Antibody testing just went DIY: The FDA has given the go-ahead to a COVID-19 test that can detect the virus’s antibodies in a dried blood spot sample taken at home and mailed to a lab.
The COVID-19 Self-Collected Antibody Test System, developed by Symbiotica Inc., is the first home-collected antibody test to receive the FDA’s emergency use authorization, though 75 other antibody tests have been approved for use on samples collected in point-of-care settings.
Once the test is prescribed, fingerstick blood samples can be taken from individuals as young as 5 years old (with help from an adult for anyone under the age of 18). The sample will be processed for evidence of COVID-19 antibodies at one of Symbiotica’s labs.
Symbiotica is a California-based clinical laboratory that both develops and processes a variety of at-home assays. Besides the antibody test, other tests in the company's portfolio detect active COVID infections, diseases like rheumatoid arthritis, celiac disease and lupus, and a variety of food and environmental allergies.
The presence of antibodies in a person’s blood points to a past COVID infection, but scientists still aren’t sure how long antibodies can stay in the bloodstream—and therefore how recent the infection was—nor whether the person is at risk for repeat infections.
“The authorization of the first prescription-use, home-collection antibody test will play an important role in helping healthcare professionals identify individuals who have developed an adaptive immune response from a recent or prior COVID-19 infection,” Jeff Shuren, M.D., director of the FDA’s Center for Devices and Radiological Health, said in a release. “The FDA will continue to authorize COVID-19 tests that will give more Americans access to greater testing flexibility and options.”
Though the antibody test can’t diagnose a current case of COVID, the FDA has recently authorized a handful of other self-collected tests that can. So far, more than 40 COVID tests that use samples taken at home have been OK’d, including a mix of eight prescription and over-the-counter molecular and antigen tests that can also be processed in the home, rather than being sent to a lab.
Most recently, in early March, the FDA granted an emergency use authorization to the first at-home molecular test that can be taken and processed without a prescription. That kit, from Cue Health, includes a cartridge that analyzes nasal swab specimens for genetic material linked to the virus (instead of the proteins studied in an antigen test). Results are available in about 20 minutes via an accompanying mobile app.