Pharmacodynamics of Ceftazidime plus Avibactam against KPC-2-Bearing Isolates of Klebsiella pneumoniae in a Hollow Fiber Infection Model

= 2.19 mg/liter), concordant with the observed bacterial burden decline. A threshold analysis identified time > 4 mg/liter of avibactam as the index most closely linked to bacterial burden decline. Given the clinical outcomes seen with KPC-bearing organisms and the toxicities that occur when patients are treated with currently available polymyxins, drugs such as CAZ/AVI should have a prominent place in early therapy.