Analytical and clinical validation of dried blood spot and volumetric absorptive microsampling for measurement of tacrolimus and creatinine after renal transplantation

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

In adult kidney transplant patients, fingerprick VAMS and dried blood spot microsampling achieved accurate simultaneous measurement of tacrolimus, mycophenolic acid, and prednisolone compared with venepuncture. The authors noted an overall preference for VAMS over conventional dried blood spots.

Fingerprick Microsampling Methods Can Replace Venepuncture for Simultaneous Therapeutic Drug Monitoring of Tacrolimus, Mycophenolic Acid, and Prednisolone Concentrations in Adult Kidney Transplant Patients — Scuderi et al., Therapeutic drug monitoring (paywalled) · source ↗

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

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

VAMS sampling can replace venous whole blood sampling for tacrolimus trough concentration monitoring after slope correction, but VAMS is currently inferior to DBS because a higher proportion of VAMS samples were of insufficient quality and fewer VAMS results met the predefined acceptance limit compared with DBS.

Volumetric absorptive microsampling and dried blood spot microsampling vs. conventional venous sampling for tacrolimus trough concentration monitoring — Veenhof et al., Clinical chemistry and laboratory medicine (paywalled) · source ↗

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

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