In Vivo Pharmacodynamic Evaluation of Omadacycline against Staphylococcus aureus in the Neutropenic Mouse Pneumonia Model

Omadacycline is an effective therapy for community-acquired bacterial pneumonia (CABP). Given its potent activity against methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA), we sought to determine the pharmacodynamic activity and target pharmacokinetic/pharmacodynamic (PK/PD) exposures associated with a therapeutic effect in the neutropenic mouse pneumonia model against 10 MSSA/MRSA strains. The area under the concentration- time curve (AUC)/MIC associated with 1-log kill was noted at 24-h epithelial lining fluid (ELF) and plasma AUC/MIC exposures of similar to 2 (ELF range, <0.93 to 19; plasma range, <1.06 to 17) and 2-log kill was noted at 24-h ELF and plasma AUC/MIC exposures of similar to 12 (ELF range, 2.5 to 130; plasma range, 3.5 to 151).