Using Monte Carlo simulation to determine optimal dosing regimen for cefetamet sodium for injection

Area of Science:

• Pharmacology and Pharmacokinetics
• Infectious Diseases
• Clinical Pharmacy

Background:

• Cefetamet sodium is an antibiotic requiring optimized dosing for efficacy.
• Pharmacokinetic (PK) and in vitro antibacterial activity data are crucial for determining optimal treatment regimens.
• Monte Carlo simulation is a valuable tool for predicting treatment outcomes and optimizing drug dosage.

Purpose of the Study:

• To determine the optimal cefetamet sodium dosing regimen for Chinese volunteers using pharmacokinetic analysis and Monte Carlo simulation.
• To evaluate the in vitro antibacterial activity of cefetamet sodium against various Gram-negative bacteria.
• To establish a safe, effective, and pharmacoeconomic dosing strategy for cefetamet sodium.

Main Methods:

• A three-cross Latin square, single-dose pharmacokinetic study involving 12 healthy Chinese volunteers receiving 500, 1000, or 2000 mg of cefetamet sodium via IV infusion.
• Plasma drug concentrations were analyzed using high-performance liquid chromatography (HPLC), with PK parameters calculated using DAS2.0 software.
• Monte Carlo simulation was employed to assess the probability of target attainment for bactericidal response (%fT>MIC≧50%) across different dosing regimens.

Main Results:

• Pharmacokinetic parameters including peak concentration (Cmax), area under the curve (AUC0-t), and elimination half-life (t1/2) were determined for each dose.
• Cefetamet sodium demonstrated in vitro sensitivity against key Gram-negative pathogens, including non-extended-spectrum beta-lactamases (ESBL)-producing Enterobacter, Haemophilus influenzae, Moraxella catarrhalis, and Neisseria gonorrhoeae.
• Monte Carlo simulations indicated that the probability of target attainment was achieved with 500 mg q6h, 1000 mg q8h, and 2000 mg q6h regimens for susceptible bacteria.

Conclusions:

• The pharmacokinetic profile of cefetamet sodium appears to follow a two-compartment model with linear kinetics in healthy Chinese volunteers.
• The 500 mg administered every 6 hours (q6h) dosing regimen is recommended based on comprehensive consideration of efficacy, safety, and pharmacoeconomy, aligning with the principle of minimum daily dosage.
• Optimized cefetamet sodium dosing can enhance treatment outcomes for infections caused by susceptible Gram-negative bacteria.