Clinical Efficacy and Safety of a Novel Antifungal, Fosmanogepix, in Patients with Candidemia Caused by Candida auris: Results from a Phase 2 Trial

Fosmanogepix (FMGX), a novel antifungal available in intravenous (IV) and oral formulations, has broad-spectrum activity against pathogenic yeasts and molds, including fungi resistant to standard of care antifungals. This multicenter, open-label, single-arm study evaluated FMGX safety and efficacy for treatment of candidemia and/or invasive candidiasis caused by Candida auris. Eligible participants were ≥18 years, with established candidemia and/or invasive candidiasis caused by C. auris, (cultured within 120 h [for candidemia] or 168 h [for invasive candidiasis without candidemia] with accompanying clinical signs) and limited treatment options. Participants were treated with FMGX (≤42 days; loading dose: 1000 mg IV twice daily [Day 1], followed by 600 mg IV once daily [QD]). Switching to oral FMGX 800 mg QD was permitted from Day 4. Primary endpoint was treatment success (survival and clearance of C. auris from blood/tissue cultures without additional antifungals) at the end of the study treatment (EOST), assessed by an independent data review committee (DRC). Day 30 survival was a secondary endpoint. In vitro susceptibility of Candida isolates was assessed. Nine participants with candidemia (male:6, female:3; 21 to 76 years) in intensive care units in South Africa were enrolled; all received IV FMGX only. DRC-assessed treatment success at EOST and Day 30 survival were 89% (8/9). No treatment related adverse events or study drug discontinuations were reported. FMGX demonstrated potent in vitro activity against all C. auris isolates (MIC range: 0.008 to 0.015 μg/mL [CLSI]; 0.004–0.03 μg/mL [EUCAST]), with the lowest MICs compared to other antifungals tested. Thus, the results showed that FMGX was safe, well-tolerated, and efficacious in participants with candidemia caused by C. auris.