Acta Pharmacologica Sinica (2010) 31: 999–1012; doi: 10.1038/aps.2010.79; published online 19 Jul 2010 

Qiu-bai LI^{1, #}, Chao CHEN^{2, #}, Zhi-chao CHEN¹, Hong-xiang WANG³, Yan-lin WU⁴, Yong YOU^{1, *}, Ping ZOU¹ 

¹Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; ²Department of Oncology and Hematology, First Hospital of Wujiang City, Wujiang 215200, China; ³Hematology Department, Wuhan Center Hospital, Wuhan 430022, China; ⁴Wuhan Institute for Drug Control, Wuhan 430022, China

Methods: Fourty-six naïve Chinese CML patients treated with imatinib (400 and 600 mg daily, n=36 and 10, respectively) were recruited. The correlations of imatinib (400 mg) trough plasma concentrations (C_mins) with the patients’ characteristics and responses were analyzed. 

Results: The overall mean (±SD, CV%) steady-state C_mins for imatinib at 400 mg (n=36) and 600 mg (n=10) daily was 1325.61 ng/mL (±583.53 ng/mL; 44%) and 1550.90 ng/mL (±462.63 ng/mL; 30%), respectively, and no statistically significant differences were found between them (P=0.267).  At 400 mg daily, female patients had significantly higher C_mins than the male patients (P=0.048), and molecular responses were not correlated with imatinib C_mins, but they were correlated with time elapsed before imatinib therapy. 

Conclusion: The results suggest that Chinese CML patients have higher imatinib C_mins than their Caucasian counterparts and that the optimal initial imatinib dose for them requires further investigation.

Keywords: trough plasma concentration; imatinib; chronic myelogenous leukemia