Plasma Concentration of Itraconazole in Patients With Hematologic Malignancies Treated With Itraconazole Oral Solution.

BACKGROUND: The prophylactic administration of itraconazole (ITCZ) is effective for preventing mycotic infections during chemotherapy in patients with hematologic malignancies. However, fungal infections can occur when the ITCZ does not reach an effective concentration.

METHODS: We conducted a prospective study to monitor the plasma concentration of ITCZ and hydroxyl-ITCZ (OH-ITCZ) weekly and to verify whether the day 3 plasma concentration of ITCZ could predict the subsequent acquisition of an effective plasma concentration.

RESULTS: A total of 39 patients who underwent 66 courses of chemotherapy were assessed in this study. An effective plasma concentration was achieved on day 7 in 34 of 63 patients (54%) and on day 14 in 35 of 59 patients (59%). A univariate analysis revealed that age, type of chemotherapy, and the body surface area were significantly associated with a high plasma concentration of ITCZ + OH-ITCZ. A linear regression analysis extracted the body surface area and the type of chemotherapy as significant factors. An receiver operating characteristic curve analysis revealed a day 3 plasma ITCZ + OH-ITCZ concentration of >656 ng/mL led to a plasma concentration that exceeded the minimum effective level on day 7; the sensitivity and specificity were 62% and 93%, respectively.

CONCLUSIONS: This study showed that the measurement of the day 3 plasma concentration could lead to a better outcome in patients receiving chemotherapy for hematologic malignancies.