Therapeutic Salivary Monitoring of Perampanel in Patients with Epilepsy Using a Volumetric Absorptive Microsampling Technique
Palmisani et al.
The finding, in our words
The study validated a VAMS based LC-MS/MS assay for perampanel in saliva, demonstrating linear calibration, acceptable accuracy and precision, and stability across storage conditions, and showed clinical applicability in patients with epilepsy, supporting at-home therapeutic drug monitoring.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
Dried saliva collected with the Mitra device correlated strongly with wet saliva but poorly with plasma unbound and total concentrations, indicating it is not a reliable substitute for plasma in routine therapeutic drug monitoring of mycophenolic acid and its glucuronide metabolite. Capillary blood collected via VAMS remains a promising alternative for long term monitoring in paediatric patients.
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.
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.
This review found that volumetric microsampling devices, such as Mitra, HemaPEN, HemaXis DB10, and Tasso-M20, overcome haematocrit bias, whilst Telimmune plasma separation cards enable direct plasma collection without centrifugation. These technologies support patient-centric, decentralised sampling, though the authors note that clinical validation remains limited across different drugs and patient populations.
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.