Ceftazidime-avibactam Versus Doripenem for the Treatment of Complicated Urinary Tract Infections, Including Acute Pyelonephritis: RECAPTURE, a Phase 3 Randomized Trial Program

BACKGROUND: The global emergence of carbapenem-resistant Enterobacteriaceae highlights the urgent need to reduce carbapenem dependence. The phase 3 RECAPTURE program compared the efficacy and safety of ceftazidime-avibactam and doripenem in patients with complicated urinary tract infection (cUTI), including acute pyelonephritis. METHODS: Hospitalized adults with suspected or microbiologically confirmed cUTI/acute pyelonephritis were randomized 1: 1 to ceftazidime-avibactam 2000 mg/500 mg every 8 hours or doripenem 500 mg every 8 hours (doses adjusted for renal function), with possible oral antibiotic switch after ≥5 days (total treatment duration up to 10 days or 14 days for patients with bacteremia). RESULTS: Of 1033 randomized patients, 393 and 417 treated with ceftazidime-avibactam and doripenem, respectively, were eligible for the primary efficacy analyses; 19. 6% had ceftazidime-nonsusceptible baseline pathogens. Noninferiority of ceftazidime-avibactam vs doripenem was demonstrated for the US Food and Drug Administration co-primary endpoints of (1) patient-reported symptomatic resolution at day 5: 276 of 393 (70. 2%) vs 276 of 417 (66. 2%) patients (difference, 4. 0% 95% confidence interval CI, -2. 39% to 10. 42%) ; and (2) combined symptomatic resolution/microbiological eradication at test of cure (TOC): 280 of 393 (71. 2%) vs 269 of 417 (64. 5%) patients (difference, 6. 7% 95% CI,. 30% to 13. 12%). Microbiological eradication at TOC (European Medicines Agency primary endpoint) occurred in 304 of 393 (77. 4%) ceftazidime-avibactam vs 296 of 417 (71. 0%) doripenem patients (difference, 6. 4% 95% CI,. 33% to 12. 36%), demonstrating superiority at the 5% significance level. Both treatments showed similar efficacy against ceftazidime-nonsusceptible pathogens. Ceftazidime-avibactam had a safety profile consistent with that of ceftazidime alone. CONCLUSIONS: Ceftazidime-avibactam was highly effective for the empiric treatment of cUTI (including acute pyelonephritis), and may offer an alternative to carbapenems in this setting. CLINICAL TRIALS REGISTRATION: NCT01595438; NCT01599806.