FDA Authorizes First Emergency COVID-19 Antigen Test

The US Food and Drug Administration (FDA) has issued the first emergency use authorization (EUA) for an antigen diagnostic test that can detect coronavirus 2019 (COVID-19).

The new authorization was granted to Sofia 2 SARS Antigen FIA, from Quidel Corporation, granting the test for use in high and moderate complexity laboratories certified by Clinical Laboratory Improvement Amendments, as well as by CLIA Certificate of Waiver-operating facilities for point-of-care testing.

The opening of this new category of COVID-19 testing makes antigen the third type authorized by the FDA, following polymerase chain reaction (PCR) tests that detect genetic virus material in positive patients, and serological tests that can identify individuals who have developed an adaptive immune response to the virus due to a current or prior infection.

An antigen diagnostic test gives clinicians the benefit of a rapid, specific virus detection in just minutes, FDA commissioner Stephen Hahn, MD, said in a statement.

“Antigen tests are very specific for the virus, but are not as sensitive as molecular PCR tests,” he said. “This means that positive results from antigen tests are highly accurate, but there is a higher chance of false negatives, so negative results do not rule out infection.”

With that limitation in mind, Hahn emphasized the need for negative antigen test results to be confirmed with a PCR test prior to treatment decision-making.

Antigen tests are additionally produced at lower costs than PCR tests, and could eventually result in millions of US individual tests daily once multiple options are authorized for the option. Hahn anticipated more antigen tests to follow EUA approval.

“We also anticipate providing an EUA template for antigen tests, similar to ones we’ve released for other test types, to help manufacturers streamline submissions and help expedite our review and issuance of additional EUAs,” he said.