1. Pharmacokinetics of Levetiracetam Seizure Prophylaxis in Severe Traumatic Brain Injury.
- Author
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Harlan SS, Philpott CD, Keegan SP, Droege ME, Karve AS, Foreman B, Wakefield D, Mueller EW, Sangha K, Ngwenya LB, Courter JD, Desai P, and Droege C
- Subjects
- Humans, Male, Prospective Studies, Middle Aged, Adult, Monte Carlo Method, Critical Illness, Piracetam analogs & derivatives, Piracetam pharmacokinetics, Piracetam administration & dosage, Aged, Half-Life, Levetiracetam pharmacokinetics, Levetiracetam administration & dosage, Anticonvulsants pharmacokinetics, Anticonvulsants administration & dosage, Brain Injuries, Traumatic, Seizures prevention & control, Seizures drug therapy
- Abstract
Background: Drug pharmacokinetics (PK) are altered in neurocritically ill patients, and optimal levetiracetam dosing for seizure prophylaxis is unknown., Objective: This study evaluates levetiracetam PK in critically ill patients with severe traumatic brain injury (sTBI) receiving intravenous levetiracetam 1000 mg every 8 (LEV8) to 12 (LEV12) hours for seizure prophylaxis., Methods: This prospective, open-label study was conducted at a level 1 trauma, academic, quaternary care center. Patients with sTBI receiving seizure prophylaxis with LEV8 or LEV12 were eligible for enrollment. Five sequential, steady-state, postdose serum levetiracetam concentrations were obtained. Non-compartmental analysis (NCA) and compartmental approaches were employed for estimating pharmacokinetic parameters and projecting steady-state trough concentrations. Pharmacokinetic parameters were compared between LEV8 and LEV12 patients. Monte Carlo simulations (MCS) were performed to determine probability of target trough attainment (PTA) of 6 to 20 mg/L. A secondary analysis evaluated PTA for weight-tiered levetiracetam dosing., Results: Ten male patients (5 LEV8; 5 LEV12) were included. The NCA-based systemic clearance and elimination half-life were 5.3 ± 1.2 L/h and 4.8 ± 0.64 hours. A one-compartment model provided a higher steady-state trough concentration for the LEV8 group compared with the LEV12 group (13.7 ± 4.3 mg/L vs 6.3 ± 1.7 mg/L; P = 0.008). Monte Carlo simulations predicted regimens of 500 mg every 6 hours, 1000 mg every 8 hours, and 2000 mg every 12 hours achieved therapeutic target attainment. Weight-tiered dosing regimens achieved therapeutic target attainment using a 75 kg breakpoint., Conclusion and Relevance: Neurocritically ill patients exhibit rapid levetiracetam clearance resulting in a short elimination half-life. Findings of this study suggest regimens of levetiracetam 500 mg every 6 hours, 1000 mg every 8 hours, or 2000 mg every 12 hours may be required for optimal therapeutic target attainment. Patient weight of 75 kg may serve as a breakpoint for weight-guided dosing to optimize levetiracetam therapeutic target attainment for seizure prophylaxis., Competing Interests: Declaration of Conflicting InterestsThe authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: B.F. received honoraria from UCB Pharma and serves on the scientific advisory boards for Marinus Pharmaceuticals, Inc and SAGE Therapeutics. He receives research funding from the National Institutes of Health, US Department of Defense, and National Science Foundation and is the site principal investigator for studies funded by Biogen, Inc and Marinus Pharmaceuticals, Inc. B.F. has no relevant conflicts of interest to this research. L.B.N. conducts traumatic brain injury–related research funded by grants to the University of Cincinnati College of Medicine from Abbott Laboratories and Biogen, Inc. L.B.N. has no relevant conflicts of interest to this research.
- Published
- 2024
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