In Vitro Activity of Tedizolid in Comparison with Other Oral and Intravenous Agents Against a Collection of Community-Acquired Methicillin-Resistant Staphylococcus aureus (2014–2015) in the United States

Abstract

Tedizolid activity was compared with other agents with oral and intravenous formulations against community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA). Tedizolid (MIC50/90, 0.12/0.12 mg/L; 100.0% susceptible) was the most potent agent tested against CA-MRSA and subsets from adult and pediatric patients. Tedizolid minimum inhibitory concentrations (MICs) were twofold to fourfold lower than daptomycin (MIC50/90, 0.25/0.5 mg/L; 99.9-100% susceptible) and fourfold to eightfold lower than linezolid (MIC50/90, 1/1 mg/L; 100.0% susceptible), ceftaroline (MIC50/90, 0.5-1/1 mg/L; 96.6-98.8% susceptible), and vancomycin (MIC50/90, 0.5-1/1 mg/L; 100.0% susceptible) against CA-MRSA and subsets. Clindamycin resistance rates among CA-MRSA from pediatric and adult patients were 18.3-19.1% (13.4-14.2% constitutive, 4.9-6.4% inducible) and 36.2-37.6% (29.8-30.1% constitutive, 6.4-7.5% inducible), respectively. Tetracycline (90.4-96.4% susceptible) and trimethoprim-sulfamethoxazole (96.2-100.0% susceptible) were active against CA-MRSA or subsets, whereas erythromycin (83.8-89.4% nonsusceptible) and levofloxacin (50.2-70.8% nonsusceptible) had limited activities. Tedizolid had MIC50/90 values of 0.12/0.12 mg/L against CA-MRSA showing clindamycin constitutive-resistance and recovered from adult or pediatric patients. Tedizolid had potent activities against CA-MRSA, regardless of clindamycin phenotype or patient population. Tedizolid may be considered for the treatment of ABSSSI in adults. Further studies are warranted for the clinical development in the pediatric population.