Acurx is initiating an open-label pilot trial enrolling up to 20 patients with at least two C. difficile infection recurrences within the past 12 months to evaluate ibezapolstat’s ability to prevent further infections. Trial startup activities begin this month, with the first patient expected to enroll in the fourth quarter of 2026.

In a Phase 2 study, ibezapolstat achieved a 96% clinical cure rate in 26 acute CDI patients, with zero recurrences at one and three months, while sparing beneficial gut microbiota. Unpublished laboratory results indicate that protective bacterial taxa persist post-treatment, supporting the drug’s potential to prevent recurrence.

The program holds FDA QIDP and Fast-Track designations and EMA SME status, positioning it for accelerated review. Following the pilot, Acurx plans an active-controlled Phase 3 registration trial and aims to seek approval under the FDA’s Limited Population Pathway, potentially leveraging a new one-trial default standard for registration.

C. difficile infection affects about 500,000 U.S. patients annually, with 30,000 deaths and a $5 billion cost burden, $2.8 billion of which stems from recurrences. Acurx will discuss funding needs for international Phase 3 studies on its March 13 earnings call, where management will provide further program details.