Efficacy and safety of a nano-emulsion gel formulation of adapalene 0.1% and clindamycin 1% combination in acne vulgaris: a randomized, open label, active-controlled, multicentric, phase IV clinical trial.

Background: Acne vulgaris is a very common skin disease with a significant detrimental effect on the quality of life of the patients.

Aims: To assess the comparative efficacy and safety of a nano-emulsion gel formulation of adapalene and clindamycin combination with its conventional formulation in the treatment of acne vulgaris of the face. It was a prospective, randomized, open label, active-controlled, multicentric, clinical trial.

Methods: Eligible patients suffering from acne vulgaris of the face were randomized to receive once-daily treatment with a nano-emulsion gel or conventional gel formulation of adapalene 0.1% and clindamycin (as phosphate) 1% combination for 12 weeks. Total, inflammatory and noninflammatory lesion counts, with grading of acne severity were carried out on a monthly basis. Safety assessments were done to determine the comparative local and systemic tolerability. Two-tailed significance testing was carried out with appropriate statistical tests, and P-values < 0.05 were considered as significant.

Results: 209/212 patients enrolled in the study were eligible for efficacy and safety assessments in both nano-emulsion gel (118/119 patients) and conventional gel (91/93 patients) groups. Significantly better reductions in total (79.7% vs. 62.7%), inflammatory (88.7% vs. 71.4%) and noninflammatory (74.9% vs. 58.4%) lesions were reported with the nano-emulsion gel as compared to the conventional gel (P < 0.001 for all). Mean acne severity score also reduced significantly more with the nano-emulsion formulation (1.9 ± 0.9 vs. 1.4 ± 1.0; P < 0.001) than the comparator. Significantly lower incidence and lesser intensity of adverse events like local irritation (4.2% vs. 19.8%; P < 0.05) and erythema (0.8% vs. 9.9%; P < 0.05) were recorded with the nano-emulsion gel.

Conclusions: The nano-emulsion gel formulation of adapalene and clindamycin combination appears to be more efficacious and better tolerated than the conventional formulation for the treatment of acne vulgaris in Indian patients. Further studies can elucidate the comparative treatment benefits of this nano-emulsion gel formulation.