Detection of imatinib in the plasma and its effect in the patient with chronic myeloid leukemia

Objective To evaluate the relationship between plasma imatinib and its effect in the treatment of chronic myeloid leukemia(CML). Methods Fifty-one CML patients were included in this study,who began taking imatinib from July 2005 to February 2008, with 34 cases of male, and 17 cases of female.Nine patients took imatinib at dose of 300 mg/d, 37 patients took imatinib at dose of 400 mg/d, and 5 patients took imatinib at dose of 600 mg/d. High-performance liquid chromatography was used to test imatinib plasma levels. Results The imatinib plasma levels was imatinib dose-related, and the imatinib plasma trough levels significantly varied between individuals[(342-4688)ng/ml]. The imatinib plasma levels was significant lower in 300 mg/d dose group [(1037±514) ng/ml] than 400 mg/d dose group [(2123±1016) ng/ml] (t =2.34, P =0.032),and the effective rate was 66.7 % (6/9) in 300 mg/d dose group, which was lower than 400 mg/d dose group of 89.19 % (33/37) (χ2=7.14, P =0.008). In 300 mg/d and 400 mg/d dose groups, 39 patients achieved effective treatment, and their imatinib plasma levels was significant higher than that of 7 patients who did not achieved effective treatment (t =2.25, P =0.037). The ROC curve results suggested that clinical treatment may be poor when the imatinib plasma level was lower than 1050 ng/ml (sensitivity was 84.6 %, specificity was 71.1 %).Conclusion The imatinib plasma levels was dose-related, and significantly varied between individuals.Clinical treatment effect may be poor when the imatinib plasma level was lower than 1050 ng/ml. Key words: Leukemia,myeloid,chronic; Imatinib; Plasma trough levels; Treatment outcome