Pharmacokinetic determinants, clinical efficacy, and safety of teicoplanin in adults: a correlative analysis of plasma concentration and treatment outcomes

Objective The aim of this study was to develop and validate a high-performance liquid chromatography (HPLC) method for the determination of plasma teicoplanin concentrations, identify factors influencing teicoplanin exposure in adult patients, and assess its clinical efficacy and safety. Methods A cohort of 125 adult patients who received teicoplanin therapy at the Second Hospital of Hebei Medical University between June 2022 and March 2023 were retrospectively enrolled. Trough plasma teicoplanin concentrations were determined using a validated HPLC method with quetiapine fumarate as the internal standard. Clinical data, including demographic characteristics, infection type, laboratory parameters, and treatment outcomes, were collected. Logistic regression analyses was conducted to evaluate the clinical efficacy of teicoplanin, attainment of target trough concentrations, and factors associated with these outcomes. Results The HPLC method demonstrated high specificity, satisfactory linearity over the concentration range of 1.5625–100 μg/mL, and acceptable precision, recovery, and stability. Under the standard dosing regimen, only 45.6% of patients achieved a teicoplanin trough concentration (C min ) > 10 mg/L. The overall clinical efficacy rate was 87.20%, and the bacteriological clearance rate was 82.61%. Adverse events included renal injury (8.80%) and hepatic injury (1.60%), with renal injury occurring more frequently in patients with higher C min values. Bivariate analysis showed that teicoplanin trough concentrations were significantly associated with creatinine clearance (CrCL) and plasma albumin levels. Patients with severe renal impairment (CrCL <30 mL min −1 ) were more likely to achieve the target trough concentration. In addition, the incidence of renal injury increased significantly when the trough concentration exceeded 20 mg/L. Conclusion A reliable, accurate, and reproducible HPLC method for the therapeutic drug monitoring of teicoplanin was successfully developed and validated. Application of the validated method presented substantial interindividual variability in teicoplanin plasma concentrations, with CrCL and plasma albumin identified as major factors associated with drug exposure. These findings provide a reliable analytical foundation for future studies of individualized teicoplanin dosing. However, given the retrospective observational design and the absence of real-time therapeutic drug monitoring-guided dose adjustment, the observed associations between trough concentrations and clinical outcomes should be interpreted as exploratory and hypothesis-generating rather than causal.