Cefazolin Versus Penicillin for Penicillin-Susceptible Staphylococcus aureus Bacteremia: A Secondary Analysis of the SNAP Backbone Trials

• Compared to antistaphylococcal beta-lactams, penicillin may be theoretically advantageous due to lower minimal inhibitory concentrations, superior pharmacokinetics and pharmacodynamics, and a narrower spectrum of activity.
• The SNAP Trial MSSA/PSSA domains compared (flu)cloxacillin vs. penicillin and (flu)cloxacillin vs. cefazolin separately, therefore the efficacy of cefazolin vs. penicillin for penicillin-susceptible S. aureus (PSSA) bacteremia was not studied.
• Therefore, we would like to compare penicillin vs. cefazolin for the treatment of PSSA bacteremia indirectly by pooling data from the PSSA and MSSA backbone domains, leveraging (flu)cloxacillin as the common comparator.

Research Question: Is cefazolin or penicillin likely to be superior for the treatment of penicillin-susceptible S.aureus (PSSA) bacteremia?

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