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Harmonization of Busulfan Plasma Exposure Unit (BPEU): A Community-Initiated Consensus Statement. Biol Blood Marrow Transplant 2019 09;25(9):1890-1897



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Scopus ID

2-s2.0-85067678155   6 Citations


Busulfan therapeutic drug monitoring (TDM) is often used to achieve target plasma exposures. Variability in busulfan plasma exposure units (BPEU) is a potential source for misinterpretation of publications and protocols and is a barrier to data capture by hematopoietic cell transplantation (HCT) registry databases. We sought to harmonize to a single BPEU for international use. Using Delphi consensus methodology, iterative surveys were sent to an increasing number of relevant clinical stakeholders. In survey 1, 14 stakeholders were asked to identify ideal properties of a BPEU. In survey 2, 52 stakeholders were asked (1) to evaluate BPEU candidates according to ideal BPEU properties established by survey 1 and local position statements for TDM and (2) to identify potential facilitators and barriers to adoption of the harmonized BPEU. The most frequently used BPEU identified, in descending order, were area under the curve (AUC) in μM × min, AUC in mg × h/L, concentration at steady state (Css) in ng/mL, AUC in μM × h, and AUC in μg × h/L. All respondents conceptually agreed on the ideal properties of a BPEU and to adopt a harmonized BPEU. Respondents were equally divided between selecting AUC in μM × min versus mg × h/L for harmonization. AUC in mg × h/L was finally selected as the harmonized BPEU, because it satisfied most of the survey-determined ideal properties for the harmonized BPEU and is read easily understood in the clinical practice environment. Furthermore, 10 major professional societies have endorsed AUC in mg × h/L as the harmonized unit for reporting to HCT registry databases and for use in future protocols and publications.

Author List

McCune JS, Quinones CM, Ritchie J, Carpenter PA, van Maarseveen E, Yeh RF, Anasetti C, Boelens JJ, Hamerschlak N, Hassan M, Kang HJ, Kanda Y, Paci A, Perales MA, Shaw PJ, Seewaldt VL, Savani BN, Hsieh A, Poon B, Mohty M, Pulsipher MA, Pasquini M, Dupuis LL


Marcelo C. Pasquini MD, MS Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Databases, Factual
Drug Monitoring
Hematopoietic Stem Cell Transplantation
jenkins-FCD Prod-482 91ad8a360b6da540234915ea01ff80e38bfdb40a