**7.7 Imipenem-cilastatin-relebactam**

Relebactam is a β-lactamase inhibitor (BLI) diazabicyclooctane that inhibits β-lactamase class A and C activity, but has no activity against metallo-β-lactamase. It has been shown that the combination of imipenem-cilastatin with relebactam has synergistic activity against a broad range of MDR gram negative pathogens including *P. aeruginosa*, KPC-producing *K. pneumoniae and Enterobacter* spp. [143]. This medication has been tested predominantly in patients with IAI, complicated UTI, and pyelonephritis, although a trial is currently underway in patients with HAP/ VAP. Some new medications have a small effect on *P. aeruginosa*, such as plazomycin, meropenem-vaborbactam and aztreonam-avibactam [144].
