Miconazole Nitrate loaded Soluplus®-Pluronic® nano-micelles as promising Drug Delivery Systems for Ocular Fungal Infections: In vitro and In vivo Considerations

Miconazole nitrate (MN) is a broad-spectrum antifungal agent which suffers poor solubility and impermeability to the ocular tissue which limits its use in the treatment of ocular infections especially fungal keratitis, which is considered one of the most prevailing ocular infections. The current study aims to utilize polymeric mixed nano-micelles for the ocular delivery of MN using 33 full factorial design by varying the ratios of Pluronic® P123, Pluronic® F127, and Tetronic® T701 while the monitored responses were particle size, cloud point (CP), encapsulation efficiency (%EE) and %released at 6 hours (%Q6) at pH 7.4. The optimized formula was incorporated with Soluplus® (SP) to further enhance the (%EE) and the resultant formula was assessed in vitro as well as in vivo against C. albicans in treatment of induced ocular candidiasis using rabbits as a model animal. Results revealed that the optimized formula which comprised F127 and P123 in a ratio of (2:1) when incorporated with SP (SP-MPM) resulted in an increase in %EE from 35.12±3.18 to 99.19±7.03 with a particle size of 44.39±2.68nm with a sustained release profile and stability for 3 months at 4±2°C. In vivo results demonstrated the enhanced ability of SP-MPM for treatment of ocular candidiasis with enhanced % inhibition and susceptibility to C. albicans compared to 0.2% MN suspension confirmed with histopathological examination of rabbit’s eyes after 7 days of treatment with the absence of any degenerative effect to the ocular tissue. Thus, it can be concluded that SP-pluronic mixed nano-micelles offer a successful and stable ocular delivery platform for antifungal drug MN ensuring both its safety and efficacy.