Can hepatitis C virus core antigen replace quantitative RNA in the assessment of a sustained virologic response?

Abstract

BackgroundThe widespread use of direct-acting antivirals (DAAs) in the treatment of hepatitis C virus (HCV) infection has reduced the need for monitoring HCV-RNA levels because viral kinetics do not predict a sustained virologic response (SVR). However, the performance of cheaper tests, such as the assay to quantify hepatitis C virus core antigen (HCV Ag), has not been determined. Our aim was to assess the accuracy of the HCV core Ag test in predicting the achievement of SVR and its predictive value as a monitoring test in the course of treatment.Patients and methodsThis prospective study was carried out on 90 patients, chronically infected with HCV, who received DAA therapy. Blood samples were collected and the levels of HCV core Ag and HCV-RNA were measured at baseline and at 12 weeks after the end of treatment. We compared the ability of these assays to predict which patients would achieve SVR12.ResultsThe baseline level of HCV-RNA was 1 688 529.6±994 697.3 IU/ml (range: 312 700–3 491 100 IU/ml) and HCV core Ag was 179.2±83.5 pg/ml (range: 33.5–315.6 pg/ml). HCV Ag became undetectable in 92.2% 12 weeks after the end of treatment, whereas HCV-RNA became undetectable in 87.8% at the end of treatment (P<0001). Seventy-nine out of 90 (87.8%) patients achieved SVR12; the test for HCV Ag identified 63.6% of these patients.ConclusionMeasurement of HCV core Ag can monitor the efficacy of DAA therapy for HCV infection. Thus, it can be applied in clinical practice.