FDA Grants Emergency Use Authorization for Pooled Sample Testing for COVID-19

The FDA reissued an emergency use authorization (EUA) for the Quest Diagnostics SARS-CoV-2 rRT-PCR test for COVID-19 diagnostic use with pooled samples containing up to four individual swab specimens, making it first test to be authorized for this use.

The Quest test was initially authorized on March 17, 2020, to test individual samples for suspected COVID-19 infection. The test is still authorized for use with individual nasal swab specimens that are self-collected at home or in a health care setting.

The additional authorization was granted based on clinical data presented by Quest Diagnostics to the FDA, in which none of 3,091 total specimens, if pooled, would have been incorrectly determined to be negative for COVID-19.

Sample pooling works by collecting individual specimens that are combined into small batches, or pools, by the laboratory and using one test for the batch rather than running individual tests on each sample. A negative result means that all patients in the pool are considered negative. If a positive result occurs, each specimen is retested individually. This method uses fewer testing supplies and can get results to patients more quickly since more tests are being run at once. The pooling strategy is most effective in regions with low prevalence of infection.

With the new EUA, the Quest test may be used with pooled upper respiratory specimens (nasopharyngeal, mid-turbinate, anterior nares, or oropharyngeal swabs), with up to four individual samples per batch.

Sources: FDA press release, July 18, 2020; Quest Diagnostics press release, July 18, 2020.