1076. Activity of Rezafungin and Comparator Antifungal Agents Tested Against a Worldwide Collection of Contemporaneous Invasive Fungal Isolates (2019-2020)

Abstract Background Rezafungin (RZF) is a new echinocandin (ECH) with long half-life and front-loaded drug exposure that allow for once-weekly intravenous administration. RZF under Phase 3 development the treatment of candidemia invasive candidiasis prevention fungal disease caused by Candida, Aspergillus, Pneumocystis spp. in blood marrow transplant recipients. We evaluated activity comparators against isolates from SENTRY Antimicrobial Surveillance Program. Methods A total 1,427 Candida spp., 38 Cryptococcus neoformans (CNEO), 186 Aspergillus fumigatus (AFM), 28 section Flavi (AFL) collected 24 countries 2019-2020 were tested. CLSI antifungal broth microdilution assays performed according to standard method (M27, M38) exception panels made dispensing 10 µL 20x stock solution into contained 90 RPMI mixing. criteria applied (M59, M60, M61). Results demonstrated potent C. albicans (CA; MIC50/90, 0.03/0.06 mg/L), tropicalis (CT; glabrata (CG; 0.06/0.06 krusei (CK; 0.03/0.03 dubliniensis (MIC50/90, 0.06/0.12 mg/L). inhibited 99.6% parapsilosis (CP; MIC50/90,1/2 mg/L) at ≤2 mg/L. was similar other ECH these 6 All CA, CT, CK as well majority CG (96.2-97.9%) CP (86.2-100%) susceptible (S) comparator ECHs. Fluconazole resistance detected among 0.5%, 4.5%, 10.5%, 1.2% CG, CP, respectively. The azoles active CNEO, but all ECHs displayed limited CNEO. AFM (MEC90 range, 0.015-0.06 AFL 0.015-0.03 16 (8.6%) S voriconazole, 100% wild-type mould-active azoles. Conclusion infections. These vitro results support disease. Disclosures Cecilia G. Carvalhaes, MD, PhD, AbbVie (formerly Allergan) (Research Grant or Support)Cidara Therapeutics, Inc. Support)Cipla Therapeutics USA Support)Melinta LLC Support)Pfizer, Support) Abby L. Klauer, n/a, Cidara Support)Spero Paul R Rhomberg, Michael Pfaller, Basilea Pharmaceutica International, Ltd. Support)Department Health Human Services Support, Contract no. HHSO100201600002C)Pfizer, Mariana Castanheira, Support)Bravos Biosciences Support)GlaxoSmithKline Support)Qpex Biopharma Support)Shionogi Affinity Biosensors (Individual(s) Involved: Self): Research Support; Allergan Amicrobe, Inc Amplyx Pharma Artugen USA, Astellas Beth Israel Deaconess Medical Center BIDMC bioMerieux BioVersys Ag Bugworks Cipla Contrafect Cormedix Crestone, Curza CXC7 Entasis Fedora Pharmaceutical Fimbrion Fox Chase GlaxoSmithKline Guardian Hardy Diagnostics IHMA Janssen & Development Johnson Kaleido Biosceinces KBP Luminex Matrivax Mayo Clinic Medpace Meiji Seika Co., Melinta Menarini Merck Meridian Bioscience Micromyx MicuRx N8 Nabriva National Institutes University Singapore North Bristol NHS Trust Novome Biotechnologies Paratek Pfizer Prokaryotics QPEX Rhode Island Hospital RIHML Roche Roivant Salvat Scynexis SeLux Shionogi Specific Spero SuperTrans LT T2 Biosystems Queensland Thermo Fisher Scientific Tufts Universite de Sherbrooke Iowa Hospitals Clinics Wisconsin UNT System College Pharmacy URMC UT Southwestern VenatoRx Viosera Wayne State Support