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. J Biol Res 2026, 99 (s1). https://doi.org/10.4081/jbr.2026.15421.