Quantitative dried blood spot microsampling for therapeutic drug monitoring of -antiseizure medications by design of experiment and UHPLC-MS/MS

This study validated a method for monitoring mycophenolic acid in paediatric patients, demonstrating that quantitative dried plasma spots achieved close agreement with venous plasma. Quantitative dried blood spots showed significant haematocrit-related bias, making the plasma-based format more suitable for decentralised monitoring.

Matrix fidelity in microsampling: Plasma-first LC-MS/MS quantification of mycophenolic acid and MPAG — Kocur et al., Journal of chromatography. B, Analytical technologies in the biomedical and life sciences (paywalled) · source ↗

• venous-agreement
• blood
• qdbs
• tdm
• haematocrit
• dried
• pediatric
• immunosuppressants
• validation

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

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

In lung and renal transplant recipients, VAMS sampling with LC-MS/MS quantification of mycophenolic acid and tacrolimus showed good linearity and accuracy, and with a haematocrit-adjusted conversion formula achieved clinical agreement in most samples; tacrolimus did not require haematocrit correction. The approach is virtually painless and enables richer sampling for more accurate drug exposure estimates, supporting decentralised therapeutic drug monitoring.

Evaluation of hematocrit-adjusted conversion strategies for mycophenolic acid and tacrolimus monitoring using volumetric absorptive microsampling in lung and renal transplant recipients — Juan et al., Journal of pharmacy & pharmaceutical sciences : a publication of the Canadian Society for Pharmaceutical Sciences, Societe canadienne des sciences pharmaceutiques · source ↗

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

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