A Randomized, Double-blind Controlled Clinical Study to Evaluate the Efficacy and Safety of Minoxidil Topical 2% Nanosuspension with Aqueous Base in the Treatment of Androgenetic Alopecia Areata

Background and Purpose: Using the commercially manufactured forms of minoxidil, the only approved topical drug preparation for hair regrowth in patients with androgenetic alopecia (AGA) comes across with challenges such as limited permeation through the superficial layers of the skin to reach the site of action and topical adverse reactions like itching and inflammation occur because of the ethanol in the formulations. In this study, a novel nanosuspension formulation with an aqueous base was prepared and evaluated to overcome the discussed challenges. 
Materials and Methods: The nanosuspension formulation was characterized by size, zeta potential, morphology, and in vitro release. Seventy patients were subjected to use either 1 mL of nanosuspension or the commercial product twice daily for six months and were then examined for changes in hair follicle diameter and hair density within a 1 × 1-cm2 area of the scalp as the primary endpoints besides any adverse reaction manifestation as the secondary endpoint.
Results: The nanosuspension formulation showed uniform morphology, 200-nm particle size, and suitable zeta potential that ensures the stability. The in vitro release study exhibited almost 90% release in the first 6 h. It was observed that there were no significant differences between the efficacy of aqueous-based topical 2% nanosuspension of minoxidil and the commercial product in the treatment of AGA (P > 0.05). However, the aqueous-based topical 2% nanosuspension formulation showed better safety and tolerability compared to the marketed profile. 
Conclusions: It could be concluded that aqueous-based topical 2% nanosuspension is a suitable form with enhanced patient compliance compared to commercially manufactured products.