Therapeutic Drug Monitoring of Tacrolimus-Personalized Therapy: Second Consensus Report
Brunet et al.
The finding, in our words
An updated international consensus report reviews tacrolimus therapeutic drug monitoring advances, evaluating alternative microsampling approaches such as dried blood spots and volumetric absorptive microsampling alongside pharmacogenetic and immunologic biomarkers to guide personalised immunosuppressive therapy in transplantation.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
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.
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.
A systematic review found mixed economic evidence for microsampling in therapeutic drug monitoring; one study reported no cost reduction with DBS home-sampling, €688 versus €676, whilst another predicted savings up to 61%. The authors caution that more work is required to assess costs alongside clinical outcomes and optimise logistics for decentralised implementation.
A validated offline SPE-LC-MS/MS method using the Mitra microsampling device successfully quantified tacrolimus, cyclosporine A, tryptophan, kynurenine, and creatinine simultaneously. The method met EMA and FDA criteria, showing agreement between capillary and venous sampling, which could facilitate decentralised therapeutic drug monitoring and transplant follow-up through patient self-collection.
This review of 2022 to 2023 work surveys dried blood microsampling for targeted and untargeted metabolomic and lipidomic profiling, finding the approach viable across paediatric research, therapeutic drug monitoring, metabolite screening, biomarker discovery, sports supervision, clinical disorder studies and forensic toxicology. The authors note that dried blood spots and VAMS dominate the published literature over other volumetric formats, and argue that harmonising analytical methods would accelerate wider clinical adoption of microsampling as an alternative to conventional plasma or serum profiling.