2026. 169 | Microbiological resistance and clinical ineffectiveness: an investigation into amoxicillin and amoxicillin/clavulanate efficacy in real-world populations: Pierangela Irrera1, Gabriella Frattima1, Fabiola De Luca1, Anna Paola Capra1, Michela Campolo1, Alessio Ardizzone2, Emanuela Esposito1 | 1Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Italy; 2UniCamillus-Saint Camillus International University of Health Sciences, Rome, Italy. Journal of Biological Research - Bollettino della Società Italiana di Biologia Sperimentale. 99, s1 (Mar. 2026). DOI:https://doi.org/10.4081/jbr.2026.15421.