NEW YORK — US Food and Drug Administration officials said Wednesday monkeypox virus assays should target multiple genetic sequences to reduce the risk that variants will escape detection.
Kristian Roth, deputy director of the division of microbiology devices at the FDA, said during a virtual town hall meeting with diagnostics developers and other industry stakeholders that the US Centers for Disease Control and Prevention recently reported observing gene deletions among some monkeypox isolates collected in California, and those deletions affect the previously published primer and probe sequences some organizations had been using to develop their monkeypox tests.
The agency recommends that any assay improve its performance with potential variants by targeting at least one segment of genetic code that is not specific to a monkeypox virus variant or including a non-variola orthopoxvirus target as part of a multiple-target test, Roth said. He said two to four targets would likely provide both efficiency and resilience to mutation.
The agency will review single-target tests, agency officials said, but companies that create those tests are taking a risk whereas including at least a monkeypox target and a non-variola orthopoxvirus target is a better strategy, Roth said.
During a virtual town hall held last month, FDA officials described plans for an Emergency Use Authorization fast lane for assay makers who signal to the agency by Oct. 13 that they are working on monkeypox tests.