Analytical validation of a multi-biomarker algorithmic test for prediction of progressive kidney function decline in patients with early-stage kidney disease

Background The KidneyIntelX™ test applies a machine learning algorithm that incorporates plasma biomarkers and clinical variables to produce a composite risk score to predict a progressive decline in kidney function in patients with type 2 diabetes (T2D) and early-stage chronic kidney disease (CKD). The following studies describe the analytical validation of the KidneyIntelX assay including impact of observed methodologic variability on the composite risk score. Methods Analytical performance studies of sensitivity, precision, and linearity were performed on three biomarkers assayed in multiplexed format: kidney injury molecule-1 (KIM-1), soluble tumor necrosis factor receptor-1 (sTNFR-1) and soluble tumor necrosis factor receptor-2 (sTNFR-2) based on Clinical Laboratory Standards Institute (CLSI) guidelines. Analytical variability across twenty (20) experiments across multiple days, operators, and reagent lots was assessed to examine the impact on the reproducibility of the composite risk score. Analysis of cross-reactivity and interfering substances was also performed. Results Assays for KIM-1, sTNFR-1 and sTNFR-2 demonstrated acceptable sensitivity. Mean within-laboratory imprecision coefficient of variation (CV) was established as less than 9% across all assays in a multi-lot study. The linear range of the assays was determined as 12–5807 pg/mL, 969–23,806 pg/mL and 4256–68,087 pg/mL for KIM-1, sTNFR-1 and sTNFR-2, respectively. The average risk score CV% was less than 5%, with 98% concordance observed for assignment of risk categories. Cross-reactivity between critical assay components in a multiplexed format did not exceed 1.1%. Conclusions The set of analytical validation studies demonstrated robust analytical performance across all three biomarkers contributing to the KidneyIntelX risk score, meeting or exceeding specifications established during characterization studies. Notably, reproducibility of the composite risk score demonstrated that expected analytical laboratory variation did not impact the assigned risk category, and therefore, the clinical validity of the reported results.

Analytical Validation of a New Immunoenzymatic Method for the Measurement of Feline Parathyroid Hormone in Cats with Chronic Kidney Disease

The determination of parathyroid hormone (PTH) in cats could be of clinical utility in many metabolic disorders, such as renal diseases, hypercalcemia, or nutritional imbalances. However, the available methods for the measurement of feline PTH are limited, not widely available, and need radioimmunoassays. The aim of this study was to perform the analytical validation of a new immunoenzymatic method for the measurement of feline PTH. Thirty-eight cats affected with chronic kidney disease (CKD) were included. PTH was measured using a two-site immunoenzymatic method validated in humans and dogs (ST AIA-PACK® Intact PTH, Tosoh Bioscience, Tessenderlo, Belgium). The analytical validation provided the evaluation of precision (intra-assay and inter-assay), accuracy (linearity under dilution (LUD) and spike recovery test (SRT)), and the storage stability of serum samples at 20 °C, 4 °C, and −20 °C. The method showed good precision (intra-assay CVs (coefficient of variations) 3.19–9.61%; inter-assay CVs 9.26–15.28%). In both the intra- and inter-assays, the highest imprecision was found with the low concentration pool (9.61% and 15.28%) and accuracy (LUD and SRT r2 = 0.99, p < 0.001), while the stability was optimal up until 7 days at −20 °C (−7.7%). The method was successfully validated in cats, allowing its future use in diagnostic procedures.

PQ Forum #23. PQ Documents List In Validation Plan

“PQ Forum” provides a mechanism for validation practitioners to share information related to Stage 2 Process Qualification in the validation lifecycle. Information about supporting activities such as design and development, equipment, and analytical validation will also be shared. The information provided should be helpful and practical so as to...

VERIFIKASI METODE ANALISIS METAMFETAMINA DAN AMFETAMINA DALAM MATRIKS URIN SECARA AUTOMATISASI DENGAN GERSTEL® DISPOSABLE PIPETTE EXTRACTION (DPX) MULTIPURPOSE SAMPLER (MPS)

Method analytical validation and verification is crucial in routine qualitative and quantitative analysis. Analysis laboratory need objective evidences about specific parameters in their drugs/analytes or drugs metabolites in matrices biology. Urine is the most preferable matrix biology for determining drugs metabolites especially in drug abuses cases because urine’s sampling process is not invasive. There are many methods extracting drugs in urine, especially methamphetamine and amphetamine as those two analytes are excreted via urine. This study presented method verification for determination of methamphetamine and amphetamine in urine using Gerstel® automated Disposable Pipette Extraction (DPX) Multipurpose Sampler (MPS). Result of this study showed that retention time of methamphetamine is in minute 6.21, and amphetamine is in minute 3.15. Methampethamine’s curve displayed a coefficient of determination r2=0,9999 with the equation y=170,19x+33183. The equation of amphetamine showed y=44390x – 17513 with coefficient of determination r2= 0,9974. Limit of detection (LOD) of methamphetamine in urine is 59,73 ppb, and LOD of amphetamine is 36 ppb.