U.S. FDA Issues Guidance for Test Developers Addressing Coronavirus Variants

The U.S. Food and Drug Administration (FDA) announced guidance on February 22, 2021, for medical product developers to address the emergence and potential future emergence of variants of SARS-CoV-2, the beta coronavirus that causes COVID-19.

The new Policy for Evaluating Impact of Viral Mutations on COVID-19 Tests provides information on evaluating the potential impact of emerging and future viral genetic mutations, which may be the basis of viral variants, on COVID-19 tests, including design considerations and ongoing monitoring. The FDA has already issued a safety alert to caution that the presence of viral genetic mutations in a patient sample can potentially change the performance of a diagnostic test.

The FDA identified a few tests that are known to be impacted by emerging viral mutations, though at this time, the impact does not appear to be significant.

The clinical impact of viral genetic mutations on a test’s performance is influenced by various factors, such as the variant sequence, the design of tests. For example, molecular tests designed to detect multiple SARS-CoV-2 genetic targets are less susceptible to the effects of genetic variation than tests designed to detect a single genetic target.

The guidance describes the FDA’s activities to understand better the public health impact of new virus variants and the impact on test performance, such as monitoring publicly available genomic databases for emerging SARS-CoV-2 genetic mutations and monitoring the potential effects of genetic variation on molecular tests that have been issued a EUA.

The guidance also provides recommendations to test developers, such as considering the potential for future viral genetic mutations when designing their test and conducting their own routine monitoring to evaluate the potential impact of new and emerging viral genetic mutations, which may be the basis of viral variants, on the performance for molecular, antigen and serology SARS-CoV-2 tests.

The FDA is an agency within the U.S. Department of Health and Human Services.