Therapeutic Drug Monitoring by Pharmacists: Does It Reduce Costs

Optimizing Cefiderocol Dosing Through Population Pharmacokinetic/Pharmacodynamic Simulation: An Assessment of Drug Cost Reductions

BACKGROUND

Cefiderocol is a siderophore cephalosporin antibiotic with bactericidal activity against carbapenem-resistant Enterobacterales. However, an efficient dosing strategy is yet to be developed. This study aimed to evaluate efficient lower-dose regimens and estimate potential drug cost reductions.

METHODS

This simulation study used a virtual population of 10,000 resampled individuals based on a reported population pharmacokinetic model. The target index for maximal bactericidal activity was the time for the unbound cefiderocol concentration to be above the minimum inhibitory concentration (TAM_unbound) of 100%, which was determined using a minimum inhibitory concentration distribution or specific value.

RESULTS

The probability of achieving 100% TAM_unbound with the standard, low- (reduced by 1 g or one dose), and extended low- (reduced by 2 g or 2 doses) dose regimens was nearly 100%. The lowest probability of achieving 100% TAM_unbound with the extended low-dose regimen at a creatinine clearance range of 90-120 mL/min was 86.4%. The probability of achieving TAM_unbound of 100% was more than 90% for MIC of ≤0.5 mcg/mL with the extended low-dosing regimen. Furthermore, using an efficient dosing regimen reduced the medical costs over a 10-day treatment period for 10 patients, from $122,826.50 to $62,665.69 $ and ¥12,598,187 $ to ¥5,451,173 in the United States and Japan, respectively.

CONCLUSIONSS

A lower dosing regimen for cefiderocol could result in substantial reductions in drug costs while still achieving 100% TAM_unbound.

Therapeutic Drug Monitoring as a Tool for Therapy Optimization

The use of pharmacotherapy for improving healthcare in society is increasing. A vast majority of patients have either received subtherapeutic treatment (which could result from low pharmacokinetic) or experienced adverse effects due to the toxic levels of the drug. The medicines used to treat chronic conditions, such as epilepsy; cardiovascular diseases; and oncological, neurological, and psychiatric disorders, require routine monitoring. New targeted therapies suggest an individualized treatment that can slowly move practitioners away from the concept of a one-size-fits-all-fixed-dosing approach. Therapeutic drug use can be monitored based on pharmacokinetic, pharmacodynamic, and pharmacometric methods. Based on the experiences of therapeutic drug monitoring of various agents across the globe, we can look ahead to the possible developments of therapeutic drug monitoring in India.