Predictors of target initial teicoplanin trough concentration attainment in patients with hematological malignancies: a retrospective cohort study

Teicoplanin (TEIC) is frequently used at Osaka Metropolitan University Hospital to treat infections caused by gram-positive cocci in patients with hematological malignancies. However, in certain cases, the initial trough concentrations failed to reach the target level, despite appropriate loading doses. Therefore, this study aimed to identify the factors associated with achieving target concentrations based on the initial trough level following TEIC loading in patients with hematological malignancies. We retrospectively analyzed patients with hematological malignancies treated with TEIC between January 2016 and December 2022. Patients were classified into a target trough attainment group (trough ≥ 15 µg/mL) and a non-attainment group (trough < 15 µg/mL) according to the initial trough concentration measured on day 4 after administering the loading doses. Demographics, clinical laboratory data, TEIC dosing, and concomitant medications were compared between groups. Factors independently associated with the target trough concentration were assessed using multivariate logistic regression analysis. Among the 176 patients, 90 (51%) achieved the target trough concentration, while 86 (49%) did not. Multivariate analysis identified febrile neutropenia, history of bone marrow transplantation within 30 days, presence or absence of tacrolimus (TAC) coadministration, and cumulative TEIC dose over the first 3 days as independent predictors of target attainment. The target concentration attainment rate was only 22% among patients with febrile neutropenia who received a TEIC cumulative loading dose of < 40 mg/kg over the first 3 days after initiation and did not receive TAC coadministration. Achieving adequate TEIC concentrations early in therapy is critical for the successful treatment of immunocompromised patients with hematological malignancies. Our findings indicated that the likelihood of target trough concentration attainment markedly reduced in patients with multiple risk factors for subtherapeutic exposure. Accordingly, higher doses should be administered, particularly to patients with these factors.