Ceftolozane is a novel a cephalosporin-class antibacterial drug. In combination with a beta-lactamase inhibitor tazobactam (ZERBAXA, ceftolozane/tazobactam ) ceftolozane, is currently indicated for the treatment of the adult patients with complicated intra-abdominal infections caused by designated Gram-negative and Gram-positive microorganisms and complicated urinary tract infections caused by certain Gram-negative bacteria, including those caused by multi-drug resistant Pseudomonas aeruginosa. To reduce the development of drug-resistant bacteria and maintain the effectiveness of ZERBAXA and other antibacterial drugs, ZERBAXA should be used only to treat infections that are proven or strongly suspected to be caused by susceptible bacteria. Safety and effectiveness in pediatric patients have not been established.

Tazobactam is a beta-lactamase inhibitor, which was approved by FDA for the treatment of wide range of bacterial infections either in combination with piperacillin (Zosyn) or with ceftolozane (Zerbaxa).

Piperacillin is a semisynthetic, broad-spectrum, ampicillin derived ureidopenicillin antibiotic which exerts bactericidal activity by inhibiting septum formation and cell wall synthesis of susceptible bacteria. Piperacillin sodium salt is used in combination with the β-lactamase inhibitor tazobactam sodium (ZOSYN®) for the treatment of patients with moderate to severe infections caused by susceptible bacteria.