Comparative Study Of Photodynamic Therapy With Riboflavin-Tryptophan Gel And 13% 5-Aminolevulinic Acid In The Treatment Of Mild To Moderate Acne Vulgaris

BACKGROUND: Non-invasive photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) has been used as an alternative acne treatment for many years. Riboflavin and tryptophan are newly introduced photosensitizers. OBJECTIVE: To compare the efficacy of PDT with riboflavin-tryptophan (RT) gel with that of 13% ALA for the treatment of facial acne. METHODS: We performed a double-blind, split-face study of 37 subjects with mild to moderate facial acne vulgaris. RT gel was applied to half of the face, and 13% ALA was applied to the other half. Then, the whole face was irradiated using a blue light-emitting diode for 20 mins. Four treatment sessions were performed over a 4-week duration, at 1-week interval. The acne lesion counts and acne severity were assessed. Sebum secretion, Propionibacterium acne colonization, pore size, and skin texture were also evaluated. RESULTS: PDT with RT gel demonstrated good efficacy, non-inferior to ALA for acne treatment, with a significant reduction in acne lesion counts, severity grading, porphyrin, and sebum output. The pore size and skin texture were improved. Side-effects were minimal and well tolerated in all subjects. CONCLUSION: PDT therapy with RT gel is an effective alternative treatment for acne vulgaris.