TO THE EDITOR—We conducted a phase 3 trial in patients with uncomplicated urinary tract infection (UTI), comparing oral sulopenem etzadroxil + probenecid with oral ciprofloxacin [1], and we used the Food and Drug Administration’s definition of overall success in studies of UTI, one that requires both clinical cure and microbiologic eradication. In the population of patients with uropathogens that were nonsusceptible to ciprofloxacin, sulopenem was superior to ciprofloxacin (62.6% vs 36.0%; difference, 26.6% [95% confidence interval (CI), 15.1%–37.4%]; P < .001). In the patients with ciprofloxacin-susceptible isolates, sulopenem was not noninferior to ciprofloxacin (66.8% vs 78.6%; difference, −11.8% [95% CI, −18.0 to −5.6). This difference could be attributed to a higher rate of asymptomatic bacteriuria after treatment in patients on sulopenem. In the analysis of all patients, sulopenem was noninferior to ciprofloxacin (65.6% vs 67.9%; difference, −2.3% [95% CI, −7.9 to 3.3]).