Benzinga | Jan 11, 2021 04:31PM EST

Quanterix Receives FDA Emergency Use Authorization For SARS-CoV-2 N Protein Antigen Test

Antigen test available on Simoa HD-X Analyzer(r) intended for qualitative detection of the nucleocapsid protein (N protein) from SARS-CoV-2 in nasopharyngeal swab specimens

Full suite of Research Use Only Assays Also Available for SARS-CoV-2 Acute and Long Hauler Surveillance and Profiling Studies

Quanterix Corporation (NASDAQ:QTRX), a company digitizing biomarker analysis to advance the science of precision health, today announced that the Food and Drug Administration (FDA) has issued an Emergency Use Authorization (EUA) for its Simoa(r) SARS-CoV-2 N Protein Antigen Test that can be run on the Simoa HD-X Analyzer(r), a fully automated high-throughput immunoassay instrument.

The Simoa SARS-CoV-2 N Protein Antigen Test detects the presence of the SARS-CoV-2 virus nucleocapsid protein (or N protein) which is known to be elevated in respiratory fluids during the initial acute phase of the infection. Direct detection of antigen proteins from the virus may be a more meaningful measure of infection status than detection of RNA by rRT-PCR because genetic material can linger even after the virus has left the body, resulting in increased risk of false positives1. In clinical studies, the test demonstrated a sensitivity of 97.7% (positive percent agreement) and specificity of 100% (negative percent agreement) up to 14 days following onset of symptoms.

Under the current EUA, the SARS-CoV-2 N Protein Antigen Test is intended for use with nasopharyngeal (NP) samples in individuals suspected of COVID-19 by their healthcare providers. Quanterix will be pursuing authorization for additional sample types, including nasal swabs, saliva, and capillary dried blood obtained from a fingerstick. Preliminary clinical research studies suggest the viral antigen may be readily detectable in asymptomatic and pre-symptomatic patients, and Quanterix is exploring extending the test to screening applications, home-based sample collection and pooling to enable larger scale testing.

FDA authorization of the Simoa SARS-CoV-2 N Protein Antigen Test for NP samples is an important early step in a project funded by the NIH Rapid Acceleration of Diagnostics (RADx) initiative to apply Simoa digital biomarker technology to decentralized SARS-CoV-2 antigen detection in non-invasive sample types. An ultimate aim of this NIH program is to improve clinical laboratory tests that will increase the capacity of SARS-CoV-2 testing in the U.S.

"As case counts and positivity rates rise globally, the COVID-19 testing landscape is of critical importance," said Kevin Hrusovsky, Chairman, Chief Executive Officer and President, Quanterix and Founder, Powering Precision Health (PPH). "Antigen viral levels, if precisely tested, are potentially a better measure of active infection, and for understanding the kinetics and distribution of viral load across different sample types over the duration of the infection, treatment and recovery. We are pleased to announce a test that not only provides high levels of sensitivity and specificity, but is economical, well suited for high throughput testing and utilizes a complementary supply chain helping efforts to scale testing."

Simoa RUO assays for COVID-19 Research

Quanterix offers a family of assays tailored to RUO applications. In addition to its EUA assay, Quanterix today also announced the release of the SARS-CoV-2 N Protein Antigen Advantage Assay, tailored for Research Use. This quantitative ultra-sensitive assay is directed to research applications in sample matrices including NP swabs, nasal swabs, serum, plasma, capillary dried blood, and saliva. The assay complements the quantitative Simoa SARS-CoV-2 IgG antibody assay recently introduced for the HD-X instrument which enables researchers to measure both the virus and immune response from the same samples including blood obtained by minimally invasive fingerstick collection.

"In addition to direct viral antigen and antibody detection capabilities, researchers around the world require the most sensitive and specific assays for both immune monitoring and disease profiling applications," said Hrusovsky. "Our expanded RUO portfolio of ultrasensitive assays also includes customizable panels of up to 10 critical biomarkers for cytokine and chemokine profiling and for carefully monitoring cytokine storms. Our team is working diligently to facilitate research being done on patients with non-resolving immune responses (or COVID-19 long haulers), as well as those with associated vascular and neurological effects. Blood-based biomarkers including antigen, IgG, Nf-L, GFAP, in addition to angiogenesis panels can accurately quantify viral load, immune response, organ damage and level of inflammation from minimally invasive samples at ultra-sensitive levels."