Performance Evaluation of Access HIV Combo V2 Assay

Abstract

Background:The recently introduced 4th generation HIV assay, Access HIV Combo V2 (Bio-Rad Laboratories, USA), can detect the HIV-2 p26 antigen, which has not been targeted by other 4th generation HIV assays. We evaluated the clinical utility of the Access HIV Combo V2 assay. Methods: A total of 1,100 negative samples evaluated using the ARCHITECT HIV Ag/Ab Combo assay (Abbott Laboratories, USA) in Seoul National University Hospital (SNUH) during September 2021 and October 2021 were included. Additional 100 positive samples, including 25 sera from SNUH that showed positive ARCHITECT HIV Ag/Ab Combo and western blot/RNA assay results, along with 60 sera from Chung-Ang University Hospital Biobank and 15 commercial samples (9 HIV-1 p24 antigen-, 3 HIV-2 antibody-, 3 HIV-2 p26 antigen-positive), were included. Three seroconversion panel samples were tested for seroconversion sensitivity. Three levels (NC, PC1, and PC2) of QC materials were tested for precision 5 times a day for 5 consecutive days, and carry-over was also evaluated. Results: Sensitivity and specificity of Access HIV Combo V2 were 100.00% (95% CI: 96.38-100.0%) and 99.82% (95% CI: 99.34-99.98%), respectively. Access HIV Combo V2 showed seroconversion sensitivity comparable to that of ARCHITECT HIV Ag/Ab Combo and Elecsys HIV combi PT (Roche Diagnostics, Germany). Within-laboratory CV were 9.5%, 3.7%, and 3.9% for NC, PC1, and PC2, respectively, and no carry-over was observed. Conclusions: Access HIV Combo V2 assay showed excellent sensitivity and specificity, good precision, and no carry-over. Its seroconversion sensitivity was comparable to that of existing 4th generation HIV assays.