Earlier this month, Acurx Pharmaceuticals announced efficacy results from their phase 2 clinical trial of an investigational antibiotic, ibezapolstat, for the treatment of C difficile Infection (CDI).
Specifically, in 26 ibezapolstat-treated patients in phases 2a and 2b, the clinical cure rate was 96%, and the investigators reached their objective of assessing the primary efficacy endpoint after 10 days of oral treatment.
The completed phase 2a segment was an open label cohort of up to 20 subjects from study centers in the United States. In this cohort, 10 patients with diarrhea caused by C difficile were treated with ibezapolstat 450 mg orally, twice daily for 10 days. All patients were followed for recurrence for 28± 2 days. Per protocol, after 10 patients of the projected 20 phase 2a patients completed treatment (100% cured infection at end of treatment), the trial oversight committee assessed the safety and tolerability and made its recommendation regarding early termination of the phase 2a study and advancement to the phase 2b segment.
Acurx had previously announced that it decided to terminate the phase 2b vancomycin-controlled trial segment early based on aggregate blinded data showing a high observed clinical cure rate with no emerging safety concerns.
What You Need to Know
The investigational antibiotic, ibezapolstat, developed by Acurx Pharmaceuticals, has demonstrated a 96% clinical cure rate in patients with Clostridioides difficile infection (CDI) in a small trial.
The study reported that ibezapolstat was well tolerated, with no drug-related serious adverse events. Only 3 patients experienced mild adverse events related to the drug, all of which were gastrointestinal in nature and resolved without treatment.
Ibezapolstat represents a novel approach in CDI treatment as it is reported to be the first antibiotic candidate designed to work by blocking the Pol IIIC enzyme in C difficile.
"I am very encouraged by the accumulating data showing that ibezapolstat is clinically comparable to vancomycin in treating CDI,” Stuart Johnson, MD, professor of Medicine, Loyola University, and Acurx Scientific Advisory board member, said in a statement. “Since there is only one other antibiotic besides vancomycin approved for treatment of this serious disease, there is a clear need for more first-line therapeutic agents in our armamentarium.”
The company also reported ibezapolstat was well tolerated and there were no drug-related serious adverse events. Three patients experienced 1 mild adverse event assessed by the blinded investigator to be drug-related. All 3 events were gastrointestinal in nature and resolved without treatment. There were no drug-related treatment withdrawals or no drug-related serious adverse events.
Ibezapolstat is reported to be the first antibiotic candidate intended to work by blocking the Pol IIIC enzyme in C difficile.This therapy is a first-in-class of a new class of Pol IIIC inhibitors. In June 2018, the antibiotic was designated by the FDA as a Qualified Infectious Disease Product (QIDP) for the treatment of patients with CDI and deemed eligible to benefit from the incentives for the development of new antibiotics established under the Generating New Antibiotic Incentives Now (GAIN) Act. The following year, the FDA granted the therapy a “Fast Track" designation.
In a previous interview with Contagion, Kevin Garey, PharmD, chair of the Department of Clinical Sciences and Administration and professor of Pharmacy Practice at the University of Houston College of Pharmacy made note of the differing development trend of antibiotics for this health care-associated infection. “A lot of the drug development now within C diff antibiotics is, ‘will my new compound—ibezapolstat in this case—prevent disruption to the microbiome more favorable to the comparator’ usually vancomycin,” Garey stated.
Acurx is a clinical stage biopharmaceutical company developing a new class of small molecule antibiotics for difficult-to-treat bacterial infections.
Acurx Announces Positive Top-Line Ibezapolstat Phase 2 Efficacy Results with 96% Clinical Cure Rate in Patients with C. difficile Infection Acurx Pharmaceuticals press release. November 2, 2023. Accessed November 19, 2023. https://www.acurxpharma.com/news-media/press-releases/detail/66/acurx-announces-positive-top-line-ibezapolstat-phase-2