HPLC-MS Quantification of Multiple Tyrosine Kinase Inhibitors in Patients with Solid Tumors: Method Validation and Clinical Application

Microsampling with Mitra® devices correlated strongly with venous plasma for capecitabine therapeutic drug monitoring (r=0.97), but yielded consistently lower concentrations. Patients preferred this method and reported minimal pain, suggesting it is suitable for patient-centric oncology drug monitoring in decentralised settings.

Comparison of capecitabine concentrations determined by microsampling versus plasma concentrations for therapeutic drug monitoring: a pilot study — Shafiei et al., The Journal of pharmacy and pharmacology (paywalled) · source ↗

• blood
• dried
• capillary
• vams
• neoteryx-mitra
• validation
• venous-agreement
• acceptability
• tdm
• oncology

An on-line SPE-LC-MS method using 10 microlitre capillary blood samples collected on VAMS tips achieved lower limits of quantitation of 0.03 micromolar for methotrexate and 7-OH-MTX and 0.05 micromolar for DAMPA, with acceptable accuracy and precision. A plasma-to-whole-blood correlation factor of 0.46 was observed, supporting low-volume pediatric drug monitoring.

Development and validation of a bioanalytical method for the quantification of methotrexate from serum and capillary blood using volumetric absorptive microsampling (VAMS) and on-line solid phase extraction (SPE) LC-MS — Opitz et al., Journal of chromatography. A (paywalled) · source ↗

• blood
• dried
• capillary
• vams
• neoteryx-mitra
• validation
• pediatric
• tdm
• oncology

Capillary blood collected with the Mitra® device showed correlation with venous samples for paclitaxel therapeutic drug monitoring, but wide confidence intervals suggest the methods may not be interchangeable. While plasma and whole blood concentrations were more closely aligned, the variability raises questions about using self-collected capillary samples for dose individualisation without further validation.

Paclitaxel and Therapeutic Drug Monitoring with Microsampling in Clinical Practice — Radovanovic et al., Pharmaceuticals · source ↗

• blood
• liquid
• dried
• capillary
• vams
• neoteryx-mitra
• validation
• venous-agreement
• tdm
• oncology

LC-MS/MS assays successfully validated the quantitation of giredestrant in dried whole blood across 1 to 1000 ng/ml using Mitra and Tasso-M20 microsampling devices. Quantitation was unaffected by haematocrit, hyperlipidaemia or anticoagulants, with ambient stability documented for 84 days on Mitra and 28 days on Tasso-M20.

Volumetric absorptive microsampling-LC-MS/MS assays for quantitation of giredestrant in dried human whole blood — Johnson et al., Bioanalysis (paywalled) · source ↗

• blood
• dried
• capillary
• vams
• neoteryx-mitra
• validation
• tdm
• oncology
• haematocrit

The authors validated an LC-MS and LC-MS/MS method for quantifying axitinib from 10 microlitre capillary blood collected by VAMS, demonstrating within- and between-run precision within 14% CV and accuracy between 81 and 116% against plasma as the gold standard, making the approach suitable for therapeutic drug monitoring in ambulatory and clinical care.

Development and validation of a bioanalytical method for the quantification of axitinib from plasma and capillary blood using volumetric absorptive microsampling (VAMS) and on-line solid phase extraction (SPE) LC-MS — Opitz et al., Journal of pharmaceutical and biomedical analysis (paywalled) · source ↗

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