A-129 ANALYTICAL VALIDATION OF THE NEXT-GENERATION T-TAS wS SYSTEM

Abstract Background The T-TAS wS instrument is a next-generation instrument used with T-TAS assay chips for the measurement of thrombus formation. The T-TAS wS instrument uses the same scientific principle as the current T-TAS 01 instrument but contains several design and feature enhancements. It is necessary to confirm that these enhancements do not affect assay performance. The T-TAS PL assay was used to evaluate the performance of the T-TAS wS instrument compared to the existing T-TAS 01 instrument. The T-TAS PL assay is a novel in vitro diagnostic assay that passes whole blood through a collagen-coated microcapillary bed at arterial shear stress to measure the platelet thrombus formation process. The test is used to assess overall primary hemostatic function. Results are reported as the area under the pressure-time curve (AUC). The study objective was to validate the accuracy and precision of the next-generation T-TAS wS instrument in comparison with the T-TAS 01 instrument, using the T-TAS PL assay. Methods Accuracy was evaluated using an analytical method comparison following CLSI EP09. To obtain a wide range of AUC results for the method comparison, BAPA anticoagulated blood samples were collected under an IRB-approved protocol from healthy donors, subjects taking antiplatelet therapy, and subjects with von Willebrand disease (N=100 total). Blood samples were measured in duplicate using the T-TAS PL assay with both instruments. Precision was evaluated from the duplicate measurements. The acceptance criteria were a Deming regression line not significantly different from y = x (p < 0.05 considered significant) and duplicate precision < 39 AUC. Results The results from the method comparison indicated that the T-TAS PL assay results from the T-TAS wS and 01 instruments are equivalent, with slope not significantly different from 1 and intercept not significantly different from 0, high correlation coefficient, and equivalent precision. Conclusion The T-TAS wS instrument contains several design and feature improvements compared to the T-TAS 01 instrument, and the results of this study demonstrate that the improvements have not affected assay accuracy or precision.