FDA Sends Three Letters Over Unapproved Zika Diagnostics

The US Food and Drug Administration (FDA) is taking steps to enforce its oversight of diagnostic tests used to detect the Zika virus, with three new letters to two laboratories and two Texas hospitals for marketing what it says are "high risk" unapproved diagnostics.

The letters, sent to MD Biosciences, First Diagnostic Corp. and two Texas hospitals, Texas Children's and Houston Methodist Hospital, call on the recipients to contact the agency within seven days to discuss their respective tests.

"We believe you are offering a high risk test that has not been the subject of premarket clearance, approval, or Emergency Use Authorization (EUA)," James Woods, deputy director of patient safety and product quality at the Center for Devices and Radiological Health's Office of In Vitro Diagnostics wrote in each of the letters.

In an email on Monday, FDA spokesperson Eric Pahon told Focus: "While FDA encourages laboratories to develop Zika tests, these tests should not be used for clinical diagnoses without the FDA's approval, clearance, or authorization. Because of the serious public health impact of the Zika virus in certain populations, the FDA is requesting that those with tests for the detection of Zika virus in patient samples submit a request for emergency use authorization (EUA) to the agency. EUA is a streamlined regulatory process by which medical products may enter the marketed in an expedited manner."

First Diagnostics Corporation and MD Biosciences

In the letters to First Diagnostic Corporation and MD Biosciences, Woods wrote, "In light of the current public health emergency, it is particularly important for the FDA to review information related to your [tests'] design, validation, and performance characteristics."

However, Jonathan Barash, president of First Diagnostic Corporation, told Focus his company has neither marketed, nor completed development of a Zika diagnostic, and says he believes FDA misinterpreted a statement on First Diagnostic's website.

Barash said his company met with FDA officials, including Woods, via teleconference last Thursday to discuss the test. During the call, Barash said he "quickly explained … we're not selling products, we're not marketing products, we're in development of a product," adding that FDA seemed relieved to learn that.

According to Barash, his company agreed to update its website to clarify that its test is still in development and is not available for sale in the US and is asking FDA to withdraw its letter.

Barash also told Focus his company had applied to two grants to fund the test's development, one from the National Institutes of Health and one from the UK's Medical Research Council.

In February, MD Biosciences also announced it had developed a nucleic acid test that could detect Zika using a patient's blood, plasma, serum or urine in a matter of hours. In an update to its announcement, the company says it will no longer offer its test until it receives clarification from FDA "regarding any pre-market approval requirements."

Last week, MD Biosciences CEO Eddie Moradian told Focus his company had received FDA's letter and welcomed a discussion with the agency to clarify any requirements for clearance or approval, but declined to comment further.

Texas Children's and Houston Methodist Hospital

In its letter to the two hospitals, FDA indicated that it had been asked to review the hospitals' Zika Direct Test by the Centers for Disease Control and Prevention (CDC) and Centers for Medicare and Medicaid Services (CMS).

In February, the hospitals announced they had developed the first rapid diagnostic to detect Zika.

"The FDA would like to better understand the test's design, validation and performance characteristics, and in addition, CDC and CMS have asked us to review the science behind your test. We believe that due to the current public health emergency it is appropriate for the Food and Drug Administration to review information related to the development of the test," the agency wrote.

In a statement sent to Focus via email Monday, Christy Brunton, director of external communications for Texas Children's Hospital, told Focus the two hospitals are "working collaboratively with [FDA] and sharing information regarding the tests' design, validation and performance characteristics."

Brunton also said that "FDA has not asked us to discontinue use of our tests," adding that the tests are only available to patients registered at the hospitals.

FDA and Zika Diagnostics

On 26 February, FDA cleared the first diagnostic to detect Zika. The test, referred to as Zika MAC-ELISA, was developed by CDC and works by detecting the presence of anti-Zika antibodies in a patient's blood or cerebrospinal fluid.

The following week, FDA's Acting Chief Scientist Dr. Luciana Borio told Congress the agency is working with "several" diagnostic companies on tests for Zika, and that the agency will coordinate with clinical labs seeking to develop their own tests.

"In recent weeks, we have seen an increased interest by clinical laboratories to develop their own tests for Zika … To support these efforts, FDA developed simple templates that developers can submit … for expedited review," Borio said, adding that the agency "is urging developers to work with us to ensure their tests meet the standards for accuracy and precision."

Borio also noted that the agency would "not hesitate to take appropriate action to prevent the use of tests that do not meet [the agency's] standards."

Pahon also explained how the templates Borio mentioned can help speed access to emergency use diagnostics, saying, "The templates describe in detail what data is needed for assay validation and are intended to help developers, including laboratories, generate the necessary evidence required in order to be authorized for use in a time-sensitive manner."

FDA Letter – MD Biosciences

FDA Letter – Texas Children's Hospital & Houston Methodist Hospital

FDA Letter – First Diagnostic Corporation