The objective of the study is to investigate the efficacy and the safety of NAI-Acne 3% gel in patients with moderate to severe facial acne applying the investigational product for 12 weeks in comparison with placebo. Efficacy of the NAI-Acne gel will be evaluated in terms of absolute and percent change in inflammatory lesion count (ILC), score reduction after investigator’s global assessment (IGA), absolute and percent change in total lesion count (TLC) and change in Cardiff acne disability index (CADI).