated blood in the laboratory.

RESULTS

Among 1788 participants, 76 (4.25%) and 106 (5.93%) were positive for anti-HCV using RDT and ELISA, respectively. Among 34 cases with discordant results using the RDT and ELISA, 17 were the result of testing error in prison, 7 false positive of ELISA and 10 false negative of RDT in individuals with HCV spontaneous clearance. The sensitivity of the RDT with inclusion of testing error in prison for detection of anti-HCV was 75%. However, with exclusion of testing error in prison and considering HCV RNA as the reference method for diagnosis of current HCV infection the sensitivity reached 100%. The RDT was 100% reproducible using both evaluations in prison and the laboratory.

CONCLUSIONS

The RDT is a reliable and feasible method for screening of anti-HCV in settings such as a prison. However, the testing should be performed in a standard procedure to have the optimal diagnostic performance.

Prevalence of hepatitis C virus NS5A resistance-associated substitutions in chronic infection with genotype 1: A pooled analysis based on deposited sequences in GenBank

INTRODUCTION

Resistance-associated substitutions (RASs) in the NS5A gene of hepatitis C virus (HCV) has been studied as one of the predictors of response to NS5A inhibitor-containing regimens. This study aimed to evaluate the prevalence of pre-treatment naturally-occurring NS5A RASs in HCV isolates from patients with chronic HCV genotype 1 (HCV-1) infection retrieved from GenBank.

METHODS

In the search procedure, the studies with published HCV-1 NS5A sequence in GenBank were screened and evaluated for inclusion in the pooled analysis. The sequences of the included studies were retrieved from GenBank and evaluated for substitutions in amino acid positions24, 26, 28, 29, 30, 31, 32, 38, 58, 62, 92 and 93 of HCV NS5A including RASs and RASs conferring >100 resistance fold change (RASs >100X).

RESULTS

In the pooled analysis, 2409 isolates from patients with HCV-1 infection were included, consisting 1305 (54.2%) HCV-1a and 1104 (45.8%) HCV-1b isolates. The prevalence of NS5A RASs and RASs >100X were 16.0% (95%CI = 14.6%-17.5%) and 4.7% (95%CI = 3.9%-5.6%), respectively. The NS5A RASs were more frequently observed in HCV-1b isolates than in HCV-1a isolates (P < 0.001).

CONCLUSION

The naturally-occurring HCV NS5A RASs especially those with clinical relevance (RASs >100X) are observed in a small (4.7%) number of patients with HCV-1 infection.

Hepatitis C resistance to NS5A inhibitors: Is it going to be a problem?

Treatment of hepatitis C virus (HCV) infection has evolved greatly through the recent decade. The availability of direct-acting antiviral agents (DAAs) targeting the functional proteins of HCV has resulted in the introduction of DAA-based combination therapies, providing an optimal rate of treatment success. Among the DAAs, NS5A inhibitors are used in most of the introduced and approved HCV antiviral regimens. Resistance-associated substitutions (RASs) are amino acid substitutions in HCV protein sequences that result in decreased antiviral efficacy of the HCV DAAs. Among the HCV RASs, the NS5A RASs were found to effectively modify and decrease treatment response to NS5A inhibitor-containing regimens. As a baseline predictor of treatment response, NS5A RAS draws attention for pretreatment testing in targeted patient groups. Given NS5A RASs are either naturally-occurring or DAA-selected, the application of NS5A RAS testing can be considered in two settings of NS5A inhibitor-naïve patients and NS5A inhibitor-experienced patients. Less than 5% of NS5A inhibitor-naïve patients harbor naturally-occurring NS5A RAS with high resistance level (> 100X resistance fold-change). In NS5A inhibitor-naïve patients, NS5A RAS testing accompanied by treatment optimization cannot increase treatment response more than 2%-3%, while in NS5A inhibitor-experienced patients, > 75% are found to have NS5A RASs > 100X and NS5A RAS testing in this group of patients seems to be reasonable. This editorial will address the debate on the application of NS5A RAS testing and will discuss if the NS5A RAS testing has any role in clinical management of hepatitis C.