2020 · Drug design, development and therapy · open access
Volumetric Absorptive Microsampling as a Sampling Alternative in Clinical Trials and Therapeutic Drug Monitoring During the COVID-19 Pandemic: A Review
Harahap et al.
The finding, in our words
The review highlights that volumetric absorptive microsampling enables easy, minimally invasive home sampling with room temperature storage and fixed volume accuracy, making it a viable alternative for clinical trials and therapeutic drug monitoring during the COVID-19 pandemic.
A paraphrase to the Library’s standard, never the abstract. The source is one link away and is always the authority.
In 55 patients, four approaches to convert dried capillary blood concentrations to plasma equivalents were evaluated. All methods except haematocrit-based conversion yielded acceptable analytical and clinical agreement for paracetamol and metabolites, supporting the reliability of capillary microsampling for decentralised therapeutic drug monitoring.
The authors developed and validated a workflow that couples Mitra volumetric absorptive microsampling with hybridisation LC-MS/MS to quantify the antisense oligonucleotide fomivirsen in human blood. Quantitative recovery was achieved irrespective of haematocrit level or sample age, and the method demonstrated sensitivity, linearity, precision, accuracy, and four-month stability, supporting its use for therapeutic drug monitoring of biologic candidates in decentralised trials.
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.
The study validated an LC-MS/MS method for eight antiepileptic drugs and two metabolites in dried blood spot and VAMS formats, with satisfactory analytical performance and stability, and was the first to include the oxcarbazepine metabolite DHCB. In 80 paired patient samples, microsampling concentrations showed promising correlation with plasma, supporting decentralised therapeutic drug monitoring of antiepileptic treatment.