Acurx Pharmaceuticals (NASDAQ:ACXP) executives used the company’s fourth-quarter and full-year 2025 earnings call to highlight a new clinical program for ibezapolstat in recurrent C. difficile infection (rCDI), recent scientific and intellectual property milestones, and year-over-year reductions in operating expenses. Management also detailed the company’s year-end cash position and recent financing activity.
Clinical and R&D updates: recurrent CDI trial program
President and CEO David Luci said the company is launching what it described as a “groundbreaking” ibezapolstat clinical trial program in patients with recurrent CDI, following phase II results in acute CDI. Luci reiterated that in the phase II trial, ibezapolstat achieved a 96% clinical cure rate in 26 patients, and that among patients who achieved clinical cure, none experienced a recurrence in follow-up. He added that all 25 clinically cured patients were recurrence-free one month after treatment, and that five of five patients followed for three months remained recurrence-free.
During the Q&A, Medical Director Michael Silverman provided additional details on trial design. He said the primary assessment endpoint for recurrence will be eight weeks after cure, citing precedent from other products approved for prevention of recurrent disease. He added that Acurx expects to continue following patients for approximately six months after the end of therapy to collect additional data.
Silverman also said the rCDI study will use a 14-day treatment period, longer than the 10-day duration typically used in prior CDI trials. He said the longer course is based on prior work suggesting a longer treatment period for the acute episode may increase cure rates, yielding a more robust sample to evaluate recurrence.
Timing and cost expectations
Management estimated the open-label rCDI pilot trial would cost about $4 million to $5 million. Luci said the company expects to begin enrolling in the second half of 2026, and that full enrollment would likely take about 12 to 15 months, depending on site performance. In response to questions about whether the company might move more quickly into phase III, management said it may review an initial subset of patients but emphasized the value of completing the 20-patient dataset for sizing and decision-making.
Silverman said the company does not yet have treatment data for ibezapolstat in the multiple-recurrent population, and therefore does not know the true effect size. Based on assumptions informed by prior phase II experience in a different patient population, he said Acurx is currently projecting a single phase III trial in rCDI could require roughly 360 to 400 patients.
Management also discussed the FDA’s recent statements suggesting a move toward a “one trial” default standard for registration and the potential implications for Acurx’s broader CDI program. Executive Chairman Robert DeLuccia said the company is encouraged by the development but believes the agency still needs to formalize the approach through guidance. DeLuccia noted that Acurx had previously planned a roughly 474-patient non-inferiority trial versus vancomycin for broader CDI and said the company could consider increasing the size to support a safety database if only one pivotal trial is required.
Scientific publications, pipeline data, and patents
On recent scientific progress, Luci highlighted Acurx’s presentation at IDWeek in October, where the company discussed ibezapolstat’s microbiome-sparing properties and presented new colonic microbiome data from a mouse infection model. According to Luci, Dr. Kevin Garey of the University of Houston, a principal investigator in microbiology and microbiome aspects of the program, said initial work on lead DNA Pol IIIC inhibitor compounds indicates microbiome-sparing effects observed with ibezapolstat may be a class effect. Luci said Garey also pointed to data suggesting a low probability for DNA Pol IIIC inhibitors to increase the risk of causing CDI, vancomycin-resistant Enterococcus, or other gut microbiome-related infections.
Luci also noted that Nature Communications published results from a collaboration with Leiden University Medical Center demonstrating structural biology research showing ibezapolstat bound to its target. The paper is titled “A Unique Inhibitor Conformation Selectively Targets the DNA Polymerase Pol IIIC of Gram-Positive Priority Pathogens.” Management characterized the publication as a milestone that supports rational development of this antimicrobial class against other Gram-positive priority pathogens.
In addition, Luci said the U.S. Patent and Trademark Office granted a new patent in February 2026 covering composition of matter and method of use for Pol IIIC inhibitors, extending to December 2039, subject to potential extension under U.S. patent rules.
Funding, manufacturing, and government discussions
Management said it continues to pursue funding opportunities for phase III clinical trial programs and to consider alternative financial pathways. In the Q&A, Luci said Acurx has ongoing discussions with government agencies, including BARDA, and that U.S.-based manufacturing is viewed as important in the context of potential public-private partnerships.
DeLuccia added that ibezapolstat and DNA Pol IIIC inhibitors may be well-suited to stockpiling due to stability. He said the company has about 48 months of stability data for ibezapolstat active pharmaceutical ingredient (API), potentially approaching five years, with similar long-term stability for packaged product. DeLuccia also said that ibezapolstat’s commercial supply chain for API and packaged product will be “made in America.”
Financial results: reduced expenses and higher year-end cash
Chief Financial Officer Rob Shawah reported that Acurx ended 2025 with $7.6 million in cash, up from $3.7 million at the end of 2024. He said the company raised approximately $1.5 million of gross proceeds during the fourth quarter through purchases under its equity line of credit (ELOC), and about $4.0 million of gross proceeds under the ELOC for the full year. Luci also noted the execution of 170,000 Series F warrants in October that generated approximately $1.4 million in gross proceeds. Shawah later added that Acurx had about $7 million to $8 million remaining under its ELOC.
Operating expenses declined year over year. Research and development expense was $0.3 million for the fourth quarter of 2025, compared with $0.8 million in the prior-year quarter, which Shawah attributed primarily to lower manufacturing and consulting costs as prior-year trial-related expenses rolled off. For the full year, R&D expense was $1.8 million versus $5.4 million in 2024, driven by reduced manufacturing-related and consulting costs tied to earlier phase IIb and phase III preparation efforts.
General and administrative expense was $1.3 million for the fourth quarter, down from $2.0 million a year earlier, reflecting lower compensation-related costs and professional fees. For the year, G&A expense was $6.3 million compared with $8.7 million in 2024, primarily due to lower professional fees, reduced share-based compensation, and lower compensation costs, partially offset by higher legal costs.
Acurx reported a fourth-quarter net loss of $1.6 million, or $0.73 per diluted share, compared with a net loss of $2.8 million, or $3.29 per diluted share, in the fourth quarter of 2024. For the full year, net loss was $8.0 million, or $5.32 per diluted share, compared with a net loss of $14.1 million, or $17.45 per share, in 2024. Shawah said Acurx had 2,348,113 shares outstanding as of December 31, 2025.
About Acurx Pharmaceuticals (NASDAQ:ACXP)
Acurx Pharmaceuticals, Inc, headquartered in King of Prussia, Pennsylvania, is a clinical‐stage biopharmaceutical company focused on the discovery and development of novel anti‐infective therapies. The company’s research platform leverages insights into bacterial virulence regulation and quorum sensing pathways to design small-molecule candidates aimed at reducing pathogen toxicity and biofilm formation. By targeting key mechanisms of infection rather than bacterial viability alone, Acurx seeks to offer differentiated treatment options that may help address the growing challenge of antibiotic resistance.
Acurx’s lead product candidates are being developed to treat acute bacterial skin and skin structure infections (ABSSSI), including cases caused by drug-resistant strains such as methicillin-resistant Staphylococcus aureus (MRSA).
