Antioxidants are becoming increasingly important in the treatment of skin disease. In addition to their known anti-inflammatory effects, antioxidants may act to prevent the oxidation of sebum which has been proposed to be comedogenic in acne patients. Sodium L-ascorbyl-2-phosphate (APS) is a stable vitamin C derivative and highly effective antioxidant that has demonstrated efficacy in acne in open label studies. Objective To evaluate the efficacy and safety of APS 5% lotion for the treatment of acne in a blinded controlled study. Methods A total of 50 subjects were randomized in a double-blind controlled trial to receive APS 5% lotion or vehicle for 12 weeks. Evaluation included an Investigator’s Global Assessment Score, a Subjects’ Global Assessment Score, lesion counts, cutaneous tolerability, and adverse events. Results APS 5% lotion demonstrated statistically significant improvement when compared to v

ehicle in all of the parameters measured. The adverse event frequency and cutaneous tolerability profile for APS 5% lotion were similar to vehicle. Limitations Adjunctive topical or oral agents and their impact on acne were not studied in this trial. Conclusions This study demonstrates that 5% sodium L-ascorbyl-2-phosphate is efficacious as monotherapy for the treatment of acne. APS 5% lotion offers a novel addition to our current acne armamentarium.