Evaluation of topical econazole nitrate formulations with potential for treating Raynaud's phenomenon

The purpose of this work was to design and characterize a topical formulation of econazole nitrate (EN) with potential for treating Raynaud's phenomenon (RP). Four topical dosage forms (F1_topical solution, F2_HPMC or hydroxypropyl methylcellulose dispersion, F3_VersaBase^® cream, and F4_{_}Lipoderm^® Activemax™ Cream) containing 3% w/w EN were prepared and characterized for drug content, pH, viscosity, spreadability, drug crystallinity, stability, and in vitro permeation using Franz cells across pig ear skin, and results were compared to the 1% marketed EN cream. All four formulations had acceptable physical and visual characteristics required for topical application, with 3% w/w EN. The order of amount of drug permeated from highest to lowest was F2 (10.27%) > F4 (2.47%) > F1 (2.28%) > F3 (1.47%) > marketed formulation (0.22%). Formulation F2 showed better penetration of the drug into the stratum corneum, epidermis, and dermis layers. The drug concentration in the stratum corneum and epidermis was approximately 10-20 times higher with F2 compared to the marketed formulation. All formulations were found to be stable for up to 6 months. All four EN formulations were found to be better than the 1% marketed cream. Formulation F2_{_}HPMC dispersion could be further explored as a treatment option for RP.