Oral Sulopenem as effective as Amoxicillin/Clavulanate for Uncomplicated UTI in Women: Phase 3 trial

Researchers have found in a phase 3 REASSURE trial that oral Sulopenem etzadroxil/probenecid was as effective amoxicillin/clavulanic acid (Augmentin®) in treatment of uncomplicated urinary tract infection (uUTI) in adult women.

"We are very pleased to announce positive data from this confirmatory trial, which was conducted under special protocol assessment (SPA) agreement with the U.S. Food and Drug Administration (FDA)," said Corey Fishman, Iterum's Chief Executive Officer. "With the positive data from this trial, we plan to resubmit our New Drug Application (NDA) for oral sulopenem for the treatment of uUTI in the second quarter of 2024. At the same time, with these results in hand, we will be focusing on a strategic process to sell, license, or otherwise dispose of our rights to sulopenem with the goal of maximizing value for our stakeholders. We believe there is tremendous value in sulopenem as a potential new, oral antibiotic for the uUTI indication which has over 30 million infections annually in the U.S., rising resistance to all currently prescribed oral antibiotics, and a complete lack of new product innovation over the last 20 years."

Results demonstrate that oral sulopenem was non-inferior to Augmentin® with respect to the trial's primary endpoint, overall response (combined clinical cure plus microbiologic eradication) at the test-of-cure (TOC) visit in the microbiological-modified-intent-to-treat susceptible (m-MITTS) population. Oral sulopenem showed overall success in 61.7% of patients compared to 55.0% for Augmentin®, demonstrating statistically significant superiority of oral sulopenem versus Augmentin®.

The table below summarizes the key efficacy data from the REASSURE trial at the TOC visit:

[i] Difference in oral sulopenem versus Augmentin® in the m-MITTS population

[ii] Combined clinical and microbiological success (primary endpoint)

[iii] Clinical success at TOC = symptom resolution + no new uUTI symptoms

[iv] Eradication of qualifying uropathogen to <10³ CFU/mL at TOC visit

Both oral sulopenem and Augmentin® were well tolerated in this study with discontinuations due to adverse events occurring in <1% of patients on both regimens. No serious adverse events (SAE) were reported in patients receiving oral sulopenem, while five SAEs occurred in patients receiving Augmentin®, with no drug-related SAEs. The safety profile for oral sulopenem was consistent with those observed in each of the previously conducted Phase 3 trials, with no new safety signals noted beyond those associated with β-lactams.

Iterum expects to present complete results from the REASSURE trial at an upcoming scientific meeting.

"In addition to achieving non-inferiority for the primary endpoint of overall response at the TOC visit in the Augmentin®-susceptible population in the REASSURE trial, the lower limit of the 95% confidence interval around the treatment difference was above zero, indicating statistical superiority of oral sulopenem over Augmentin® for the treatment of uUTI. Furthermore, consistent results were observed for all key secondary efficacy endpoints in this population," said Sailaja Puttagunta, M.D., Iterum's Chief Medical Officer. "These results bring us one step closer to delivering a much-needed oral treatment option for women suffering from uUTIs. In addition, we believe these results, along with evidence from our prior Phase 3 studies, support the potential of sulopenem in other indications, such as complicated urinary tract infections (cUTI)."

Iterum expects to resubmit its NDA for oral sulopenem to the FDA in the second quarter of 2024. Provided that the resubmitted NDA addresses all of the deficiencies identified in the Complete Response Letter (CRL) Iterum received from the FDA in July 2021, Iterum expects that the FDA will complete its review and take action six months from the date the FDA receives the resubmitted NDA (or during the fourth quarter of 2024).