The FDA has granted a Breakthrough Device designation to Quanterix’s Simoa phospho-Tau 181 (pTau-181) blood test for Alzheimer’s disease.

The assay measures the concentration of the pTau-181 protein in human serum and plasma using the company’s HD-X immunoassay system. The protein is a biomarker that suggests brain changes from Alzheimer’s, according to the National Institutes of Health.

The Quanterix test can “detect low-abundance markers in a blood sample, unlocking the possibility for earlier, more accessible, noninvasive diagnosis of disease, including [Alzheimer’s disease],” the company said.