Oral Tebipenem Pivoxil Hydrobromide in Complicated Urinary Tract Infection

BACKGROUND: There is a need for oral antibiotic agents that are effective against multidrug-resistant gram-negative uropathogens. Tebipenem pivoxil hydrobromide is an orally bioavailable carbapenem with activity against uropathogenic Enterobacterales, including extended-spectrum beta-lactamase-producing and fluoroquinolone-resistant strains. METHODS: In this phase 3, international, double-blind, double-dummy trial, we evaluated the efficacy and safety of orally administered tebipenem pivoxil hydrobromide as compared with intravenous ertapenem in patients with complicated urinary tract infection or acute pyelonephritis. Patients were randomly assigned, in a 1:1 ratio, to receive oral tebipenem pivoxil hydrobromide (at a dose of 600 mg every 8 hours) or intravenous ertapenem (at a dose of 1 g every 24 hours) for 7 to 10 days (or up to 14 days in patients with bacteremia). The primary efficacy end point was overall response (a composite of clinical cure and favorable microbiologic response) at a test-of-cure visit (on day 19, within a ±2-day window) in the microbiologic intention-to-treat population. The noninferiority margin was 12.5%. RESULTS: A total of 1372 hospitalized adult patients were enrolled; 868 patients (63.3%) were included in the microbiologic intention-to-treat population (50.8% of whom had complicated urinary tract infections and 49.2% of whom had pyelonephritis). An overall response was seen in 264 of 449 patients (58.8%) who received tebipenem pivoxil hydrobromide, as compared with 258 of 419 patients (61.6%) who received ertapenem (weighted difference, -3.3 percentage points; 95% confidence interval CI, -9.7 to 3.2). Clinical cure at the test-of-cure visit was observed in 93.1% of the patients in the microbiologic intention-to-treat population who received tebipenem pivoxil hydrobromide and 93.6% of patients who received ertapenem (weighted difference, -0.6 percentage point; 95% CI, -4.0 to 2.8); the majority of patients with microbiologic response failures at the test-of-cure visit were asymptomatic patients with recurrent bacteriuria. Secondary and subgroup analyses were supportive of the primary analysis. Adverse events were observed in 25.7% of patients who received tebipenem pivoxil hydrobromide and in 25.6% of patients who received ertapenem; the most common adverse events were mild diarrhea and headache. CONCLUSIONS: Oral tebipenem pivoxil hydrobromide was noninferior to intravenous ertapenem in the treatment of complicated urinary tract infection and acute pyelonephritis and had a similar safety profile. (Funded by Spero Therapeutics and the Department of Health and Human Services; ADAPT-PO ClinicalTrials.gov number, NCT03788967.).