A real-world data-driven approach to optimizing enoxaparin dosing in burn patients

Enoxaparin dosing in burn patients is challenging due to physiological changes affecting absorption, distribution and clearance. The objectives of this study are to develop a population pharmacokinetic (PK) model for enoxaparin in burn patients, evaluate target attainment with current equation-based (EQ) dosing and propose an optimized dosing regimen.

Real-world data from 408 burn patients who received enoxaparin for thromboprophylaxis at the University of Utah Burn Center were analysed, comprising 15 517 doses and 1288 antiXa measurements. Only 56% of patients achieved the target antiXa range (0.2-0.4 IU/mL) approximately 4 h after the third dose. A one-compartment PK model with first-order absorption and elimination best fit the data, with estimated apparent clearance (CL/F), volume of distribution (Vc/F) and absorption rate constant at 1.56 L/h, 22.1 L and 1.10 1/h, respectively.

Total burn surface area (TBSA) and body weight significantly influenced clearance and distribution, while glomerular filtration rate had no notable impact. Simulations showed that EQ dosing failed to achieve target levels after the first dose in ~40% of patients, while the proposed model-based regimen improved target attainment by more than 70%. This study underscores the limitations of EQ dosing, and patients with larger TBSA or higher body weight particularly benefited from the proposed regimen.

A population PK model of enoxaparin was developed in burn patients using real-world data. Model-informed dosing improved early prophylactic target attainment compared with EQ dosing, providing a practical strategy for optimizing enoxaparin prophylaxis in this high-risk population.