Transdermal lipid vesicular delivery of iloperidone: Formulation, in vitro and in vivo evaluation

The objective of present study was to develop and evaluate lipid vesicular transdermal system of iloperidone. Liposomes were prepared successfully using thin film hydration method. With aim of enhancing permeation, cholesterol from liposomes was replaced with transcutol to give PEVs. Liposomes and PEVs were evaluated for particle size, shape, entrapment efficiency, viscosity and release study. The vesicles were incorporated in 0.5% of Carbopol gel and evaluated. Particle size of liposomes and PEVs was found between 200 - 300 nm and entrapment efficiency was found 80-90%w/w. The transdermal gels were homogeneous, spreadable having acceptable pH and drug content between 90-100%.In ex vivo studies, both liposomes and PEVs showed relatively higher skin deposition and permeation of Iloperidone than the plain drug without vesicles. The in vivo pharmacokinetics studies showed relative bioavailability of the PEV loaded gel as 62% and 166% when compared to the oral drug and gel without vesicles respectively. Pharmacodynamic studies showed FRT and HRT delay responses of the transdermal gel systems were significant[p < 0.05] as compared to control at the end of 24 hs. Thus, it can be concluded that transdermal delivery system can be a promising approach for sustained delivery of Iloperidone.