Microsampling techniques and patient-centric therapeutic drug monitoring of immunosuppressants

A validated LC-MS/MS method for everolimus using Mitra and Capitainer devices found excellent agreement between capillary microsamples and venous whole blood in 33 adult transplant recipients. The results showed high accuracy and negligible haematocrit effects, supporting the use of microsampling for decentralised therapeutic drug monitoring.

Therapeutic Drug Monitoring of Everolimus Using Volumetric Absorptive Microsampling and Quantitative Dried Blood Spot Methods with LC-MS/MS in Adult Solid Organ Transplant Recipients: An Analytical and Clinical Comparative Study — Kocur et al., Molecules · source ↗

• vams
• venous-agreement
• neoteryx-mitra
• blood
• qdbs
• tdm
• haematocrit
• dried
• capillary
• immunosuppressants
• validation

Deprez et al. validated LC‑MS/MS methods for four immunosuppressants and creatinine from a single 10 μL quantitative dried blood spot. With biases under 10 % and CVs below 8 %, the approach enables accurate patient‑centric therapeutic drug monitoring from capillary blood at home, mitigating the haematocrit effect through volumetric collection.

Liquid chromatography-tandem mass spectrometry for therapeutic drug monitoring of immunosuppressants and creatinine from a single dried blood spot using the Capitainer® qDBS device — Deprez et al., Analytica chimica acta (paywalled) · source ↗

• volumetric
• blood
• qdbs
• tdm
• self-collection
• haematocrit
• dried
• capillary
• immunosuppressants
• validation

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

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

At-home volumetric absorptive microsampling (VAMS) for anti-seizure medicines was feasible and reliable, with strong correlations to clinic VAMS and low bias for lacosamide, lamotrigine and levetiracetam; quantitative dried blood spot (qDBS) was a reliable alternative in the ambulatory setting, though older age reduced sampling quality.

Real-world evaluation of capillary microsampling for drug monitoring of anti-seizure medications — Cancellerini et al., Epilepsia (paywalled) · source ↗

• vams
• venous-agreement
• acceptability
• blood
• qdbs
• tdm
• self-collection
• dried
• capillary