The U.S. Food and Drug Administration (FDA) today granted marketing approval for Cepheid’s Xpert MTB/RIF Assay, making it the “first FDA-reviewed test that can simultaneously detect bacteria that cause tuberculosis (TB) and determine if the bacteria contain genetic markers that makes them resistant to rifampin, an important antibiotic for the treatment of TB,” the agency said.
FDA said that the Sunnyvale, CA-based molecular diagnostic firm’s Xpert MTB/RIF Assay is less complex to perform than previously cleared tests for TB detection. Additionally, the test can detect whether TB bacteria are rifampin-resistant within two hours, as opposed to the one- to three-month turnaround with traditional methods.
The agency reviewed Cepheid’s test through the de novo classification process, through which it evaluates some low- to moderate-risk medical devices that are “not substantially equivalent to an already legally marketed device,” FDA said.
“Less complex tests such as the Xpert MTB/RIF Assay can be used in more diverse settings,” FDA’s Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostics and Radiological Health, said in a statement. “The early and rapid detection of rifampin-resistant TB can help curb the spread of drug-resistant TB, a major public health threat.”
Cepheid said its combination assay first works to detect Mycobacterium tuberculosis complex DNA. In specimens where such DNA is found, the test next works to detect rifampin-resistance associated mutations of the rpoB gene. The firm added that the Xpert MTB/RIF Assay was designed for use on its GeneXpert® Systems.
“Patients with multidrug-resistant TB need more intensive and prolonged therapy,” the company said. According to Cepheid, “Xpert MTB/RIF will enable U.S. clinicians to significantly improve patient outcomes by providing rapid results that guide therapy decisions early in the course of disease, not six weeks later as is the case with standard laboratory methods.”
In a statement, the firm’s chairman and CEO John Bishop said that, “with results available to clinicians in approximately 2 hours instead of weeks, the dramatic impact of Xpert MTB/RIF on identifying TB positive patients and optimizing their drug therapy has been well documented outside of the U.S.” With today’s FDA marketing approval, he added, U.S. clinicians can now “leverage those same transformative results not only for the detection of TB, but also for detecting whether the strain may be multidrug-resistant, requiring more intensive drug therapy.”