Amber photobiomodulation versus tranexamic acid for the treatment of melasma: protocol for a double-blind, randomised controlled trial

BMJ Open · 4 authors, 2 centres

AI SUMMARY

FIDELITY 82%

POPULATIONWomen aged 35-50 years with facial melasma, skin phototypes II-IV, without clinical skin comorbidities

INTERVENTIONAmber photobiomodulation (590 nm, 20 J/cm²) once weekly for 12 weeks plus placebo cosmetic twice daily

COMPARISONSham photobiomodulation once weekly for 12 weeks plus 5% liposomal tranexamic acid cosmetic twice daily

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AGENT 01 · STRUCTURED SUMMARY

TRACE TO SOURCE

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TL;DR

This protocol describes a double-blind, randomised non-inferiority trial comparing amber photobiomodulation (590 nm) to liposomal tranexamic acid for melasma in women. The primary outcome is the Melasma Area and Severity Index (MASI) at 12 weeks, with a non-inferiority margin of 0.3 MASI units. If non-inferiority is demonstrated, amber PBM could offer a non-invasive alternative to topical tranexamic acid for melasma treatment.

Full summary

2,856 CHARS

**Background:** Melasma is a common hyperpigmentation disorder predominantly affecting women, with significant psychological impact and no definitive treatment. Photobiomodulation (PBM) using amber light (590 nm) has shown in vitro efficacy by inhibiting tyrosinase, inducing autophagy, and reducing melanin content, similar to tranexamic acid (TXA). However, no randomised controlled trials have evaluated amber PBM for melasma. This protocol aims to compare amber PBM to liposomal TXA in a non-inferiority design.

**Methods:** This is a controlled, randomised, double-blind, non-inferiority trial conducted at two centres in São Paulo, Brazil. Fifty-four women aged 35-50 years with facial melasma and skin phototypes II-IV will be randomised 1:1 to receive either active PBM (590 nm, 20 J/cm², once weekly for 12 weeks) plus a placebo cosmetic, or sham PBM plus 5% liposomal TXA cosmetic (applied twice daily). Exclusion criteria include use of oral contraceptives, hormone replacement, photosensitive drugs, autoimmune disease, and recent facial treatments. The primary outcome is the Melasma Area and Severity Index (MASI) at week 12, with a non-inferiority margin of 0.3 points. Secondary outcomes include corneomelametry (epidermal melanin content), photographic records, Global Skin Diagnosis (0-6 scale), and the Brazilian Portuguese version of the Melasma Quality of Life Questionnaire (MELASQoL, score 10-70). Assessments occur at baseline, week 6, week 12, and follow-up at weeks 16 and 20. Data will be analysed using intention-to-treat with generalised mixed models; α < 0.05 is considered significant. The sample size calculation assumed a standard deviation of 0.36 based on prior TXA data, with 80% power and a one-sided alpha of 0.025, yielding 23 per group; with 15% dropout, 27 per group (total 54) are needed.

**Key Results:** This is a protocol paper; no results are reported. The study is ongoing, with recruitment from March 2023 to September 2024 and completion expected by December 2024. The protocol was approved by the Research Ethics Committee of Universidade Nove de Julho (no. 5,332,384) and registered at ClinicalTrials.gov (NCT05326997).

**Clinical Implications:** If amber PBM is found non-inferior to TXA, it could provide a non-invasive, needle-free alternative for melasma treatment, potentially avoiding side effects of topical TXA (e.g., irritation) and offering a novel mechanism via autophagy induction. The study's strengths include blinding, active control, and objective (corneomelametry) plus subjective (MASI, quality of life) outcomes. Limitations include the need for precise light parameter reproduction across devices and potential hyperpigmentation at higher radiant exposures (though 20 J/cm² is below reported thresholds). This trial may establish a new clinical protocol for melasma using amber PBM.

PICO

PPOPULATION

Women aged 35-50 years with facial melasma, skin phototypes II-IV, without clinical skin comorbidities

IINTERVENTION

Amber photobiomodulation (590 nm, 20 J/cm²) once weekly for 12 weeks plus placebo cosmetic twice daily

OOUTCOME

Primary: Melasma Area and Severity Index (MASI) at week 12. Secondary: corneomelametry, photographic records, Global Skin Diagnosis, Melasma Quality of Life Questionnaire (MELASQoL), adverse effects

STUDY TYPE

RCT

SPECIALTY

dermatology

SUMMARISED BY

AI pipeline

FIDELITY CHECK

82% · B

ORIGINAL PAPER

PMC10364183

Amber photobiomodulation versus tranexamic acid for the treatment of melasma: protocol for a double-blind, randomised controlled trial

BMJ Open

READ THE FULL PAPER

ABSTRACT

Abstract Introduction Photobiomodulation (PBM) has been suggested as an alternative treatment for melasma. In vitro studies have shown PBM with amber light inhibits the tyrosinase enzyme, induces autophagy and reduces the melanin content, but randomised controlled clinical trials are still needed. This study aims to evaluate the efficacy of amber PBM (590 nm) in the treatment of melasma compared with liposomal tranexamic acid. Methods and analysis This study is a controlled, randomised, double-blind, non-inferiority trial. This study will be performed in two centres (Universidade Nove de Julho Facility, Campus Vergueiro, and Galache Odontology Clinic, São Caetano do Sul, both in São Paulo State, Brazil). The sample (54 participants) will be divided into two groups in a 1:1 ratio; one group will receive active PBM and a placebo cosmetic and the other will receive sham PBM and liposomal tranexamic acid. Women presenting facial melasma, aged 35–50 years, with skin phototypes II–IV, will be eligible for inclusion. Women who use oral contraceptives, intrauterine devices, hormone replacement or photosensitive drugs, those with autoimmune disease and those who have undergone facial treatments in the last 3 months will be excluded from the study. The participants will receive PBM weekly for 12 weeks and will use the cosmetic two times per day at home during this period. The severity of melasma will be evaluated through the Melasma Area and Severity Index (MASI) as the primary outcome; pigmentation of the epidermis evaluated by corneomelametry, the photographic records, the global diagnosis of the face and the quality-of-life questionnaire (Brazilian Portuguese version of the Melasma Quality of Life Questionnaire) will assessed as secondary outcomes. All assessments will be made before starting the study (week 0), mid-study at 6 weeks and at the completion of treatment (week 12). MASI will also be evaluated during follow-up (weeks 16 and 20). The data will be analysed based on the intention-to-treat analysis using a generalised mixed model, and α <0.05 will be considered statistically significant. Ethics and dissemination The protocol was approved by the Research Ethics Committee of Universidade Nove de Julho (5 332 384). All participants will fill out the patient informed consent form. The results obtained in this trial will be presented at conferences and submitted for publication. Trial registration number ClinicalTrials.gov Registry ( NCT05326997 ). Keywords: Laser therapy, Photodermatology, Adult dermatology

CITATION EXPORT

Thais Rodrigues Galache, Marcelo Galache, Michelle Mota Sena et al.. Amber photobiomodulation versus tranexamic acid for the treatment of melasma: protocol for a double-blind, randomised controlled trial. BMJ Open. (2023). https://doi.org/10.1136/bmjopen-2023-073568

AUTHORS

4 · 2 CENTRES

Thais Rodrigues Galache, Marcelo Galache, Michelle Mota Sena, Christiane Pavani

1Postgraduate Program in Biophotonics Applied to the Health Sciences, Universidade Nove de Julho (UNINOVE), São Paulo, SP, Brazil
2Clínica, Odontologia Galache, São Caetano do Sul, Brazil