NEW YORK (GenomeWeb) – The US Food and Drug Administration is currently reviewing a laboratory-developed molecular assay for Zika virus being offered by Houston Methodist Hospital and Texas Children's Hospital to determine whether it meets the definition of a high-risk medical device and is therefore subject to regulatory oversight.
In a letter dated March 2 and addressed to the test's developers — James Versalovic of Texas Children's and James Musser of Houston Methodist — the FDA noted that the test, which is intended to identify virus-specific RNA sequences to directly detect Zika virus, appears to meet the definition of a device as defined in section 201(h) of the Federal Food Drug and Cosmetic Act.
"Based on our review of your promotional materials, we believe you are offering a high-risk test that has not been the subject of premarket clearance, approval, or Emergency Use Authorization review" by the FDA, the letter said. The FDA further added that it wants to better understand the test's design, validation, and performance characteristics, and noted that the US Centers for Disease Control and Prevention and Centers for Medicare & Medicaid Services have requested that FDA review the science behind the test.
The hospitals began offering the test in late February, claiming to be the first hospitals in the US to offer a rapid molecular assay for the virus. At the time, Musser told GenomeWeb that the hospitals "felt a substantial need to have this test in house with a very rapid turnaround time, which currently is not possible with any other available testing nationally," including a test offered by the CDC.
Musser and Versalovic's diagnostic uses real-time PCR and is based on an assay kit sold by German firm Altona Diagnostics, which has CE marking for IVD use but is marketed in the US for research purposes only.
In a statement issued today, the Association for Molecular Pathology expressed its concern and disappointment over the FDA's enforcement action against the Houston hospital labs, noting that the case is "another clear example of how FDA regulation of [laboratory-developed protocols] would hinder patient access to vital medical services." Given the danger posed by Zika, AMP added, "these types of tests are critical for patient care and should be made available to these patients in need."
The FDA has granted Emergency Use Authorization for one Zika assay, a CDC-developed immunoassay designed to detect antibodies that the body makes to fight a Zika virus infection. However, AMP noted that "antibody testing has limitations mitigated by molecular testing for Zika", as highlighted in a review article recently published in the Journal of Clinical Microbiology by Stanford University researchers.