Transdermal delivery of Etoricoxib through ethosomal formulation: An ingenious approach towards treatment of skin inflammation

- An ethosomal formulation of ET and CD complex for treatment of skin inflammation.
- Maintained drug concentration in blood serum.
- Deeper skin layer penetration ability of the ethosomal formulation.
- Minimal change in residual drug content after 90 days.

Etoricoxib (ET) based formulations viz. physical mixture of ET with β-cyclodextrin (CD); ethosomal formulation of ET and CD complex (DCE); and ET are investigated against skin inflammation. These formulations are characterized using XRD, SEM, TEM and DSC, revealed the amorphous nature of DCE (particle size 0.3-0.4 μm). ET with ethosome (PDE) and ET, CD with ethosome (DCE) is prepared using varied concentrations of lecithin and ethanol; demonstrated entrapment efficiencies of 70.8 ± 4.4% and 77.5 ± 4.2% for PDE-8 and DCE-8 respectively. Kneaded complex (KC) exhibited 77.96% and 75.32% drug release in 30 min in PBS pH 7.4 and 5.5 respectively. In-vitro and ex-vivo drug permeation in phosphate buffer saline (PBS) revealed 63-82% ET permeation for DCE-8; while in rat serum DCE-8 produced higher plasma concentration of ET (3.26 ± 0.25 μg/ml) within 8 h that is maintained over 24 h. The percentage inhibition of carrageenan induced paw edema, 8 h after applying DCE-8 is found to be 77.74% higher than PDE-8 (54.1%) and one more formulation which is a mixture of ET and ethanol in proper proportion (CPD) (20.04%). Stability studies indicated that DCE-8 stored at 5 ± 3 °C shows <5% change in residual drug content after 90 days. Present work clearly demonstrates that the tailor-made formulation DCE-8 may exhibit potentiality towards transdermal delivery of ET in the treatment of skin inflammation.

Ex-vivo studies performed on Etoricoxib: β-cyclodextrin complex ethosomal formulation revealed improved skin penetration and ability of the complex to maintain the constant drug concentration over 24 h in rat serum.260