Clinical and Microbiological Outcomes of Ceftazidime-Avibactam Treatment in Adults with Gram-Negative Bacteremia: A Subset Analysis from the Phase 3 Clinical Trial Program

Introduction This exploratory analysis assessed efficacy and safety outcomes in patients with Gram-negative bacteremia treated with ceftazidime-avibactam or comparator across five phase 3, randomized, controlled, multi-center trials in adults with complicated intra-abdominal infection (cIAI), complicated urinary tract infection (cUTI)/pyelonephritis, hospital-acquired pneumonia (HAP), and ventilator-associated pneumonia (VAP). Methods In each trial, RECLAIM and RECLAIM 3 (cIAI; NCT01499290/NCT01726023), REPRISE (cIAI/cUTI; NCT01644643), RECAPTURE (cUTI; NCT01595438/NCT01599806), and REPROVE (HAP/VAP; NCT01808092), patients were randomized 1:1 to intravenous ceftazidime-avibactam (plus metronidazole for those with cIAI) or comparators (carbapenems in > 97% patients) for 5–21 days. Efficacy assessments included clinical and microbiological responses at the test-of-cure visit in the pooled Gram-negative extended microbiologically evaluable (GNeME) population (bacteremia subset). Safety outcomes were summarized for patients with positive bacterial blood culture(s) at baseline who received ≥ 1 dose of study treatment. Results The overall safety population included 4050 patients (ceftazidime-avibactam, n = 2024; comparator, n = 2026). The GNeME population (bacteremia subset) comprised 101 patients (ceftazidime-avibactam, n = 54; comparator, n = 47). Clinical cure rates (all indications combined) were 47/54 (87.0%) for ceftazidime-avibactam and 39/47 (83.0%) for comparators; favorable microbiological response rates were 43/54 (79.6%) and 32/47 (68.1%), respectively. Clinical and microbiological responses in the bacteremia subset were generally similar to those in the overall set. The pattern of adverse events in patients with bacteremia was similar between treatment groups and was consistent with the known safety profile of ceftazidime-avibactam. Conclusion This analysis provides supportive evidence of the efficacy and safety of ceftazidime-avibactam in patients with Gram-negative bacteremia associated with cIAI, cUTI/pyelonephritis, or HAP/VAP.