FDA Approves First Antibody Test For Coronavirus

The Food and Drug Administration approved a test that detects coronavirus antibodies in the blood on Thursday.

The test, called a serology test, can identify whether someone has already had an infection and might have immunity, and is less effective in identifying active infections. 

However, a positive result on this test does not guarantee immunity, as it tests for the presence and not the efficacy of antibodies. The strength of immune responses can vary depending on the person.

Other coronavirus tests work differently. They start by swabbing a patient’s nose or throat, then find and replicate virus genetic material in the swab through a process called “reverse transcription-polymerase chain reaction” (RT-PCR).

But the serology test by Cellex Inc. looks for antibodies called immunoglobulin M and immunoglobulin G in a finger prick of blood. The test takes about 15 minutes to get results. RT-PCR tests can take hours to days.

The FDA told Cellex Inc. in a letter that “circumstances exist justifying the authorization of emergency use of in vitro diagnostics for the detection and/or diagnosis of [coronavirus].”