Clinical efficacy of 5-aminolevulinic acid photodynamic therapy in the treatment of moderate to severe facial acne vulgaris

Abstract

Acne vulgaris is considered as a therapeutic challenge in terms of managing ongoing symptoms and preventing scar formation. Although there are many available treatments for alleviating acne, therapies for resistant or moderate-to-severe forms have been limited to systemic agents that are accompanied by potentially severe side-effects. While, aminolevulinic acid (ALA) photodynamic therapy (PDT) has increasingly been used as a simple and safe therapeutic option of acne vulgaris, the clinical efficacy requires confirmation in further studies. The aim of this study was to investigate the efficacy and safety of 5-ALA-PDT in the treatment of moderate-to-severe facial acne vulgaris. A total of 50 patients with moderate-to-severe facial acne were enrolled in the study and randomly divided equally into a therapy group and a control group. In the therapy group, the patients were treated with 5% 5-ALA for 1.5 h, followed by three 20-min doses of infrared radiation once a week; in the control group, the patients were treated with three 20 min doses of infrared radiation without 5-ALA once a week. Both treatments lasted for 3 weeks. The clinical efficacy was determined by evaluating acne lesion counts at weeks 0, 2, 4 and 6. Total efficacy rate (TER) was the primary endpoint of the study, and was defined as the proportion of the patients whose treatment effectiveness evaluation was cured (≥90% of skin lesions improved) and excellent (60-89% improvement). Adverse effects were recorded throughout the study. The study was completed by 24 patients in the therapy group and 23 patients in the control group. The numbers of acne lesions significantly decreased. The TER of the therapy group was significantly higher than that of the control group at weeks 4 and 6. Adverse effects were observed in 12 patients of the therapy group and 2 patients of the control group. In the therapy group the most common adverse effect was a burning sensation (n=7), followed by transient hyperpigmentation (n=3) and acute acneform lesions (n=2), while in control group, the 2 patients experienced flushing and dryness. The adverse effects were all cured by a symptomatic approach prior to the end of the study. 5-ALA-PDT combined with infrared radiation is an effective and safe therapy for moderate-to-severe facial acne.

Keywords: 5-aminolevulinic acid; facial acne; infrared radiation; photodynamic therapy.

Figure 1.

Effect in a female patient. (A) The left side of the face presented red papula and had four pimples prior to treatment with ALA-PDT. (B) The red papula darkened and pimples faded after three treatments. ALA, aminolevulinic acid; PDT, photodynamic therapy.

Figure 2.

Effect in a male patient. (A) The right side of the face had dull red papula and 12 red/pink nodules prior to treatment with ALA-PDT. (B) The dull red papula and nodules had faded away, and only brown-colored traces remained after three treatments. ALA, aminolevulinic acid; PDT, photodynamic therapy.