New York-based Acurx Pharmaceuticals (Nasdaq: ACXP) and Leiden University Medical Center have launched a structural biology collaboration aimed at resolving the first three-dimensional structure of methicillin-resistant Staphylococcus aureus DNA polymerase IIIC in complex with DNA and an Acurx inhibitor, potentially providing a structural basis for designing a new class of antibiotics against drug-resistant Gram-positive pathogens.
The collaboration centers on Acurx's DNA pol IIIC inhibitor platform, including ibezapolstat, a small-molecule antibiotic that completed Phase II trials for C. difficile infection (CDI) and is described by the company as Phase III-ready pending financing. PolC is a replicative DNA polymerase present in Gram-positive bacteria but absent in humans and Gram-negative organisms. Prior LUMC structural work, published in Nature Communications in 2025, resolved three PolC complexes from Enterococcus using cryo-electron microscopy at 3.2 angstrom resolution; the new partnership extends that effort to the MRSA PolC isoform, for which no inhibitor-bound structural data currently exist, according to the company.
Financial terms were not disclosed. LUMC will conduct the structural biology research under the lead of Wiep Klaas Smits, PhD, in collaboration with Meindert Lamers, PhD, and Mia Urem, PhD; Acurx contributes its proprietary inhibitor compounds and co-directs the research agenda. No licensing, asset transfer, or clinical development obligations are described in the agreement.