What is the Vectra DA Test?
The Vectra DA test is a multibiomarker assay that measures RA disease activity. This test measures 12 immune, endothelial, bone, cartilage, and metabolic protein biomarkers (VCAM-1, EGF, VEGF-A, IL-6, TNF-RI, MMP-1, MMP-3, YKL-40, leptin, resistin, SAA, CRP) that reflect the underlying biology of RA. Serum concentrations of the biomarkers are integrated into a proprietary algorithm that generates a single score from 1 to 100 that classifies disease activity as high (>45), moderate (30–44), or low (1–29).
Studies report good correlation with other clinical disease activity measures (disease activity score 28 or DAS28, clinical disease activity index or CDAI, and simplified disease activity index or SDAI). The test may be used as an adjunctive measure of disease activity in specific patients, but data does not suggest a role for routine use in all patients alongside traditional clinical markers of disease activity. The test is approved by Medicare with no cost to patient with a maximum of two tests covered annually. In contrast, out of pocket cost is $989.
Pearl : Interpret Vectra-DA with caution in the setting of tocilizumab use. Studies have shown that test results may be influenced by tocilizumab independent of disease activity. This medication results in elevation of serum IL-6 levels resulting in higher Vectra-DA scores and loss of correlation with other clinical disease activity measures.