Quidel Receives Amended EUA for Rapid Antigen COVID-19 Diagnostic Assay Using Sofia 1 Instrument

Quidel Corporation (San Diego, CA, USA) has received an amended Emergency Use Authorization (EUA) from the US FDA, allowing the company to run its Sofia SARS Antigen FIA on its first generation Sofia Fluorescent Immunoassay Analyzer (Sofia 1).

The Sofia SARS Antigen FIA is to be used as an aid in the rapid detection of SARS-CoV-2 in nasal or nasopharyngeal specimens from patients meeting the Centers for Disease Control and Prevention’s (CDC) criteria for suspected COVID-19 infection. The assay is currently available for sale in the US States under EUA, and Quidel is now shipping the product to its customers.


Quidel has previously received EUA to run the Sofia SARS Antigen FIA, a rapid point-of-care test for COVID-19, on the second-generation Sofia 2 instrumented system. Sofia 1 provides an accurate, objective and automated result in 15 minutes. Like the Sofia 2, the original Sofia 1 instrument offers two distinct workflows. Depending upon the user’s choice, the Sofia SARS Antigen FIA cartridge is placed inside the instrument for automatically timed development (WALK AWAY Mode); or test cartridges can be placed on the counter or bench top for a manually timed development and then placed into the instrument to be scanned (READ NOW Mode), allowing the user to markedly increase testing throughput per hour. There are approximately 20,000 Sofia 1 instruments installed in hospitals and physician offices worldwide.

“This EUA amendment permits our novel Sofia SARS Antigen test to be used on both models of our Sofia instruments, leveraging our worldwide installed base of over 43,000 combined placements, allowing many of our larger healthcare facilities to be able to quickly diagnose first responders, healthcare workers, and other high priority personnel,” said Douglas Bryant, president and chief executive officer of Quidel Corporation. “The demand for the Sofia SARS Antigen test kits and Sofia instruments has been phenomenal. In under 10 days, we had over 1,000 sites on contract and continue to expect that we will ship every cartridge that we can manufacture for the foreseeable future.”

Additionally, the Biomedical Advanced Research and Development Authority {(BARDA) Washington, DC, USA} has awarded funding to Quidel for the development of its SARS-CoV-2 test. BARDA, a division of the Office of the Assistant Secretary for Preparedness and Response (ASPR) within the US Department of Health and Human Services (HHS), has awarded USD 634,643 to Quidel for the development of a four-analyte antigen test on the company’s Sofia 2 instrumented system. Quidel will develop the test to detect SARS-CoV-2, respiratory syncytial virus, influenza A, and influenza B. According to BARDA, the sample-to-answer, point-of-care assay is being developed to be CLIA waived, enabling possible use in doctors’ offices and to be sensitive enough for the early detection of SARS-CoV-2 in samples from people who have COVID-19 symptoms.