FDA Requires Review of COVID-19 Antibody Tests
May 8, 2020
To ensure the accuracy of COVID-19 antibody tests and guard against fraudulent testing claims, the FDA recently announced that it would update its March 16, 2020 guidance and start requiring serology test developers to obtain an Emergency Use Authorization (EUA). The agency has also outlined test performance expectations. Manufacturers that have already commercialized product based on validation testing under the FDA’s March 16 guidance have 10 days from publication of the new guidance to submit an EUA application. For new tests, yet to be validated, the manufacturer has 15 days from the point of validation to request their EUA. Test manufacturers and laboratories will use different templates to request FDA authorization. The EUA serology template for manufacturers can be found here. The EUA serology template for laboratories can be found here. Updated FAQs from the FDA on COVID-diagnostics tests can be found here.
The University of Utah’s ARUP Laboratories has validated an antibody test and manufacturers Quansys Bioscience and Predictive Laboratories have also validated their serology tests and are respectively seeking an EUA. Another manufacturer with ties to Utah, Becton Dickinson, has a validated antibody test and is seeking their EUA. D has a large presence in Utah, but produces the test outside the state. Cibus Biotechnologies and Medsentials are in the process of validating an antibody test and will be seeking an EUA.
Under the previous March 16 guidance for serology testing, the FDA had said it would allow makers of antibody tests to validate their tests before marketing and bypass the EUA process. The intent was to speed up development of these serological tests to detect the extent of COVID-19 immunity in communities.
There are two types of antibody tests. A lateral flow test is a rapid point of care test much like a pregnancy test. A serum test requires laboratory analysis of the blood sample to determine outcomes. The serum test typically is more robust while the lateral flow test is a qualitative test indicating yes or no for the type of antibodies being tested. There are two types of antibodies. The IgG antibodies indicate longer term immunity since these antibodies develop later after exposure to the virus. Tests that detect IgM antibodies indicate more short-term exposure since they present early after infection and are only present in the bloodstream for a shorter period of time.
Despite FDA’s increased oversight, many experts believe that COVID-19 antibody testing may still face limitations as a predictor of immunity until we more fully understand how the virus works.