A Review of Blood-Based Microsampling Devices for Patient-Centered Application in Therapeutic Drug Monitoring

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.

Comparison of conventional dried blood spots and volumetric absorptive microsampling for tacrolimus and mycophenolic acid determination — Paniagua-González et al., Journal of pharmaceutical and biomedical analysis (paywalled) · source ↗

• blood
• dried
• capillary
• vams
• dbs
• neoteryx-mitra
• self-collection
• validation
• venous-agreement
• tdm
• immunosuppressants
• economics
• haematocrit

Volumetric absorptive microsampling with Mitra devices permits minimally invasive, finger-prick blood collection for therapeutic drug monitoring of antiseizure medications without trained staff. The review concluded that stability, accuracy and precision are acceptable for specific drugs and haematocrit effects are minimised, but evidence is drug-specific and further validation is required for decentralised clinical use.

Therapeutic Drug Monitoring of Antiseizure Medications Using Volumetric Absorptive Microsampling: Where Are We? — D'Urso et al., Pharmaceuticals · source ↗

• vams
• volumetric
• neoteryx-mitra
• blood
• tdm
• self-collection
• haematocrit
• dried
• capillary
• validation

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.

Clinical Validation of Venetoclax Volumetric Microsampling in Leukemia, with Whole-Blood-to-Plasma Conversion and Self-Microsampling Feasibility — Levens et al., Clinical Pharmacokinetics (paywalled) · source ↗

• vams
• venous-agreement
• blood
• dbs
• tdm
• self-collection
• haematocrit
• dried
• oncology
• capillary
• validation

Volumetric microsampling can enable patient-centred therapeutic drug monitoring with high patient preference and acceptable method validation for many drugs, but conversion from capillary to plasma and agreement with venous sampling varies by analyte and requires careful validation.

Volumetric Microsampling for Patient-Centric Therapeutic Drug Monitoring in Clinical Pharmacology: A Scoping Review — Tummala et al., Journal of clinical pharmacology (paywalled) · source ↗

• volumetric
• venous-agreement
• acceptability
• blood
• tdm
• self-collection
• haematocrit
• dried
• capillary
• validation

This study established conversion methods for estimating plasma concentrations from whole blood VAMS samples for seven out of ten oral anticancer drugs, finding good agreement between capillary and venous samples. Patients reported a positive experience with home sampling using this microsampling technique.

Clinical Application of Volumetric Absorptive Microsampling for Therapeutic Drug Monitoring of Oral Targeted Anticancer Drugs — Meertens et al., Therapeutic drug monitoring · source ↗

• vams
• volumetric
• venous-agreement
• acceptability
• blood
• tdm
• self-collection
• dried
• oncology
• capillary
• validation