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The cost-effectiveness of testing for NS5a resistance-associated polymorphisms at baseline in genotype 1a-infected (treatment-naive and treatment-experienced) subjects treated with all-oral elbasvir/grazoprevir regimens in the United States.

ABSTRACT:

Background

The presence of baseline NS5A resistance-associated variants (RAVs) impacted treatment response in HCV genotype 1a (GT1a)-infected patients treated with elbasvir/grazoprevir (EBR/GZR) for 12 weeks, but not patients treated with EBR/GZR and ribavirin (RBV) for 16 weeks.

Aims

To assess the cost-effectiveness of baseline testing for NS5A RAVs in EBR/GZR-treated patients compared without testing, and with current treatments for GT1a patients.

Methods

We simulated the course of treatment with EBR/GZR, ledipasvir/sofosbuvir (LDV/SOF) and ombitasvir/paritaprevir/ritonavir+dasabuvir (3D) with or without RBV and natural history of disease of GT1a patients. Treatment-related data from clinical trials were used in a state-transition model of the natural history of chronic HCV GT1a infection and liver disease to project lifetime costs (US$2015) and quality-adjusted life years (QALY). Other clinical and economic inputs were estimated from published sources. We conducted base case and sensitivity analyses.

Results

RAVs testing-guided treatment with EBR/GZR resulted in more QALYs than EBR/GZR without testing, 3D+RBV, or LDV/SOF8. This strategy was cost-saving relative to 3D+RBV or LDV/SOF8 and was cost-effective compared with EBR/GZR without testing. LDV/SOF12 was not cost-effective compared with the EBR/GZR RAVs testing-based strategy. Treatment with EBR/GZR guided by RAVs testing is the most effective regimen among treatment-experienced patients without cirrhosis and cirrhotic patients. In sensitivity analysis, RAVs testing was cost-effective in 48-55% and 63-85% among noncirrhotic and cirrhotic patients respectively.

Conclusions

RAVs testing before treatment with EBR/GZR is likely to be a cost-effective alternative to the use of EBR/GZR without testing, LDV/SOF, or 3D among GT1a treatment-naïve or treatment-experienced patients.

SUBMITTER: Elbasha EH

PROVIDER: S-EPMC6680317 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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The cost-effectiveness of testing for NS5a resistance-associated polymorphisms at baseline in genotype 1a-infected (treatment-naïve and treatment-experienced) subjects treated with all-oral elbasvir/grazoprevir regimens in the United States.

Elbasha E H EH Robertson M N MN Nwankwo C C

Alimentary pharmacology & therapeutics 20161201 3

<h4>Background</h4>The presence of baseline NS5A resistance-associated variants (RAVs) impacted treatment response in HCV genotype 1a (GT1a)-infected patients treated with elbasvir/grazoprevir (EBR/GZR) for 12 weeks, but not patients treated with EBR/GZR and ribavirin (RBV) for 16 weeks.<h4>Aims</h4>To assess the cost-effectiveness of baseline testing for NS5A RAVs in EBR/GZR-treated patients compared without testing, and with current treatments for GT1a patients.<h4>Methods</h4>We simulated the ...[more]

PMID: 27910116

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