Introduction

Effective antimicrobial therapy against bacterial pathogens is becoming increasingly difficult due to the emergence and spread of resistance. Nosocomial spread of MDR Gram-negative species including cephalosporinresistant Enterobacteriaceae, and Acinetobacter producing OXA-type carbapenemases, and MDR Pseudomonas limit therapeutic options. BAL30072 (SFM) is a siderophore-containing monocyclic β-lactam antibiotic currently in Phase I of clinical development (Basilea Pharmaceutica International Limited). It is active against multi-resistant Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter spp., including strains producing Ambler Class A, B and D carbapenemases and in vitro demonstrated synergy with meropenem [1-3] and potent in vivo activity [4]. This study examined the in vivo activities of SFM and meropenem (MER) combinations in neutropenic murine thigh burden models against a range of bacterial strains to confirm in vivo synergy and to define the optimum ratio of SFM and MER.

_{1 Evotec UK, Manchester, United Kingdom}

_{2 Basilea Pharmaceutica International Ltd, Basel, Switzerland}