The FDA released a list of emergency use authorized COVID-19 antibodies to offer comparisons over the sensitivity of the diagnostics.
Among the larger companies on the list with larger sample sizes, antibody tests made by Roche and Siemens were some of the highest-ranking diagnostics, according to the FDA comparison.
Tests are in part described by positive and negative predictive values (PPV and NPV), using a test’s sensitivity and specificity along with an assumption about the percentage of individuals within the population who have antibodies for SARS-CoV-2, the virus causing COVID-19.
Roche’s Elecsys Anti-SARS-CoV-2 pan-Ig antibody test produced specificity of 99.8% in more than 5,200 samples, producing a 100% NPV with an antibody prevalence of 5%. The company’s Elecsys Anti-SARS-CoV-2 S, a more recent version, produced 100% specificity in nearly 6,000 samples, marking an NPV of 98.8% with the 5% prevalence.
Siemens’ ADVIA Centaur SARS-CoV-2 IgG, which was sampled the most of its antibody tests (1,831 subjects) had 99.9% specificity and 100% NPV at a 5% prevalence. All of Siemens’ antibody tests produced specificity of better than 99%.
Abbott’s AdviseDx SARS-CoV-2 IgM (Alinity i), which detects a different antibody than the ones produced by Roche and Siemens, produced a 99.6% specificity and 99.7% NPV in nearly 3,000 samples.
The company’s Architect SARS-CoV-2 IgG registered 99.6% specificity and 100% NPV at 5% prevalence in just over 1,000 samples, as well. However, while the antibody tests from Roche and Siemens offered PPV values close to 100%, Abbott’s tests PPVs were in the low 90s, while its Alinity i SARS-CoV-2 IgG dipped as low as 84% for PPV (in 100 samples).
Other companies produced numbers that matched or bettered those put forth by Roche, Siemens and Abbott, but in far less samples.