First FDA-cleared newborn screening test for SCID

The US Food and Drug Administration (FDA) has cleared for marketing the first screening test for severe combined immunodeficiency (SCID) in newborns.

The EnLite Neonatal TREC Kit uses a few drops of blood from the baby’s heel to test for T-cell receptor excision circles (TREC) DNA. Low or absent TREC DNA typically occurs in newborns with SCID, who then require more testing to diagnose the potentially fatal genetic disorder.  

About 40 to 100 newborns in the United States are diagnosed with SCID every year, according to the Centers for Disease Control and Prevention. They appear normal at birth but without intervention develop life-threatening infections within a few months resulting from their lack of immune response.

Because identifying and treating SCID early can significantly increase survival, the Secretary of the US Department of Health and Human Services and the Advisory Committee on Heritable Disorders in Newborns and Children recommend that every state routinely screen newborns for the condition.

The FDA reviewed the EnLite Neonatal TREC Kit through its de novo classification process for novel low- to moderate-risk medical devices that aren’t significantly equivalent to an already legally marketed device. In a clinical study of around 6400 routine screening blood samples from newborns, including 17 who had confirmed SCID, the kit correctly identified all 17 SCID cases. It also accurately detected the very low TREC DNA values found in children with SCID.

The kit isn’t a diagnostic test for SCID and shouldn’t be used to screen for SCID-like syndromes (DiGeorge syndrome, Omenn syndrome) or less-acute SCID syndromes such as leaky-SCID or variant SCID, the FDA says.

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