A Simple Dosing Scheme for Intravenous Busulfan Based on Retrospective Population Pharmacokinetic Analysis in Korean Patients.
10.4196/kjpp.2012.16.4.273
- Author:
Sangmin CHOE
1
;
Gayeong KIM
;
Hyeong Seok LIM
;
Sang Heon CHO
;
Jong Lyul GHIM
;
Jin Ah JUNG
;
Un Jib KIM
;
Gyujeong NOH
;
Kyun Seop BAE
;
Dongho LEE
Author Information
1. Department of Clinical Pharmacology & Therapeutics, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736, Korea. ksbae@amc.seoul.kr
- Publication Type:Original Article ; Randomized Controlled Trial
- Keywords:
Dosage scheme;
Intravenous busulfan;
Population pharmacokinetics
- MeSH:
Body Weight;
Busulfan;
Female;
Hematopoietic Stem Cell Transplantation;
Humans;
Male;
Prospective Studies;
Retrospective Studies
- From:The Korean Journal of Physiology and Pharmacology
2012;16(4):273-280
- CountryRepublic of Korea
- Language:English
-
Abstract:
Busulfan is an antineoplastic agent with a narrow therapeutic window. A post-hoc population pharmacokinetic analysis of a prospective randomized trial for comparison of four-times daily versus once-daily intravenous busulfan was carried out to search for predictive factors of intravenous busulfan (iBu) pharmacokinetics (PK). In this study the population PK of iBu was characterized to provide suitable dosing recommendations. Patients were randomized to receive iBu, either as 0.8 mg/kg every 6 h or 3.2 mg/kg daily over 4 days prior to hematopoietic stem cell transplantation. In total, 295 busulfan concentrations were analyzed with NONMEM. Actual body weight and sex were significant covariates affecting the PK of iBu. Sixty patients were included in the study (all Korean; 23 women, 37 men; mean [SD] age, 36.5 [10.9] years; weight, 66.5 [11.3] kg). Population estimates for a typical patient weighing 65 kg were: clearance (CL) 7.6 l/h and volume of distribution (Vd) 32.2 l for men and 29.1 L for women. Inter-individual random variabilities of CL and Vd were 16% and 9%. Based on a CL estimate from the final PK model, a simple dosage scheme to achieve the target AUC0-inf (defined as median AUC0-inf with a once-daily dosage) of 26.18 mg/lxhr, was proposed: 24.79xABW0.5 mg q24h, where ABW represents the actual body weight in kilograms. The dosing scheme reduced the unexplained interindividual variabilities of CL and Vd of iBu with ABW being a significant covariate affecting clearance of iBU. We propose a new simple dosing scheme for iBu based only on ABW.
