The US Food and Drug Administration (FDA) granted De Novo clearance to QuidelOrtho Corp to market its new Sofia 2 SARS Antigen+ FIA, a rapid antigen test that detects COVID-19.

The company was the first to receive FDA emergency use authorization for its Sofia 2 SARS Antigen FIA test in May 2020. The Sofia 2 SARS Antigen+ FIA, intended for prescription use and point-of-care settings only, is designed to aid in the diagnosis of SARS-CoV-2 infections in symptomatic individuals when tested at least twice over three days with at least 48 hours between tests and within six days of symptom onset. 

“As the first company to introduce a rapid antigen test for COVID-19 when the FDA granted emergency use authorization for the Sofia SARS Antigen FIA in May of 2020, we are pleased to again be the first to receive De Novo FDA clearance for our Sofia 2 SARS Antigen+ FIA,” says Douglas Bryant, president and CEO of QuidelOrtho Corp, in a press release. “With this De Novo authorization, Sofia becomes the predicate device upon which subsequent devices of the same type and intended use will be compared. This designation is a tribute to the incredible ingenuity, commitment to quality, and cohesion of our entire QuidelOrtho team from R&D and regulatory affairs to design, manufacturing, labeling, and packaging.”

According to the company, the test—a lateral flow immunofluorescent assay that is used with the Sofia 2 fluorescent immunoassay analyzer—provides automated results in 10 minutes, a 33% reduction from the 15-minute processing time achieved in the first iterations of the Sofia SARS Antigen FIA assay. The Sofia 2 system also comes connected to Virena, QuidelOrtho’s data management system, which provides aggregated, de-identified testing and surveillance data in near real-time.

The enhanced Sofia 2 SARS Antigen+ FIA test kit includes other upgraded features, such as prefilled reagent vials, improved ergonomic sample extraction, and a dropper design for easy dispensing of patient samples into the test cassette sample well. 

Results are for the identification of the SARS-CoV-2 nucleocapsid protein antigen, which is generally detectable in upper respiratory specimens during the acute phase of infection. Positive results indicate the presence of viral antigens of SARS-CoV-2, but clinical correlation with patient history and other diagnostic information is necessary to determine infection status. Positive results do not rule out bacterial infection or co-infection with other viruses, as the agent detected may not be the definite cause of disease.

A negative test is presumptive, and it is recommended these results be confirmed by a molecular SARS-CoV-2 assay. Negative results do not preclude SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions.

“Today’s marketing authorization of the first COVID-19 antigen test underscores our ongoing commitment to maintain access to testing long-term,” says Jeff Shuren, MD, director of the FDA’s Center for Devices and Radiological Health, in a March 10 press release. “We look forward to working with developers of all test types who are interested in moving their products through our traditional review pathways and encourage those who are ready to do so as soon as possible.”

Along with this De Novo authorization, the FDA is establishing criteria called special controls that define certain requirements, including required labeling and performance testing. When met, the special controls, in combination with general controls, provide a reasonable assurance of safety and effectiveness for tests of this type. 

This action also creates a new, Class II regulatory classification for simple devices to directly detect SARS-CoV-2 viral targets from clinical specimens in point-of-care settings or at-home use, which means that subsequent devices of the same type with the same intended use may go through the FDA’s 510(k) pathway, whereby devices can obtain clearance by demonstrating substantial equivalence to a predicate device.