Safety and efficacy of personalised versus standard dosing of linezolid in patients with sepsis (SePkLin): a pragmatic, multicentre, randomised, controlled and superiority clinical trial protocol

Introduction Linezolid is a broadly used antibiotic to treat complicated infections caused by gram-positive bacteria. Therapeutic drug monitoring of linezolid concentrations is recommended to maximise its efficacy and safety, mainly haematological toxicity. Different pharmacokinetic/pharmacodynamic targets have been proposed to improve linezolid exposure: the ratio of the area under the concentration–time curve during a 24-hour period to minimum inhibitory concentration (MIC) between 80 and 120; percentage of time that the drug concentration remains above the MIC during a dosing interval greater than 85% and the trough concentration between 2 and 7 mg/L. This clinical trial aims to evaluate the safety, efficacy and the clinical and economic utility of personalised dosing of linezolid using Bayesian forecasting methods to attain pharmacokinetic/pharmacodynamic targets, known as model-informed precision dosing.Methods and analysis This is a pragmatic, multicentre, randomised, parallel, controlled, phase IV and low intervention trial. Participants will be randomly assigned 1:1 to each group (n=346 per group). Control group will receive the standard dose of linezolid. Intervention group will receive personalised dosage of linezolid based on pharmacokinetic–pharmacodynamic adjustments. The primary outcome will be the incidence of thrombocytopenia in both groups.Ethics and dissemination This protocol was approved by the Ethical Committee of the Investigation with Medicines of Galicia (code 2022/140) and authorised by the Spanish Agency for Medicines and Medical Devices. The trial is implemented in accordance with the Declaration of Helsinki and the international ethical and scientific quality standard, the Good Clinical Practice. The results will be published in peer-reviewed journals.Trial registration number EudraCT registration code: 2022-000144-30.