Fit-for-Purpose Validation of a PK Assay applying Blood Collection by Volumetric Absorptive Microsampling

OBJECTIVES: Validation and application of a fit-for-purpose PK assay used for quantitative analysis of acetaminophen in whole blood applying volumetric absorptive microsampling using MITRA® devices. METHODS: MITRA® devices were evaluated using whole blood samples prepared at different hematocrit values. PK assay parameters precision, accuracy, linearity, LOD, LLOQ, ULOQ, carry-over, and stability of analyte in dried whole blood on MITRA® device were validated following EMA guidelines. Acetaminophen was quantified by LC-HRMS. MITRA® devices were used on selected timepoints post-dose to collect capillary blood after finger prick. Acetaminophen was extracted using methanol containing acetaminophen-d4. RESULTS: Adsorbed whole blood volume ranged from 9.79 ± 0.18, 9.95 ± 0.34, and 10.10 ± 0.48 µL for 20, 45 and 65 % hematocrit. Highest intra-day precision and accuracy were 11.4 % CV and -19.7 %bias at 1 µg/ml. Highest inter-day precision and accuracy were 12.3% CV and -18.8 %bias at 1 µg/mL. Measuring range was 1-25 µg/mL and LOD of 0.30 µg/mL. ACP was stable on Mitra® device tip for up to 4 weeks. Obtained results from the pharmacokinetic study were not significantly different to parameters reported in the literature using plasma samples. CONCLUSIONS: MITRA® devices have a great potential use as an alternative whole blood collection device in comparison with other blood sampling techniques or devices.