The FDA has issued a warning letter to COVID-19 antigen test manufacturer Innova Medical Group and called on the company to stop marketing an unapproved test.

Clinical study data the company submitted to the agency in a request for Emergency Use Authorization (EUA) for the antigen test “was identical to data previously provided by other manufacturers in their separate EUA requests,” the agency said, raising concerns about the data’s reliability and accuracy.

The warning letter stemmed from an inspection of the company’s Pasadena, Calif., manufacturing facility that took place from mid-March through April 9.