RESUMO
Adapalene is used for treatment of acne vulgaris, a common dermatological disease. Nano-based carriers have been developed to improve solubility and bioavailability of adapalene and other acne treatment drugs. In our previous report, tea tree oil nanoemulsion containing adapalene gel (TTO NE + ADA Gel) showed appropriate physical and biological properties such as stability, viscosity, pH, size, morphology and biocompatibility in an animal model. The present study was designed to assess efficacy and safety of the TTO NE + ADA Gel in comparison with 0.1% adapalene marketed gel (ADA Marketed Gel). A total of 100 patients were randomized to receive TTO NE + ADA Gel or ADA Marketed Gel, once daily at night, for 12 weeks. Analysis for efficacy was conducted by acne lesion count (total, inflammatory and non-inflammatory) and acne severity index at weeks 4, 8 and 12 using generalized estimating equation along with the safety assessments in each measurement for assessing dryness, erythema, burning sensation and irritation. Significantly better reduction in total, inflammatory, and non-inflammatory acne lesions were reported for TTO NE + ADA Gel as compared to the ADA Marketed Gel overall and on each measurement occasion (p value < 0.001 for all). Mean acne severity index also reduced with TTO NE + ADA Gel significantly in comparison with ADA Marketed Gel (p value < 0.001). Dryness was the most common adverse effect reported in both groups and it was higher in TTO NE + ADA Gel group. In conclusion, TTO NE + ADA Gel compared to ADA Marketed Gel appears more effective in the treatment of acne vulgaris, with no important change in adverse effects.