Agency Temporarily Allows Modifications of Influenza and RSV Tests Without Premarket Notification

On Oct. 13, the U.S. Food and Drug Administration issued new guidance on molecular diagnostic tests for influenza and respiratory syncytial virus (RSV). The upshot of the guidance is to temporarily allow makers of flu and RSV tests that the agency has already cleared to make certain modifications to those products without submitting 510(k) premarket notification in the interests of making the tests more widely available while also not using up reagents needed for SARS-CoV-2 testing.

There is significant overlap in warning signs and symptoms between SARS-CoV-2 and other
respiratory viral infections, including influenza and RSV, the guidance explains. “Increased availability of molecular influenza tests during the COVID-19 pandemic is important due to the similarity in symptoms between COVID-19 and the seasonal influenza.” The guidance also notes that because of this overlap in symptoms, molecular influenza tests are often offered as part of a panel of tests including RSV.

Diagnostic tests for SARS-CoV-2 and other respiratory viral infections generally use many of the same components. For example, the same specimen collection devices and transport media required to perform many FDA-cleared molecular influenza tests are also needed for most molecular diagnostic SARS-CoV-2 assays. And, of course, those devices and media are currently in short supply.
Accordingly, the guidance states that for the duration of the COVID-19 public health emergency, the agency “does not intend to object” to the addition of certain transport media types and sample types for previously FDA-cleared molecular flu and RSV tests. Such modifications will not require submission of a 510(k) premarket notification so long as they do not “create undue risk in the light of the public health emergency.” The policy does not apply to tests and devices for other viruses, antigen-based tests, multiplex respiratory panels, or multiplex molecular tests that include SARS-CoV-2 targets, the guidance specifies.

Modifications Not Requiring Premarket Notification

Specifically, tests previously indicated for use with samples collected in viral transport media may now be modified to use samples collected in sterile phosphate buffered saline, “including molecular grade PBS and other similar formulations such as Dulbecco’s PBS,” as well as into sterile normal saline. Also on the agency’s “does-not-intend-to-object” list are modifications to add healthcare provider-collected anterior nares or mid-turbinate specimens, provided that the test is already cleared for use with nasopharyngeal swab samples.

Modifications Still Requiring Premarket Notification

The guidance also cites specific modifications that the agency believes would create undue risk and thus not subject to the temporary relaxation of premarket notification requirements, including:

• Adding a sample type not identified in the examples cited as not creating undue risk to an FDA-cleared molecular influenza and RSV test;
• Adding an indication for use with self-collected specimens to an FDA-cleared molecular influenza and RSV test;
• Adding a transport media not identified in the not-creating-undue risk examples to an FDA-cleared molecular influenza and RSV test; or
• Adding an over-the-counter (OTC) use or new patient population (e.g., pediatrics) to the indication for an FDA-cleared molecular influenza and RSV test.

The guidance also instructs developers to provide labeling information to help users understand whatever modifications have been made and to verify and validate performance of the modified test.

Here are the key new FDA EUAs and clearances announced during the month of October:

New FDA Emergency Use Authorizations (EUAs) & Approvals