2021 · Drug design, development and therapy · open access
Volumetric Absorptive Microsampling as a New Biosampling Tool for Monitoring of Tamoxifen, Endoxifen, 4-OH Tamoxifen and N-Desmethyltamoxifen in Breast Cancer Patients
Maggadani et al.
The finding, in our words
The study validated a VAMS-based LC-MS/MS method for measuring tamoxifen and its active metabolites in breast cancer patients, showing good accuracy, precision and stability at room temperature for 30 days. This supports decentralised therapeutic drug monitoring in oncology by enabling reliable, patient-collected sampling.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
An LC-MS/MS method for tamoxifen and six metabolites in VAMS was developed and validated, with water prerinsing improving recoveries and poor room temperature stability but stability for at least 100 days at minus 80 degrees Celsius. Plasma to blood ratios were used to estimate plasma equivalent concentrations, and paired VAMS and plasma samples from ten breast cancer patients showed strong correlations and good agreement on Bland-Altman analysis, supporting reliable decentralised TDM.
Kuo et al., Analytical and bioanalytical chemistry (paywalled) · source ↗
The study developed and validated a reliable HPLC-MS method for quantifying multiple tyrosine kinase inhibitors from VAMS microsamples of capillary blood, showing acceptable accuracy, precision, and 28-day stability at -21°C, with results comparable to venous plasma in 194 samples from patients with solid tumours. This enables therapeutic drug monitoring using microsamples in oncology practice.
Staudinger et al., Pharmaceutics (paywalled) · source ↗
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.
Shafiei et al., The Journal of pharmacy and pharmacology (paywalled) · source ↗
The study validated an LC-HRMS method for measuring breast cancer drugs in plasma, urine, VAMS and oral fluid, showing that all matrices except oral fluid for certain drugs can support decentralised therapeutic drug monitoring. VAMS and oral fluid faced practical challenges in collection due to patient conditions, but the method enables patient-centric monitoring with dried blood and other self-collected samples.
Jacobs et al., Analytical and bioanalytical chemistry · source ↗
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.
Opitz et al., Journal of chromatography. A (paywalled) · source ↗