Development and characterization of oral lipid-based Amphotericin B formulations with enhanced drug solubility, stability and antifungal activity in rats infected with Aspergillus fumigatus or Candida albicans
SEDDS formulations were prepared by simple mixing at 40 °C. Peceol/DSPE-PEG-lipid formulations were prepared by solvent evaporation. Parameters evaluated included: miscibility, solubility and emulsion droplet size after incubation in simulated gastric fluid (SGF) or simulated intestinal fluid (SIF) via dynamic light scattering. The stability of AmpB in Peceol/DSPE-PEG was evaluated in SGF and SIF. Phase stability of AmpB in Peceol ± DSPE-PEG following thermal cycling was evaluated by atomic force microscopy (AFM). Aspergillus fumigatus (2.9–3.45 × 107 colony forming units per mL [CFU]) or Candida albicans (3–3.65 × 106 CFU per mL) were injected via the jugular vein; 48 h later male albino Sprague–Dawley rats (350–400 g) were administered either a single oral gavage of a Peceol®-DSPE/PEG2000-based AmpB (10 mg AmpB/kg and 5 mg AmpB/kg for the Candida albicans study only) twice daily for 2 consecutive days, a single intravenous (i.v.) dose of Abelcet® (5 mg AmpB/kg), or physiologic saline (non-treated controls; n = 9) once daily for 2 consecutive days. Antifungal activity was assessed by organ CFU concentrations and plasma galactomannan levels in the case of A. fumigatus and organ CFU concentrations in the case of Candida albicans. Plasma samples were taken from each animal prior to infection, 48 h after initiation of infection but prior to drug treatment and at the end of the study for plasma creatinine determinations as a measure of renal toxicity.