A phase III, multicenter, double-blind, randomized clinical trial to evaluate the efficacy and safety of ceftolozane/tazobactam plus metronidazole versus meropenem in Chinese participants with complicated intra-abdominal infections

•Phase III study of ceftolozane/tazobactam (C/T) plus metronidazole for complicated intra-abdominal infection in China.•C/T plus metronidazole was noninferior to meropenem for clinical response.•Safety was comparable between C/T plus metronidazole and meropenem groups.•C/T plus metronidazole had efficacy against extended-spectrum β-lactamase-positive Enterobacterales.