HCV RNA quantification using the Cobas Plasma Separation Card as an alternative to EDTA plasma: a prospective multicenter study.

Simplified diagnostic approaches are needed to eliminate hepatitis C by 2030. This prospective multicenter study evaluated dried plasma spots collected with the Cobas® Plasma Separation Card (PSC) versus conventional ethylenediaminetetraacetic acid (EDTA) plasma for hepatitis C virus (HCV) RNA detection and quantification using Cobas HCV (nucleic acid amplification test). Cobas PSCs were spotted with finger prick-collected capillary (PSC capillary) or venous (PSC venous) blood from individuals with known HCV infection status. HCV infection status was based on anti-HCV antibodies and HCV RNA in EDTA plasma. The threshold for clinical sensitivity/specificity was 1000 IU/mL RNA. Quantitative HCV RNA results were compared between EDTA plasma and Cobas PSC samples. Among 224 subjects, 119 had undetectable and 105 had detectable HCV RNA. Clinical sensitivity and specificity versus EDTA plasma were 100% for PSC capillary, and 97.8% and 100%, respectively, for PSC venous. HCV viral loads from PSC capillary and PSC venous were comparable with EDTA plasma. Cobas PSC combined with Cobas HCV showed good diagnostic accuracy versus EDTA plasma; quantitative HCV RNA results were comparable between the two sample types. Cobas PSC sample collection may obviate the need for venipuncture and help to broaden the reach of HCV testing in remote or under-resourced regions.