Acurx Pharmaceuticals announced on October 9, 2025, that the Australian Patent Office has granted the company a new patent covering DNA Polymerase IIIC inhibitors, including compositions-of-matter. This latest patent approval expands Acurx's international intellectual property portfolio, bringing the total to seven patents across multiple jurisdictions for its ACX-375C program.
The Staten Island-based late-stage biopharmaceutical company has now secured patent protection in the United States (three patents), Israel, Japan, India, and Australia, with additional country-level filings currently in process. These patents protect Acurx's proprietary antimicrobial technologies focused on DNA Polymerase IIIC inhibitors.
Novel Mechanism Targets Resistant Pathogens
Acurx's approach centers on developing antibiotic candidates with a Gram-positive selective spectrum (GPSS®) that specifically blocks the active site of the Gram-positive bacterial enzyme DNA polymerase IIIC (pol IIIC). This mechanism inhibits DNA replication and leads to Gram-positive bacterial cell death.
Robert J. DeLuccia, Executive Chairman of Acurx, emphasized the significance of the patent expansion: "Achieving this patent in Australia adds to our growing number of countries where we are patent protected for a long period of time as we further develop our innovative, AI-supported drug discovery platform of second-generation DNA pol IIIC inhibitors."
The company's R&D pipeline targets several challenging Gram-positive bacteria, including Clostridioides difficile, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), drug-resistant Streptococcus pneumoniae (DRSP), and B. anthracis (anthrax), which is classified as a Bioterrorism Category A Threat-Level pathogen.
Lead Compound Advances Toward Phase 3
Acurx's lead product candidate, ibezapolstat, is Phase 3-ready for the oral treatment of C. difficile infection. The company has plans in progress to begin international clinical trials as soon as possible. DeLuccia noted that this lead compound "has validated the bacterial target for DNA pol IIIC inhibitors."
The company's preclinical pipeline includes systemically absorbed compounds designed for both oral and parenteral administration. These second-generation inhibitors are being developed for multiple clinical applications, including acute bacterial skin and skin-structure infections (ABSSSI, including MRSA), community-acquired bacterial pneumonia (CABP), hospital and/or ventilator-associated bacterial pneumonia (HABP/VABP), bacteremia with or without sepsis and/or infectious endocarditis, bone/joint infections, prosthetic joint infections, and inhalational anthrax.
Transformative Treatment Potential
DeLuccia expressed confidence in the platform's potential impact: "We believe these new compounds have potential to transform the antibiotic treatment paradigm to combat multidrug-resistant Gram-positive pathogens such as Staphylococcus aureus, including MRSA, VRE, and PRSP; furthermore, these compounds are expected to be active against B. anthracis or anthrax."
The company's preclinical pipeline specifically includes development of an oral product candidate for ABSSSI treatment, with a parallel development program for inhaled anthrax treatment being planned simultaneously.
Acurx's AI-supported drug discovery platform represents a novel approach to antibiotic development, focusing on second-generation DNA pol IIIC inhibitors that could address the growing challenge of antimicrobial resistance in Gram-positive bacterial infections.
