Determination of venlafaxine and O-desmethylvenlafaxine in dried blood spots using LC-MS/MSBerm, E. J. J., Brummel-Mulder, E., Paardekooper, J., Hak, E., Wilffert, B. & Maring, J. G., 1-Oct-2013, In : Therapeutic Drug Monitoring. 35, 5, p. 659-660 2 p.
Research output: Contribution to journal › Article › Academic › peer-review
Background: Venlafaxine (VEN) is an antidepressant which exerts both serotonin and norepinephrine reuptake inhibition. The drug is mainly metabolized by CYP2D6 to its active metabolite O-desmetylvenlafaxine (ODMV). Due to large interindividual differences in clearance in which genetic variance in CYP2D6 activity plays a major role, therapeutic drug monitoring (TDM) is considered useful in patients treated with VEN. We developed an assay for combined determination of VEN and ODMV in dried blood spots (DBS). Methods: A fast and robust LC-MS/MS method was developed and fully validated for simultaneous determination of VEN and ODMV in DBS. 9 mm circles were punched out from DBS collected on Whatman DMPK-C paper and mixed with acetonitril:methanol 1:3 containing the internal standard. The extract was analyzed by LC-MS/MS. Results: The assay was found to be linear in the range 20-1000 mcg/L for both VEN and ODMV. Inter-assay variability at LLQ (20 mcg/L), Low (L, 80 mcg/L), Medium (M, 300 mcg/L) and High (H, 750 mcg/L) levels was 12.0%, 6.1%, 7.0%, and 4.9% for VEN and 10.8%, 6.8%, 5.4%, and 6.3% respectively for ODMV. Bias at LLQ, L, M and H was 7.2%, 1.3%, 0.2%, and 20.4% for VEN and 5.6%, 1.7%, 0.4%, and 0% for ODMV. The influence of punch position and blood volume per spot did not influence the results, but a low hematocrit (10% negative bias. Comparison of venous blood samples with DBS samples revealed a linear correlation with a R2 of >0.98 and a DBS/plasma ratio of 1.11 for VEN and 1.28 for ODMV. Conclusions: This fully validated method is suitable for determination of VEN and its metabolite ODMV in DBS and applicable for TDM. The method will be used in the Dutch CYSCE multicenter trial (ClincialTrail.gov Identifier NCT01778907) in which the effect of CYP2D6 genotyping combined with TDM on time to reach adequate blood drug levels will be investigated in depressed elderly patients.
|Number of pages||2|
|Journal||Therapeutic Drug Monitoring|
|Publication status||Published - 1-Oct-2013|
|Event||13th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology - |
Duration: 22-Sep-2013 → 26-Sep-2013
13th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology
22/09/2013 → 26/09/2013
- Therapeutic drug monitoring, Dried blood spot, Venlafaxine, Antidepressant, CYP2D6, venlafaxine, desvenlafaxine, antidepressant agent, noradrenalin, serotonin, methanol, drug monitoring, dried blood spot testing, toxicology, human, assay, metabolite, patient, genetic variability, drug blood level, multicenter study, blood sampling, venous blood, hematocrit, blood volume, standard, genotype, aged