Molecular drivers of resistance to sulbactam-durlobactam in contemporary clinical isolates of Acinetobacter baumannii.

Samir H Moussa, Adam B Shapiro, Sarah M McLeod, Ramkumar Iyer, Nicole M Carter, Yu-Kuo Tsai, L Kristopher Siu, Alita A Miller

Antimicrobial agents and chemotherapy 2023 Nov 15

filter terms:

Acinetobacter baumannii-calcoaceticus complex (ABC) causes severe infections that are difficult to treat due to pre-existing antibiotic resistance. Sulbactam-durlobactam (SUL-DUR) is a targeted β-lactam/β-lactamase inhibitor combination antibiotic designed to treat serious infections caused by Acinetobacter, including multidrug- and carbapenem-resistant strains. In a recent global surveillance study of 5,032 ABC clinical isolates collected from 2016 to 2021, less than 2% of ABC isolates had SUL-DUR MIC values >4 µg/mL. Molecular characterization of these isolates confirmed the primary drivers of resistance are metallo-β-lactamases or penicillin-binding protein 3 (PBP3) mutations, as previously described. In addition, this study shows that certain common PBP3 variants, such as A515V, are insufficient to confer sulbactam resistance and that the efflux of durlobactam by AdeIJK is likely to play a role in a subset of strains.

Citation

Samir H Moussa, Adam B Shapiro, Sarah M McLeod, Ramkumar Iyer, Nicole M Carter, Yu-Kuo Tsai, L Kristopher Siu, Alita A Miller. Molecular drivers of resistance to sulbactam-durlobactam in contemporary clinical isolates of Acinetobacter baumannii. Antimicrobial agents and chemotherapy. 2023 Nov 15;67(11):e0066523