Introduction: The aim of this study was to assess the efficacy and safety of 15% azelaic acid (AzA) gel in treating acne-induced post-inflammatory erythema (PIE) and post-inflammatory hyperpigmentation (PIH). The effects of 15% AzA gel on acne, skin barrier function, and quality of life were also evaluated.
Methods: A total of 72 patients with mild to moderate acne were enrolled in a randomized, double-blind, placebo-controlled trial. Patients were divided into two groups: patients in the AzA group applied 15% AzA gel twice daily for 12 weeks, and those in the placebo group applied AzA-free gel. Clinical evaluations using non-invasive skin detection technologies, including VISIA skin analysis, dermoscopy, and skin physiological function tests, were performed at 0, 4, 8, and 12 weeks. Main outcome measures included the post-acne hyperpigmentation index (PAHPI), melanin, hemoglobin, individual typology angle, water content, transepidermal water loss, and sebum. Investigator Global Assessment) and Dermatology Life Quality Index (DLQI) assessments were conducted at weeks 0 and 12. Adverse reactions were recorded.
Results: Of the 72 patients at study initiation, 60 completed the trial. At 8 and 12 weeks, patients in the AzA group showed significantly reduced PAHPI for PIE lesions compared to baseline and patients receiving placebo (P < 0.05). Patients in both groups exhibited reduced PIH lesions at weeks 8 and 12 that differed significantly from baseline (P < 0.05). Hemoglobin content decreased significantly in AzA-treated PIE lesions compared to those treated with placebo at week 12 (P < 0.05). Melanin content decreased significantly in AzA-treated PIH lesions at week 12 (P < 0.05). The AzA group showed higher improvement in DLQI (P < 0.05), and greater overall satisfaction (P < 0.05) compared to placebo.
Conclusion: The results indicate that 15% AzA gel effectively improved acne-induced PIE and PIH with minimal adverse reactions, making it a viable clinical application. In the study population, it had no adverse effects on skin barrier function and contributed positively to acne improvement and patient quality of life.
Trial registration: This study was registered with the Chinese Clinical Trial Registry (ChiCTR.org.cn) under the identifier ChiCTR2300076959. The registration date was 25 October 2023, retrospectively registered.
Keywords: Acne; Azelaic acid; Post-inflammatory erythema; Post-inflammatory hyperpigmentation; Quality of life; Skin barrier.
© 2024. The Author(s).