Formation of spherical micelles composed of the novel platelet activating factor receptor antagonist, E5880

The injectable formulation of E5880, a novel platelet activating factor (PAF) receptor antagonist, was developed. The physicochemical properties of E5880 micelles in the optimized formulation (0.6 mg/mL of E5880, 0.1% of citric acid, 10% lactose, pH 2.8) were characterized. The critical micelle concentration of E5880 was 0.09 mg/mL, and the structure was spherical. The micelle size was 5.6 nm. The number of molecules per micelle was 46. The micropolarity around the hydrocarbon region in the micelle was similar to that of isobutanol.