2761. Activity of Cefiderocol and Comparator Agents Against Achromobacter and Burkholderia Isolates, Collected During 2020-2022 as Part of SENTRY Antimicrobial Surveillance Program

BACKGROUND: Achromobacter and Burkholderia species are opportunistic pathogens in individuals with an immunodeficiency, most notably cystic fibrosis. Cefiderocol (CFDC) is a siderophore-conjugated cephalosporin with broad activity against Gram-negative bacteria. In this study, the activity of CFDC and comparator agents was determined against isolates of Achromobacter and Burkholderia cepacia species complex, collected in 2020–2022 in Europe and the USA as part of the SENTRY antimicrobial surveillance program. Activity of cefiderocol and comparator agents against Achromobacter and Burkholderia Isolates [Figure: see text] METHODS: Minimum inhibitory concentrations (MICs) were determined according to CLSI guidelines against 167 Achromobacter and 160 Burkholderia cepacia species complex isolates, using broth microdilution with cation-adjusted Mueller-Hinton broth (CAMHB) for comparator agents and iron-depleted CAMHB for CFDC. Comparator agents included β-lactam/β-lactamase inhibitor combinations ceftazidime-avibactam, ceftolozane-tazobactam, imipenem-relebactam, meropenem-vaborbactam, piperacillin-tazobactam, as well as meropenem, ceftazidime, levofloxacin, amikacin, trimethoprim-sulfamethoxazole, and minocycline. Susceptibility was assessed for agents with CLSI breakpoints. For agents without established CLSI breakpoints, only MIC(50), MIC(90) and MIC ranges were reported. RESULTS: CFDC was the most potent agent tested against Achromobacter, showing MIC(50) and MIC(90) values of 0.03 and 0.25 µg/mL and all isolates were inhibited at ≤4 µg/mL (Table). Isolates from cystic fibrosis patients (n=15) showed higher MIC(50) and MIC(90) values for most agents, but CFDC MIC(50) and MIC(90) values remained low (0.06 and 0.25 µg/mL, respectively). Against Burkholderia cepacia species complex, CFDC was the most potent agent tested, with MIC(50) and MIC(90) values of 0.06 and 0.5 µg/mL, and 156 out of 160 isolates inhibited at ≤4 µg/mL. None of the comparator agents showed >90% susceptibility against these isolates (Table). CONCLUSION: CFDC showed potent activity against a set of contemporary clinical Achromobacter and Burkholderia cepacia species complex isolates. These in vitro data suggest that CFDC could be an important treatment option for infections caused by these opportunistic pathogens. DISCLOSURES: Boudewijn L. DeJonge, PhD, Shionogi Inc.: Employee Sean T. Nguyen, PharmD, Shionogi: Employee|Shionogi, Inc: Employee Jason J. Bryowsky, PharmD, MS, Shionogi Inc.: Employee Christopher M. Longshaw, PhD, Shionogi BV: Employee Joshua Maher, PhD, AbbVie: Grant/Research Support|Affinity Biosensors: Grant/Research Support|AimMax Therapeutics, Inc: Grant/Research Support|Alterity Therapeutics: Grant/Research Support|Amicrobe, Inc: Grant/Research Support|Arietis Pharma: Grant/Research Support|Armata Pharmaceuticals, Inc: Grant/Research Support|Astrellas Pharma, Inc.: Grant/Research Support|Basilea Pharmaceutica AG: Grant/Research Support|Becton Dickinson And Company: Grant/Research Support|bioMerieux, Inc: Grant/Research Support|Boost Biomes: Grant/Research Support|Diamond V: Grant/Research Support|Fedora Pharmaceuticals, Inc: Grant/Research Support|Iterum Therapeutics plc: Grant/Research Support|Johnson & Johnson: Grant/Research Support|Kaleido Biosciences, Inc.: Grant/Research Support|Meiji Seika Pharma Co. Ltd.: Grant/Research Support|National Institutes of Health: Grant/Research Support|Pfizer Inc.: Grant/Research Support|Roche Holding AG: Grant/Research Support|Shionogi Inc.: Grant/Research Support|Summmit Therapeutics, Inc.: Grant/Research Support|Zoetis Inc: Grant/Research Support Rodrigo E. Mendes, PhD, AbbVie: Grant/Research Support|Basilea: Grant/Research Support|Cipla: Grant/Research Support|Entasis: Grant/Research Support|GSK: Grant/Research Support|Paratek: Grant/Research Support|Pfizer: Grant/Research Support|Shionogi: Grant/Research Support Miki Takemura, n/a, Shionogi & Co., Ltd.: Stocks/Bonds Yoshinori Yamano, PhD, Shionogi HQ: Employee