US-based Quanterix has secured emergency use authorisation (EUA) from the US Food and Drug Administration (FDA) for its Simoa Semi-Quantitative SARS-CoV-2 IgG antibody test.

The test is designed to run on the Simoa HD-X Analyzer, a fully automated high-throughput immunoassay instrument that detects and quantitates IgG antibodies to SARS-CoV-2 in serum or EDTA plasma.

The Simoa (single molecule array technology) is a digital approach for immunoassays that enables single molecules to be counted for protein biomarker research applications.

The new test targets the antibodies that are directed against the region of the novel coronavirus known as the spike protein, which contains multiple subunits.

These subunits together mediate entry of the virus into the human cells, and for this the authorised COVID-19 vaccines are being designed to elicit an antibody response to spike protein.

The new Simoa Semi-Quantitative SARS-CoV-2 antibody test is expected to help in measuring the antibody response to vaccine therapy.

Quanterix said that the assay may also be utilised to measure IgG antibodies in patients who are suspected with previous infection or recent SARS-CoV-2 exposure.

This new antibody test provides a numerical result which represents the concentration of antibodies from 0.21 to 250 μg/mL.

Quanterix chairman, CEO and president and Powering Precision Health (PPH) founder Kevin Hrusovsky said: “There is an apparent need for precise, accurate and reliable testing at each stage of this global pandemic including measuring serological response to vaccines.

“With our deep understanding of precision medicine and digital biomarker technology we are committed to supporting the full study of COVID-19 immunology including the ability to measure the level of a person’s infection or vaccine-induced immune response as well as to support the development of convalescent plasma therapies.”

In June last year, Quanterix has entered into a definitive agreement to acquire Swedish firm UmanDiagnostics in a deal valued at around $22.5m.