HCV Core Antigen as an alternative test to Quantitative HCV RNA for assessment of SVR in Chronic HCV infected patients treated with Direct Acting Antiviral agents

Abstract Background and aims Widespread use of direct-acting antiviral (DAA) agents to treat patients with hepatitis C virus (HCV) infection has reduced the need for monitoring of HCV-RNA levels, because viral kinetics do not predict sustained virologic response (SVR) to these drugs. However, the performance of cheaper tests, such as the assay to quantify HCV core antigen (HCV Ag), has not been determined. This study was aimed at investigating the accuracy of the HCV Ag test in predicting which patients receiving DAAs will achieve SVR at week 12 (SVR12). Methods We performed a prospective study on 90 patients, chronically infected with HCV, receiving DAAs therapy from different NCCVH centers in Cairo during the period from August 2017 to June 2018. We collected blood samples and measured the levels of HCV core Ag and HCV-RNA at baseline and 12 weeks after end of treatment. We compared the ability of these assays to predict which patients would have SVR12. Results The median baseline level of HCV-RNA was 1688529.6 ± 994697.3 IU/ml (range, 312700 IU/ml to 3491100 IU/ml) and HCV Ag was 179.2 ± 83.5 pg/ml (range, 33.5 pg/ml to 315.6 pg/ml). HCV Ag became undetectable in 92.2% 12 weeks after the end of treatment. HCV-RNA became undetectable in 87.8% at the end of treatment (P