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. 2023 Jan 16;15(1):299.
doi: 10.3390/pharmaceutics15010299.

Therapeutic Drug Monitoring of Tacrolimus Based on Volumetric Absorptive Microsampling Technique (VAMS) in Renal Transplant Pediatric Recipients-LC-MS/MS Method Development, Hematocrit Effect Evaluation, and Clinical Application

Arkadiusz Kocur  1 , Dorota Marszałek  1 , Jacek Rubik  2 , Agnieszka Czajkowska  3 , Tomasz Pawiński  1
Affiliations

Therapeutic Drug Monitoring of Tacrolimus Based on Volumetric Absorptive Microsampling Technique (VAMS) in Renal Transplant Pediatric Recipients-LC-MS/MS Method Development, Hematocrit Effect Evaluation, and Clinical Application

Arkadiusz Kocur et al. Pharmaceutics. .

Abstract

Tacrolimus (TAC) is post-transplant pharmacotherapy's most widely used immunosuppressant. In routine clinical practice, frequent uncomfortable venipuncture is necessary for whole-blood (WB) collection to check trough TAC levels. Volumetric absorptive microsampling (VAMS) is an alternative strategy to WB collection. In this study, we aimed to validate and develop a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for TAC quantification in WB and VAMS samples. After extraction with water and protein precipitation, the samples were directly analyzed using LC-MS/MS. Whole-blood and VAMS capillary-blood samples were collected from 50 patients treated with TAC during the follow-up visits. The cross-correlation between the developed methods was evaluated using Passing-Bablok regression and a Bland-Altman bias plot. The matrix effect (ME) and carry-over were insignificant for both scenarios. There was a high correlation between the processes and no significant clinical deviation. LC-MS/MS methods were successfully developed and validated in the 0.5-60 ng/mL calibration range. This study demonstrated and confirmed the utility of VAMS-based TAC monitoring in the pediatric population. This is the first study to directly develop and validate the VAMS LC-MS/MS method for evaluating the hematocrit effect in the pediatric population. The statistical correlation between immunochemical and VAMS-based methods was satisfactory.

Keywords: LC-MS/MS; VAMS; hematocrit effect; kidney transplantation; microsampling; pediatric population; tacrolimus; whole blood.

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Conflict of interest statement

The authors declare no conflict of interest. The funders had no role in the study design, collection, analysis, interpretation of data, writing of the manuscript, or decision to publish the results.

Figures

Figure 1
Figure 1
Chemical structures of the reference standard (tacrolimus, TAC) and internal standards (deuterated TAC, 13CD2TAC, and ascomycin, ASC).
Figure 2
Figure 2
Representative chromatograms of two events (1st for TAC and 2nd for ASC respectively) for: (a) whole-blood patient sample—measured concentration: 3.84 ng/mL, (b) VAMS patient sample—measured concentration: 5.15 ng/mL, (c) the LLOQ—0.5 ng/mL for VAMS method, (d) the HQC—60 ng/mL for VAMS method, (e) blank sample (total ion chromatogram—TIC).
Figure 3
Figure 3
Graphical comparison of results obtained by the new VAMS LC-MS/MS method (green line with triangles), reference WB-LC-MS/MS method (red line with circles), and the routinely used automatic CMIA method (blue line with diamonds).
Figure 4
Figure 4
Comparison of TAC concentration results obtained from three described methods: (a) Passing–Bablok regression and Bland–Altman bias plot for WB-LC-MS/MS vs. VAMSLC-MS/MS; (b) Passing–Bablok regression and Bland–Altman bias plots for VAMSLC-MS/MS vs. CMIA; and (c) Passing–Bablok regression and Bland–Altman bias plot for WB-LC-MS/MS vs. CMIA.
Figure 5
Figure 5
Scatter diagrams showing the poor correlation between percent hematocrit value (HCT) and differences in TAC concentrations (ng/mL) between (a) VAMS method results and WB method results for each patient and (b) VAMS method results and CMIA results for each patient. The hot map with color coding indicates the density of points according to the relationship investigation between the compared data.
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References

    1. Papalois V.E., Najarian J.S. Pediatric kidney transplantation: Historic hallmarks and a personal perspective. Pediatr. Transplant. 2001;5:239–245. doi: 10.1034/j.1399-3046.2001.005004239.x. - DOI - PubMed
    1. Kidney Disease: Improving Global Outcomes (KDIGO) Transplant Work Group KDIGO clinical practice guideline for the care of kidney transplant recipients. Am. J. Transplant. 2009;9:S1–S155. doi: 10.1111/j.1600-6143.2009.02834.x. - DOI - PubMed
    1. Brunet M., van Gelder T., Åsberg A., Haufroid V., Hesselink D.A., Langman L., Lemaitre F., Marquet P., Seger C., Shipkova M., et al. Therapeutic Drug Monitoring of Tacrolimus-Personalized Therapy: Second Consensus Report. Ther. Drug Monit. 2019;41:261–307. doi: 10.1097/FTD.0000000000000640. - DOI - PubMed
    1. Seger C., Shipkova M., Christians U., Billaud E.M., Wang P., Holt D.W., Brunet M., Kunicki P.K., Pawiński T., Langman L.J., et al. Assuring the Proper Analytical Performance of Measurement Procedures for Immunosuppressive Drug Concentrations in Clinical Practice: Recommendations of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology Immunosuppressive Drug Scientific Committee. Ther Drug Monit. 2016;38:170–189. doi: 10.1097/FTD.0000000000000269. - DOI - PubMed
    1. Christians U., Vinks A.A., Langman L.J., Clarke W., Wallemacq P., van Gelder T., Renjen V., Marquet P., Meyer E.J. Impact of Laboratory Practices on Interlaboratory Variability in Therapeutic Drug Monitoring of Immunosuppressive Drugs. Ther. Drug Monit. 2015;37:718–724. doi: 10.1097/FTD.0000000000000205. - DOI - PubMed

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