Clinical Evaluation of BD Veritor SARS-CoV-2 Point-of-Care Test Performance Compared to PCR-Based Testing and versus the Sofia 2 SARS Antigen Point-of-Care Test

Abstract

Objectives The clinical performance of the BD Veritor™ System for Rapid Detection of SARS-CoV-2 nucleocapsid antigen (Veritor), a chromatographic immunoassay used for SARS-CoV-2 point-of-care testing, was evaluated using nasal specimens from individuals with COVID-19 symptoms. Methods: Two studies were completed to determine clinical performance. In the first study, nasal specimens and either nasopharyngeal or oropharyngeal specimens from 251 participants with COVID-19 symptoms (≤7 days from symptom onset [DSO]), ≥18 years of age, were utilized to compare Veritor with the Lyra® SARS-CoV-2 PCR Assay (Lyra). In the second study, nasal specimens from 361 participants with COVID-19 symptoms (≤5 DSO), ≥18 years of age, were utilized to compare performance of Veritor to that of the Sofia® 2 SARS Antigen FIA test (Sofia 2). Positive, negative, and overall percent agreement (PPA, NPA, and OPA, respectively) were the primary outcomes. Results: In study 1, PPA for Veritor, compared to Lyra, ranged from 81.8%-87.5% for 0-1 through 0-6 DSO ranges. In study 2, Veritor had a PPA, NPA, and OPA of 97.4%, 98.1%, and 98.1%, respectively, with Sofia 2. Discordant analysis showed one Lyra positive missed by Veritor and five Lyra positives missed by Sofia 2; one Veritor positive result was negative by Lyra. Conclusions: Veritor met FDA-EUA acceptance criteria for SARS-CoV-2 antigen testing (≥80% PPA point estimate) for the 0-5 and 0-6 DSO ranges. Veritor and Sofia 2 showed a high degree of agreement for SARS-CoV-2 detection. The Veritor test allows for more rapid COVID-19 testing utilizing easy-to-collect nasal swabs, but demonstrated less than 100% PPA compared to PCR..

Antigen-Based Testing but Not Real-Time Polymerase Chain Reaction Correlates With Severe Acute Respiratory Syndrome Coronavirus 2 Viral Culture

“…Of the 38 rt-PCR–positive results utilized for these analyses, 9 were antigen test negative. These 9 negative results showed a trend toward longer time from symptom onset compared to the 29 rt-PCR assay–positive/antigen test–positive specimens (average, 4.4 vs 2.9 days, P = .108) [ 16 ]. Of the 9 samples that were rt-PCR positive/antigen test negative, the viral RNA copy number was significantly lower than that observed for the 29 rt-PCR–positive/antigen test–positive specimens (mean, 4.3 vs 7.0 log 10 copies/mL, P < .001; Supplementary Figure 1 ).…”

“…Prospective specimen collection, specimen use, and participant demographics for the parent study were described previously [ 16 ]. This study involved the use of residual respiratory swab specimens from the previous antigen test FDA EUA study, which occurred across 21 geographically diverse study sites, from 5 to 11 June 2020.…”

“…Antigen test positivity and SARS-CoV-2 TMPRSS2 culture positivity (an indicator of the presence of infectious virus), with rt-PCR confirmation, were fit with a probit model as a function of viral load, using results from the Veritor EUA study [ 16 ]; rt-PCR assay Ct scores were used to estimate viral RNA loads, as described above. SARS-CoV-2 VeroE6 culture positivity linkage to viral load was inserted into the probit model for probability of a positive result using data from Huang et al [ 17 ].…”

“…Several lines of indirect evidence suggest that antigen-based testing may align better with virus culture–based test results compared to rt-PCR. For example, higher rt-PCR cycle threshold (Ct) values from specimens are observed when individuals are negative by antigen testing or virus culture–based testing compared to those from individuals who are antigen test–based [ 16 ] or culture test–based positive [ 17 ]. In addition, current EUA SARS-CoV-2 antigen tests have optimal performance profiles [ 12–15 ] at time points that overlap with the expression profile of SARS-CoV-2 subgenomic RNAs, which are markers of replicating virus [ 8 ].…”

Evaluation of the rapid antigen test Panbio COVID-19 in saliva and nasal swabs in a population-based point-of-care study

“…Ag-RDT directly identify SARS-CoV-2 proteins produced by replicating virus in respiratory secretions [3]. In contrast to the reference nucleic acid amplification tests (NAAT), such as rRT-PCR, the Ag-RDT are relatively inexpensive, simple to perform, do not require infrastructure, and enable obtaining point-of-care results within a few minutes [4].…”