Dried-Blood-Spot Technique to Monitor Direct Oral Anticoagulants: Clinical Validation of a UPLC-MS/MS-Based Assay
Foerster et al.
The finding, in our words
A DBS assay for apixaban, dabigatran, edoxaban and rivaroxaban met validation criteria across a haematocrit range of 0.33-0.65, with linearity from 2.5-750 ng/mL (apixaban and rivaroxaban), 4.4-750 ng/mL (dabigatran) and 9.3-750 ng/mL (edoxaban), low ion suppression, acceptable precision and accuracy, and stability for 52 days at room temperature protected from light and humidity; in 33 patients, capillary DBS results strongly agreed with plasma concentrations, enabling home self-sampling for DOAC monitoring.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
In AML and CLL, 91% of VAMS venetoclax results fell within 20% of plasma after individualised haematocrit correction; in home sampling, 18 of 21 patients self-sampled independently and 76% of returned samples were analysable, which shows home microsampling is workable, though the authors ask for multicentre validation.
Home DBS sampling gave testosterone results that agreed well with venous blood in men on intramuscular testosterone undecanoate, but showed falsely high values in those using topical gel, likely from skin contamination. Patients preferred home collection for its convenience, suggesting DBS is viable for decentralised monitoring of injectable testosterone if patients are taught proper technique.
Capillary dried blood spot concentrations of levetiracetam agreed closely with plasma, with 92.1% within 20% of the mean and no proportional bias, and capillary matched venous dried blood spot with acceptable deviations; samples remained stable during postal transit, enabling at‑home self‑sampling for therapeutic drug monitoring.
VAMS microsampling found no significant difference from venous blood for tacrolimus in paediatric patients; samples were stable for 14 days, with average difference between paired at-home samples of 0.12 ± 0.94 ng/mL.
Clinical validation for tacrolimus and mycophenolic acid monitoring showed that while volumetric absorptive microsampling met analytical criteria after concentration correction, conventional dried blood spots achieved superior adherence to strict clinical criteria, sample quality, and cost efficiency without significant haematocrit bias.