Engineered triamcinolone acetonide loaded glycerosomes as a novel ear delivery system for the treatment of otitis media

Abstract

Ear-oriented therapeutics vehiculation strategies are requisites for effective treatment of various otic ailments including otitis media (OM). Conquering minimal permeability of the intrinsic barrier of middle ear; intact tympanic membrane (TM) is still a defiance. In this study, the fabrication of glycerosomes was explored to boost triamcinolone acetonide (TA) delivery to the middle ear via the otic application to improve treatment of OM. Opting a d-optimal design, TA glycerosomes were formulated and optimized using ethanol injection method. The optimized formula was assessed for morphology, viscosity, ex vivo TM permeation and deposition and physical stability. Moreover, OM induction in rats using lipopolysaccharides was conducted, histological and biochemical investigations were performed to assess the therapeutic potential of TA glycerosomes and their tolerability as well. The optimized formula displayed a nanosized value (106.1 ± 2.82), low polydispersity index (0.079 ± 0.04), satisfactory drug entrapment efficiency (80.62 ± 4.41 %), shear thinning behavior and excellent physical stability. Ex-vivo TM permeation and deposition monitoring for 24 h demonstrated greater flux and deposition compared to free drug. More importantly, the in vivo studies demonstrated the supremacy of glycerosomes with respect to tolerability and efficacy in alleviating OM following ototopical application compared to marketed drug. Such therapeutic modality represents a promising option to boost the efficacy of otic drugs, awaiting clinical translation.