The U.S. Food and Drug Administration (FDA) granted an emergency use authorization (EUA) to LabCorp, permitting diagnostic testing of groups of individuals for active COVID-19 infections utilizing matrixed pooled testing, a method that tests several patient samples at once, both the FDA and LabCorp announced in separate press releases.
The FDA said the EUA also allows LabCorp to test people who do not have symptoms or who have no reason to suspect COVID-19 infection. The “authorization eliminates the need for a provider to consider risk factors such as exposure or community spread when prescribing this test. The FDA continues to work with test developers to expand access to COVID-19 testing,” the FDA said.
The reissued EUA is for LabCorp’s molecular test for the detection of nucleic acid from SARS-CoV-2, which originally received an EUA from the FDA earlier this year.
LabCorp’s matrixed pooled strategy for COVID-19 provides a testing approach for populations by allowing for larger groups of samples to be tested at one time. LabCorp’s matrixed pooled testing method involves testing up to five samples at once. If there is a positive sample in the pool, LabCorp can identify the individual positive sample in the pool using patterns detected by its robotic testing platform, the company contends.
However, LabCorp also cautioned that negative results from pooled testing should not be treated as definitive. If a patient’s clinical signs and symptoms are inconsistent with a negative result or results are necessary for patient management, the patient should be considered for individual testing. Specimens included in pools where the positive sample cannot be identified using the matrix must be tested individually prior to reporting a result, LabCorp said.
Pooled testing can reduce the number of tests required in specific populations, optimize laboratory testing supplies, and increase testing capacity. Pooled testing works best in areas with a low prevalence of SARS-CoV-2 infections, meaning most results are expected to be negative.
Another concern with pooled testing is that it may make it more difficult to detect positive results, since pooling in the laboratory dilutes any viral material present in the samples.
The FDA’s EUA granted to LabCorp for its approach to pooled testing follows the agency’s decision to issue a similar EUA to Quest, allowing it to use pooled sampling for its rRT-PCR test.
