Weeks after launching their own COVID-19 molecular testing initiatives, lab giants Quest Diagnostics and LabCorp have begun offering antibody tests nationwide for the next phase of the coronavirus pandemic.
Quest is now allowing individuals to order the immune response test for themselves online through the company’s direct-to-consumer portal. Previously, its antibody test service was made available for healthcare providers to order on behalf of their patients. After requesting and purchasing the test, people can set an appointment for a blood draw at one of Quest’s service centers.
Meanwhile, LabCorp will administer its blood tests through its service center network in addition to doctors' offices and the company’s specimen collection locations at participating Walgreens pharmacies.
LabCorp said it has been offering limited antibody testing to healthcare professionals since late March and currently can perform over 50,000 tests per day. It plans to expand that capacity to 200,000 per day by the middle of next month. Both LabCorp and Quest said they expect to turn around results within a few days.
Neither company’s test has yet received an official authorization from the FDA, but the agency is allowing antibody test developers to proceed without review with a few caveats. The tests’ accuracy must be validated by the company, and they cannot be used to diagnose a COVID-19 infection.
In addition, both LabCorp and Quest stated that a positive serological test result alone is not enough to confirm that a person is immune to the novel coronavirus. It is not known what antibody levels will provide protection from infection, or for how long, but these test results can still provide information on how far the disease has spread.
"While the science on COVID-19 is evolving, testing for antibodies may identify people who have likely been exposed to COVID-19 and might have mounted an immune response to the virus,” Quest’s chief medical officer, Jay Wohlgemuth, said in a statement. “Our goal is to empower individuals and their physicians to make informed decisions about their risk of infection and of spreading the virus."
Members of Congress recently called on the FDA to reevaluate its relaxed stance toward COVID-19 antibody testing and urged the agency to clamp down on unauthorized tests, some of which promise to allow people to return to work safely.
However, the accuracy of many antibody tests on the market has been called into question, including by a group of Oxford University researchers. Meanwhile, the FDA has teamed up with the Centers for Disease Control and Prevention and the National Institutes of Health to validate antibody tests voluntarily submitted by companies for review, with the first results previously expected in the coming week.