Sulopenem for the Treatment of Complicated Urinary Tract Infections Including Pyelonephritis: A Phase 3, Randomized Trial

Background Sulopenem is a thiopenem antibiotic being developed for the treatment of multidrug-resistant infections. The availability of both intravenous (IV) and oral formulations will facilitate earlier hospital discharge. Methods Hospitalized adults with pyuria, bacteriuria, and signs and symptoms of complicated urinary tract infection (cUTI) were randomized to 5 days of IV sulopenem followed by oral sulopenem etzadroxil/probenecid or 5 days of IV ertapenem followed by oral ciprofloxacin or amoxicillin-clavulanate, depending on uropathogen susceptibility. The primary end point was overall combined clinical and microbiologic response at the test-of-cure visit (day 21). Results Of 1392 treated patients, 444 and 440 treated with sulopenem and ertapenem, respectively, had a positive baseline urine culture and were eligible for the primary ef?cacy analyses. Extended-spectrum beta-lactamase-producing organisms were identified in 26.6% of patients and fluoroquinolone-nonsusceptible pathogens in 38.6%. For the primary end point, noninferiority of sulopenem to the comparator regimen was not demonstrated, 67.8% vs 73.9% (difference, -6.1%; 95% confidence interval, -12.0 to -.1%). The difference was driven by a lower rate of asymptomatic bacteriuria in the subgroup of ertapenem-treated patients who stepped down to ciprofloxacin. No substantial difference in overall response was observed at any other time point. Both IV and oral formulations of sulopenem were well-tolerated and compared favorably to the comparator. Conclusions Sulopenem followed by oral sulopenem-etzadroxil/probenecid was not noninferior to ertapenem followed by oral step-down therapy for the treatment of cUTIs, driven by a lower rate of asymptomatic bacteriuria in those who received ciprofloxacin. Both formulations of sulopenem were well-tolerated. In this phase 3, double-blind, double-dummy study comparing intravenous (IV) sulopenem followed by oral sulopenem to IV ertapenem followed by oral ciprofloxacin or amoxicillin-clavulanate in patients with complicated urinary tract infections, sulopenem was not noninferior to the comparator regimen for overall combined clinical and microbiologic response.