DiaSys Procalcitonin FS; DiaSys TruCal Procalcitonin Calibrator Set; DiaSys TruLab Procalcitonin Bi-Level Controls

The DiaSys Procalcitonin FS assay is a particle-enhanced immunoturbidimetric test that quantitatively measures procalcitonin (PCT) levels in human serum and lithium heparin plasma on the Abbott ARCHITECT c8000 analyzer. Measurement of PCT aids in risk assessment of critically ill patients on their first ICU day for progression to severe sepsis and septic shock, used in conjunction with other clinical findings. The submission also includes calibrator and bi-level control materials for the assay.

The subject device uses a particle-enhanced immunoturbidimetric method (PETIA) with polyclonal anti-PCT antibodies bound to polystyrene particles, measured at 660 nm, whereas the predicate VIDAS BRAHMS PCT uses an ELFA (Enzyme-Linked Fluorescent Assay) method on different analyzers. The subject device requires a 10 µL sample volume with 10-minute assay time and measurement range of 0.23–50 ng/mL, compared to the predicate's 200 µL sample, 20-minute time, and 0.05–200 ng/mL range. Both detect the same analyte in the same sample matrices with similar precision and LOB/LOQ performance relevant to clinical decision thresholds.

CLSI EP05-A3 and EP15-A3 (precision and bias estimation), CLSI EP06-A (linearity), CLSI EP17-A2 (detection limits), CLSI EP07-A3 (interference), CLSI EP25-A (stability), CLSI EP09-A3 (method and matrix comparison), and ISO 14971:2019 (risk management).

Although the assay principles differ (immunoturbidimetric vs. ELFA), both methods measure the same analyte in the same sample types and provide equivalent clinical performance: two method comparison studies with ≥100–200 native patient samples showed strong correlation (R ≥0.965), slope within 0.85–1.15, and high percent agreement at clinically relevant PCT cutoffs (0.5 and 2.0 ng/mL). Analytical performance parameters—precision, linearity, LOB/LOQ, stability, freeze-thaw tolerance, and interference testing—all met predefined acceptance criteria and are equivalent to or better than the predicate. The indications for use are identical in clinical intent despite different wording of methodology.