Comparing probability of target attainment against Staphylococcus aureus for ceftaroline fosamil, vancomycin, daptomycin, linezolid, and ceftriaxone in complicated skin and soft tissue infection using pharmacokinetic/pharmacodynamic models

• Published in: Diagnostic microbiology and infectious disease Vol. 99; no. 4; p. 115292
• Main Authors: Cristinacce, Andrew, Wright, James G, Macpherson, Merran, Iaconis, Joseph, Das, Shampa
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2021
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Anti-Bacterial Agents - pharmacology; Ceftaroline; Ceftaroline fosamil; Ceftriaxone - pharmacology; Ceftriaxone - therapeutic use; Cephalosporins - pharmacology; Cephalosporins - therapeutic use; Child; Computer Simulation; Daptomycin - pharmacology; Daptomycin - therapeutic use; Humans; Linezolid - pharmacology; Linezolid - therapeutic use; Microbial Sensitivity Tests; Middle Aged; Models, Biological; Probability of target attainment; Skin Diseases, Bacterial - drug therapy; Skin Diseases, Bacterial - microbiology; Soft Tissue Infections - drug therapy; Soft Tissue Infections - microbiology; Staphylococcal Infections - drug therapy; Staphylococcal Infections - microbiology; Staphylococcus aureus; Staphylococcus aureus - drug effects; Vancomycin - pharmacology; Vancomycin - therapeutic use; Young Adult; Ceftaroline fosamil; Staphylococcus aureus; Probability of target attainment
• ISSN: 0732-8893; 1879-0070; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2020.115292

•Ceftaroline achieved PTA >99.9% against Staphylococcus aureus at the MIC90 from recent surveillance.•The other antibiotics generally failed to achieve PTAs >90%, even at high doses.•Some cSSTI drugs do not achieve high PTAs relative to contemporary MIC90 estimates. For recently licensed antibiotics, such as the cephalosporin ceftaroline fosamil, probability of target attainment (PTA) curves, showing the percentage of patients reaching a predefined pharmacokinetic (PK)/pharmacodynamic (PD) target at different bacterial minimum inhibitory concentrations (MICs), have been used to support and justify dose recommendations across patient populations. However, information on PTA for older antibiotics is limited. A retrospective analysis was conducted to construct PTA curves for 4 antibiotics against Staphylococcus aureus in patients with complicated skin and soft tissue infections (cSSTIs). PK models for vancomycin, linezolid, daptomycin, and ceftriaxone were selected from the literature based on large numbers of subjects with covariates representative of patients in Europe and/or the United States. An existing model was available for ceftaroline fosamil. Standard and high-dosage regimens were used to compare the PTA of each antibiotic at MIC values 0.03 to 64 mg/L for a simulated set of patients with cSSTI caused by S. aureus. These were compared to proportions of S. aureus isolates at each MIC from global surveillance data. Ceftaroline achieved PTAs >99.9% for bacteriostatic and bactericidal targets at the MIC90 (1 mg/L), whereas the comparators failed to achieve PTAs >90%, at bacteriostatic or bactericidal targets, even when clinical doses were increased beyond those recommended. PTA analysis can be used to compare different drugs with the same simulated patient dataset, subject to availability of an appropriate PK model and robust exposure targets. This analysis shows that some antibiotics commonly used to treat cSSTIs may fail to reach high PTAs relative to contemporary MIC90 estimates.