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Screening and Treatment for Patients with NS5A Resistance-Associated Variants of Hepatitis C Virus: A Review of Clinical Effectiveness, Cost-Effectiveness, and Guidelines

Last updated: June 27, 2016
Project Number: RC0788-000
Product Line: Rapid Response
Research Type: Other Diagnostics
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the clinical effectiveness of hepatitis C pharmacotherapies containing NS5A inhibitors in direct-acting antiviralnaive patients infected with NS5A resistance-associated variants of hepatitis C virus at baseline?
  2. What is the cost-effectiveness of screening for NS5A resistance-associated variants of hepatitis C virus?
  3. What are the evidence-based guidelines regarding testing or screening and treatment for NS5A resistance-associated variants of hepatitis C virus?

Key Message

The majority of the studies were on hepatitis C virus (HCV) genotype (GT) 1b patients treated with daclatasvir (DCV) plus asunaprevir (ASV). In general, for HCV GT 1b infected patients, who were treated with DCV+ASV, the proportion of patients achieving SVR12 was less in patients with NS5A resistance-associated variants (RAVs) at baseline, compared to those without NS5A RAVs. There were limited studies on treatment regimens including velpatasvir, ledipasvir, elbasvir, and comparing SVR rates in patients infected with HCV GT 1, who had or did not have NS5A RAVs at baseline, hence definitive conclusions are difficult. One guideline recommended that testing for resistance-associated variants that confer decreased susceptibility to NS3 protease inhibitors and to NS5A inhibitors should be conducted for patients with HCV GT 1, regardless of subtype, who have compensated cirrhosis or reasons for urgent retreatment, and have failed either previous treatment with any HCV NS5A inhibitor or HCV protease inhibitor, simeprevir (SMV) plus sofosbuvir (SOF) (with no prior NS5A treatment). Another guideline recommended that patients with HCV GT 1b infection, who were being considered DCV+ASV treatment should be tested for NS5A RAVs prior to treatment initiation.