Simultaneous monitoring of seven antiepileptic drugs by dried blood spot and dried plasma spot sampling: method validation and clinical application of a LC-MS/MS-based technique

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

This study validated a dried blood spot method for tacrolimus monitoring and demonstrated agreement with venous whole blood measurements in kidney transplant recipients. It also found that dried blood spot analysis of the biomarker CXCL-10 was elevated in patients experiencing rejection or infection, supporting its use for decentralised monitoring.

Dried Blood Spot for CXCL-10 and Tacrolimus: Integrated Non-Invasive Monitoring to Guide Personalized Treatment in Adult Kidney Transplant Recipients — Millán et al., Pharmaceuticals · source ↗

• venous-agreement
• blood
• dbs
• tdm
• dried
• immunosuppressants
• validation
• biomarkers

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.

From venipuncture to self-sampling dried blood spots: a shift in monitoring testosterone levels — Olthof et al., Clinical chemistry and laboratory medicine (paywalled) · source ↗

• blood
• dried
• capillary
• dbs
• self-collection
• validation
• venous-agreement
• acceptability
• fertility
• hormones
• tdm

The study validated an LC-MS/MS method for eight antiepileptic drugs and two metabolites in dried blood spot and VAMS formats, with satisfactory analytical performance and stability, and was the first to include the oxcarbazepine metabolite DHCB. In 80 paired patient samples, microsampling concentrations showed promising correlation with plasma, supporting decentralised therapeutic drug monitoring of antiepileptic treatment.

Development and application of an LC-MS/MS method for 8 antiepileptic drugs and 2 metabolites using microsampling techniques (DBS and VAMS) — Cobo-Golpe et al., Journal of analytical toxicology · source ↗

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

In matched clinical samples from rheumatoid arthritis, VAMS and DBS showed strong agreement for methotrexate polyglutamates (slopes 0.95-1.07; bias within -4.21% to 0.36%; SRCC ≥ 0.969), with up to 100% of total MTXPG results within ±20% limits; capillary microsampling agreed closely with whole blood but differed from red blood cells, indicating matrix-specific differences that must be accounted for when interpreting against RBC-based reference values.

Multi-Matrix LC-MS/MS Validation of Methotrexate Polyglutamates: Comparison of VAMS, DBS, and Conventional Blood Sampling in Rheumatoid Arthritis — Kocur et al., International journal of molecular sciences · source ↗

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