Validation and clinical application of dried blood spot assay for quantitative assessment of edoxaban in healthy adults

Aim: Dried blood spot (DBS) is a sampling approach that offers several advantages over plasma and whole blood (WB) sampling, but several factors, such as hematocrit and temperature, can adversely affect quantitation. Methodology & results: In an open-label, three-way crossover study in healthy subjects, we explored the correlation between DBS, WB and plasma samples, and between DBS samples from finger-prick and venipuncture blood for measuring edoxaban and its metabolite M-4 using LC-MS/MS. The methods were validated comprehensively. The incurred sample reanalysis experiments demonstrated quantitation reproducibility in all three matrices. Overall, there was a good correlation (near perfect concordance for edoxaban) among plasma, WB and DBS measurements. M-4 concentrations in DBS and WB were lower than in plasma. Conclusion: These results indicate using DBS may be used as an alternative methodology to measure edoxaban pharmacokinetics.