The Food and Drug Administration (FDA) has issued an Emergency Use Authorization (EUA) for Quanterix’s Simoa Semi-Quantitative SARS-CoV-2 IgG Antibody Test, which can be operated on a fully automated high-throughput immunoassay instrument called Simoa HD-X Analyzer.

The test checks for antibodies that are directed against the spike protein, a region of the novel coronavirus.

The spike protein has multiple subunits that facilitate the virus entry into human cells.

Quanterix noted that many candidates and authorised Covid-19 vaccines are designed to elicit an antibody response to viral spike protein.

The Simoa Semi-Quantitative SARS-CoV-2 test may, thus, be used to assess the antibody response to vaccine therapy.

In addition, it can be used to measure IgG antibodies in patients suspected of prior infection or those that have lately been exposed to SARS-CoV-2.

The test delivers a numerical result showing antibody concentration ranging from 0.21 to 250mg/mL.

Data from clinical studies showed that the test had a 100% positive per cent agreement (sensitivity) and 99.2% negative per cent agreement (specificity), 15 days or more after a positive PCR test.

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.

“This EUA underscores our longstanding science-first mentality and deep dedication to the highest standards of quality and scientific rigour across our business.”

A digital approach to immunoassays, single molecule array technology (Simoa) aids in counting single molecules for protein biomarker research purposes.

It is presently used in various therapeutic areas such as oncology, neurology, cardiology, inflammation and infectious disease.

In 2019, Quanterix signed a definitive agreement to acquire Swedish neurofilament light (NF-L) antibody supplier UmanDiagnostics in a deal valued at $22.5m.