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

The study validated a VAMS-based LC-MS/MS method for measuring sirolimus levels, showing it was clinically equivalent to the standard whole blood method and suitable for therapeutic drug monitoring in paediatric transplant patients, supporting the use of decentralised microsampling for this purpose.

Personalization of pharmacotherapy with sirolimus based on volumetric absorptive microsampling (VAMS) in pediatric renal transplant recipients-from LC-MS/MS method validation to clinical application — Kocur et al., Pharmacological reports : PR · source ↗

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

A study of 50 paediatric renal transplant recipients found that a validated VAMS LC-MS/MS method for tacrolimus showed high correlation with the reference method over 0.5–60 ng/mL, with minimal haematocrit effect.

Therapeutic Drug Monitoring of Tacrolimus Based on VAMS in Renal Transplant Pediatric Recipients — LC-MS/MS Method, Hematocrit Effect, and Clinical Application — Kocur et al., Pharmaceutics · source ↗

• vams
• venous-agreement
• neoteryx-mitra
• blood
• tdm
• haematocrit
• dried
• capillary
• pediatric
• 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 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

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