Abstract

Background: Nanotechnology has provided substantial benefits in drug delivery, especially in the treatment of dermatological diseases. Psoriasis is a chronic inflammatory skin disease in which topical delivery of antipsoriatic agents is considered the first line treatment.

Objective: To investigate whether the encapsulation of the synthetic retinoid tazarotene in a nanocarrier based on jojoba oil would decrease its irritation potential and clinically improve its therapeutic outcome in psoriatic patients.

Method: A microemulsion system based on jojoba wax and labrasol/plurol isostearique was prepared and characterized.

Results: The selected formula displayed spherical morphology, particle size of 15.49±2.41 nm, polydispersity index of 0.20 ±0.08, negative charge and low viscosity. The microemulsion provided two folds increase in skin deposition of tazarotene, correlating with higher reduction in psoriatic patients PASI scores after treatment (68% reduction in PASI scores versus 8.96% reduction with the marketed gel). No irritation was encountered in patients using microemulsion, with redness and inflammation reported with the marketed gel-treated patients.

Conclusion: Jojoba oil microemulsion proved to be advantageous in reducing the irritancy of tazarotene, enhancing its skin deposition and achieving better therapeutic outcome in psoriatic patients.

Keywords: Ex-vivo deposition, jojoba oil, microemulsion, pseudoternary phase diagram, psoriasis, tazarotene.

Graphical Abstract