Efficacy and Safety of Letibotulinum Toxin A for the Treatment of Melasma in Two Different Dilutions: A Randomized Double-Blind Split-Face Study
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Issued Date
2025-07-01
Resource Type
eISSN
20726651
Scopus ID
2-s2.0-105011873246
Journal Title
Toxins
Volume
17
Issue
7
Rights Holder(s)
SCOPUS
Bibliographic Citation
Toxins Vol.17 No.7 (2025)
Suggested Citation
Pongklaokam J., Manuskiatti W., Wanitphakdeedecha R., Maneeprasopchoke P., Thongjaroensirikul P., Nokdhes Y., Abad-Constantino R.M.R., Bhorntarakcharoen W., Sittiwanaruk S., Techapichetvanich T. Efficacy and Safety of Letibotulinum Toxin A for the Treatment of Melasma in Two Different Dilutions: A Randomized Double-Blind Split-Face Study. Toxins Vol.17 No.7 (2025). doi:10.3390/toxins17070349 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/111486
Title
Efficacy and Safety of Letibotulinum Toxin A for the Treatment of Melasma in Two Different Dilutions: A Randomized Double-Blind Split-Face Study
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Abstract
Background: Melasma is an acquired hyperpigmentation disorder with multifactorial etiologies and limited response to conventional therapies. Recent evidence suggests that Botulinum Toxin A (BoNT-A) may modulate ultraviolet (UV)-induced pigmentation and offer therapeutic benefits. Objective: We sought to evaluate the efficacy and safety of two intradermal dilutions of Letibotulinum toxin A (LetiBoNT-A) in Thai patients with melasma. Methods: In this randomized, double-blind, split-face study, 30 participants aged 32–62 years received a single intradermal injection of LetiBoNT-A, with 20 units administered per cheek. A 1:5 dilution was injected on one side of the face, and a 1:10 dilution was injected on the contralateral side. Outcomes were evaluated over a 6-month period using the Hemi-modified Melasma Area and Severity Index (Hemi-mMASI), VISIA<sup>®</sup> brown spot analysis, and quantitative assessments of skin texture. Results: Both dilutions significantly improved Hemi-mMASI scores (1:5, p = 0.043; 1:10, p = 0.002) and brown spots (1:5, p = 0.002; 1:10, p < 0.001). The 1:10 dilution showed earlier and more sustained improvements. Subgroup analysis revealed greater reductions in Hemi-mMASI scores among patients with telangiectatic melasma, particularly with the 1:10 dilution, though they were not statistically significant. Additionally, the 1:10 dilution significantly reduced pore volume, pore area, and sebum levels. One case of transient facial asymmetry was reported with the 1:5 dilution. Conclusions: LetiBoNT-A is a safe and effective adjunct in melasma treatment. The 1:10 dilution offered superior clinical outcomes.