NEW YORK – The US Food and Drug Administration issued new guidance on Tuesday for molecular diagnostic tests for influenza and respiratory syncytial virus, allowing developers to modify already-cleared tests in certain ways to make flu and RSV tests more widely available while also preserving reagents for SARS-CoV-2 testing.
The FDA said 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 new guidance specifically advises developers that tests previously indicated for use with samples collected in viral transport media can 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.
The agency will also not object to tests modified to add healthcare provider-collected anterior nares or mid-turbinate specimens, so long as the test is already cleared for use with nasopharyngeal swab samples.
The agency called out specific modifications in the guidance document that it believes would create undue risk. These include adding a transport media other than the ones it identified, adding any other sample type, or adding indications for use with self-collected specimens, over-the-counter use, or in a new patient population relative to the indication in the original FDA-cleared test.
Manufacturers must provide labeling information to help users understand any modifications that have been made, and they must verify and validate test performance.
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 agency said.