Abstract
BACKGROUND: Detachable microneedles (DMNs) are dissolvable microneedles that detach from the base during administration. The use of DMNs-containing steroids for acne has never been investigated. METHODS: Thirty-five patients with facial inflammatory acne were evaluated for acne treatment efficacy and safety of DMNs and DMNs containing triamcinolone acetonide (TA) via a 28-day randomized, double-blind, controlled trial. Four inflammatory acne lesions were selected from each participant and randomly treated with a single application of 700 µm DMNs containing 262.02 ± 15.62 µg TA (700DMNTA), 1000 µm DMNs containing 160.00 ± 34.92 µg TA (1000DMNTA), 700 µm DMN without TA (700DMN), and a control. Efficacy was measured by assessing physical grading, diameter, volume, erythema index, and melanin index. Safety was evaluated by assessing reports of adverse effects from patients and physicians. RESULTS: All three treatment groups achieved resolution of inflammatory acne significantly faster than the control group, with median times for resolution of 4.6, 5.25, 6.7, and 8.1 days in the 1000DMNTA, 700DMNTA, 700DMN, and control, respectively. When compared to the control group, the diameters and post-acne erythema of inflammatory acne were significantly reduced in the treatment groups. The 1000DMNTA decreased acne size and erythema more than other treatments. DMNTA also tended to decrease acne size and erythema more than DMN with no TA, but there was no statistically significant difference. All participants preferred DMN over conventional intralesional steroid injection due to less pain and self-application. No adverse effect was observed. CONCLUSION: DMNTA is a safe, effective alternative treatment for inflammatory acne and significantly reduces post-acne erythema.