Today, the U.S. Food and Drug Administration authorized marketing of a diagnostic test to detect Zika virus immunoglobulin (IgM) antibodies in human blood.

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The ZIKV Detect 2.0 IgM Capture ELISA is the first Zika diagnostic test the FDA has allowed to be marketed in the U.S.; previously, tests for detecting Zika virus IgM antibodies—including the ZIKV Detect 2.0 IgM Capture ELISA—had been authorized only for emergency use under the FDA’s Emergency Use Authorization (EUA) authority.

“At the onset of the Zika virus outbreak, when little was known about the disease or how to diagnose it, the FDA worked quickly with manufacturers to encourage the development of diagnostic tests and ensure they were available using our emergency use authorities,” said FDA Acting Commissioner Ned Sharpless, M.D. “Today’s marketing authorization is a great demonstration of the FDA’s work to protect the public health in emergency response situations. We ensured there were tests made available quickly under EUA, but we continued to work with diagnostic manufacturers to take the next step of ensuring products were FDA reviewed for safety and effectiveness and authorized under our traditional premarket authorities.”

The ZIKV Detect 2.0 IgM Capture ELISA is designed to identify proteins (antibodies) produced by the body’s immune system when it tests for Zika virus infection in the blood. IgM antibodies indicate an early immune response. The FDA reviewed data from a clinical study of 807 test samples and a variety of analytical studies, which demonstrated that the ZIKV Detect 2.0 IgM Capture ELISA was safe and effective at identifying IgM antibodies against Zika virus in blood.

The ZIKV Detect 2.0 IgM Capture ELISA is for use only in patients with clinical signs and symptoms consistent with Zika virus infection, and/or who meet the CDC’s Zika virus epidemiological criteria, such as history of residence in or travel to a geographic region with active Zika transmission at the time of travel. Results of this test are intended to be used in conjunction with clinical observations, patient history, epidemiological information and other laboratory evidence to make patient management decisions. Negative results may be seen in specimens collected before day four after the onset of symptoms or after the window of detectable IgM closes, and therefore do not preclude the possibility of Zika virus infection, past or present. This test is not authorized by the FDA for testing blood or plasma donors.

Prior to today, all of the available Zika tests had been authorized for use under an EUA, in which the agency allows use of unapproved medical products, or unapproved uses of approved medical products, in an emergency to diagnose, treat or prevent serious or life-threatening diseases or conditions caused by chemical, biological, radiological or nuclear agents.

The FDA can only issue an EUA when specific criteria are met, including that there are no adequate, approved and available alternatives. With the marketing authorization granted for the ZIKV Detect 2.0 IgM Capture ELISA today, the FDA has also revoked the EUA for this device, which was initially authorized for emergency use in 2016. In addition, the FDA is considering whether the ZIKV Detect 2.0 IgM Capture ELISA test is an adequate, approved and available alternative to other currently available Zika virus antibody diagnostic tests available under EUAs. Currently, there are 18 other active EUAs for tests to diagnose Zika virus infection, four of which detect Zika virus antibodies like the ZIKV Detect 2.0 IgM Capture ELISA. The FDA is communicating with the four EUA holders to gather information to evaluate whether the FDA should revoke the EUAs for these specific tests. Today’s marketing authorization does not impact the availability of the 14 other Zika nucleic acid diagnostics available under EUAs.

The FDA granted marketing authorization of the ZIKV Detect 2.0 IgM Capture ELISA to InBios International, Inc.