FDA Breaks New Ground by Authorizing SARS-CoV-2 Tests for Sample Pooling

It’s not uncommon for the FDA to revise the Emergency Use Authorization (EUA) for a particular diagnostics test to permit a new clinical use. In most cases, these expansions don’t even get an official announcement. But on July 18, the agency saw fit to pull out all of the stops and officially announce an EUA that was both unprecedented and significant because it allowed for COVID-19 testing on pooled samples. The Quest SARS-CoV-2 Test The distinction of being the first test approved for pooled testing went to Quest Diagnostics’ SARS-CoV-2 RNA test, which initially received EUA back in March. The expanded EUA allows the test to be used with pooled upper respiratory specimens in sample pools comprised of four individuals. “The new update allows Quest to test 3,600 more tests per day,” noted Timothy Stenzel, director of the Office of In Vitro Diagnostics and Radiological Health at the FDA’s Center for Devices and Radiological Health during a recent agency “town hall” briefing, “and if you add pooling on top of that. . . they can substantially increase the throughput.” Use of pooling takes on particular significance during the current COVID-19 testing supplies shortage because it enables testing labs to get the most out of their limited testing resources. But there’s also a tradeoff. Pooling dilutes the nucleic acids produced by the SARS-CoV-2 virus, thereby creating the risk of false negatives. To secure the EUA expansion for the SARS-CoV-2 RNA test, Quest provided the FDA clinical data showing that none of a total 3,091 specimens from a population with a prevalence rate of 1 to 10 percent would have come back falsely negative had the specimens been pooled. Quest immediately began performing pooled sampling testing with the assay starting with its laboratories in Marlborough, MA, and Chantilly, VA. Takeaway Less than a week later, the FDA announced that LabCorp’s COVID-19 RT-PCR Test had received the second expanded EUA for pooled SARS-CoV-2 testing. The LabCorp test is authorized for human specimen collection at home using the Pixel by LabCorp or other home sample collection kits authorized for use with LabCorp’s test, or by a healthcare provider. However, only samples collected by healthcare providers may be pooled using the test, the FDA noted. The expanded EUA also allows the test to be used for testing the broad population under the FDA’s new asymptomatic screening guidance, making it the first SARS-CoV-2 test to gain that distinction. As of August 13, a total of four COVID-19 tests have received EUA for sample pooling.   COVID-19 Tests Receiving EUA Authorization for Sample Pooling

EUA Date	Manufacturer	Product
July 18	Quest Diagnostics	SARS-CoV-2 RNA test EUA expanded for pool sampling use
July 24	LabCorp	EUA for COVID-19 RT-PCR test and home collection kit reissued for sample pooling and use on asymptomatic patients
July 31	University of California San Diego Health	UCSD RC SARS-CoV-2 Assay gets EUA for sample pooling
Aug. 3	Poplar Healthcare	Poplar SARS-CoV-2 TMA Pooling assay gets EUA for sample pooling