Efficacy of Repeated Low-level Red-light Therapy in Myopia Control

Efficacy of Repeated Low-level Red-light Therapy in Myopia Control: a Single Arm Controlled Trial

Low-level red-light technology provides a new and innovative myopia control approach. This strategy enables relatively high energies of light to be delivered at much shorter durations of exposure to induce the myopia control effect. The efficacy of the low-level red-light technology has been proven in a Chinese population. This trial demonstrated that 3-minutes per session twice a day repeated low-level red-light treatment controlled 87.7% of refraction progression and 76.8% of axial length elongation when the time of compliance to the treatment was 75%. Repeating this RCT in culturally diverse groups will confirm and translate this technology into a solution for myopia control globally.

Study Overview

• Status: Recruiting
• Conditions: Myopia
• Intervention / Treatment: Device: Low-level Red Light Therapy Device

Detailed Description

The purpose of this study is to assess the safety and efficacy of low level red light therapy in myopia control in African, Hispanic, and Caucasian children. This is a prospective, multi-ethnic, parallel-controlled randomized trial that will enroll myopic children aged 8-13 years old as subjects. On top of wearing single vision spectacles, subjects in the intervention group will receive treatment twice a day from Monday to Friday, with each treatment lasting for 3 minutes at a minimal interval of 4 hours. Subjects in the control group will wear single vision spectacles. The study will evaluate axial elongation, cycloplegic spherical equivalent change, changes in other biological parameters (except axial length), and uncorrected and best corrected visual acuity of the two groups of subjects at 1 month, 3 months, 6 months, and 12 months after enrollment. The study plans to conduct an interim analysis at a three-month follow-up. The enrollment target is 90 participants: 30 Hispanic Children (15 control and 15 treatment) , 30 African Children (15 control and 15 treatment), and 30 Caucasian Children (15 control and 15 treatment).

• Study Type: Interventional
• Enrollment (Estimated): 90
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Tiffany Chen, MD; Phone Number: 4155143503; Email: Tiffany.A.Chen@ucsf.edu

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94143
      • Recruiting
      • University of California, San Francisco
      • Sub-Investigator: Ying Han, MD/PhD
      • Contact: Jenny Lu; Phone Number: 415-476-5321; Email: jenny.lu@ucsf.edu
      • Principal Investigator: Tiffany Chen, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 8 years to 13 years (Child)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Provision of consent
2. Non-Chinese Ethnicity
3. Age: ≥8 and ≤13 years at enrollment
4. Myopia: Spherical equivalent refractions (SERs) under cycloplegia: -1.00 to -5.00 diopters (D)

4) Astigmatism of 2.50 D or less 5) Anisometropia of 1.50 D or less 6) Corrected monocular logMAR visual acuity (VA): 1.0 or better 7) Consent to participate in random allocation of grouping 8) Fluent in English 9) Willing and able to participate in all required activities of the study6) Corrected monocular logMAR visual acuity (VA): 1.0 or better

Exclusion Criteria:

1. Strabismus and binocular vision abnormalities in either eye
2. Ocular abnormalities in either eye or other systemic abnormalities that affect participate in all required activities of the study.
3. Other reasons, including but not limited to severe physical and cognitive disability, that the physician may consider inappropriate for enrollment
4. Noncompliance with treatment
5. Children whose parents do not sign informed consent

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low Level Red Light Treatment Arm; On top of wearing single vision spectacles, subjects in the intervention group will receive low-level red light treatment twice a day from Monday to Friday, with each treatment lasting for 3 minutes at a minimal interval of 4 hours.	Device: Low-level Red Light Therapy Device; The treatment device used in this study is a semi-conductor laser product (Eyerising International Pty Ltd, Melbourne, Australia), emitting low-level red-light with a wavelength of 650 ± 10 nm. Based on calculations done by the manufacturer, the device provides light at a power of 2.00 ± 0.50 mW.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Axial Length (AL) (mm) at Baseline	Axial Length (AL) is characterized as the combination of anterior chamber depth, lens thickness and vitreous chamber depth and measured by results from the IOLMaster. AL will be taken at the 1-, 3-, 6-, and 12-month follow-up visits.	1 month
Axial Length (AL) (mm) at Month 1	Axial Length (AL) is characterized as the combination of anterior chamber depth, lens thickness and vitreous chamber depth and measured by results from the IOLMaster. AL will be taken at the 1-, 3-, 6-, and 12-month follow-up visits.	1 month
Axial Length (AL) (mm) at Month 3	Axial Length (AL) is characterized as the combination of anterior chamber depth, lens thickness and vitreous chamber depth and measured by results from the IOLMaster. AL will be taken at the 1-, 3-, 6-, and 12-month follow-up visits.	3 months
Axial Length (AL) (mm) at Month 6	Axial Length (AL) is characterized as the combination of anterior chamber depth, lens thickness and vitreous chamber depth and measured by results from the IOLMaster. AL will be taken at the 1-, 3-, 6-, and 12-month follow-up visits.	6 months
Axial Length (AL) (mm) at Year 1	Axial Length (AL) is characterized as the combination of anterior chamber depth, lens thickness and vitreous chamber depth and measured by results from the IOLMaster. AL will be taken at the 1-, 3-, 6-, and 12-month follow-up visits.	1 Year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Spherical Equivalent Refraction (SER) (Diopter) at Baseline	Spherical equivalent (Diopter, D) is the spherical power plus half of the cylindrical power. Cycloplegia is induced with one drop of Alcaine 0.5% followed by two drops of 1% cyclopentolate administered at 0, 5th to each eye. The third drop of cyclopentolate is used if the light reflex exists after 20 minute. The light reflex and pupil dilation is checked after an additional 15 minutes. Dilation and light reflex status is recorded and full cycloplegia is justified if the pupil dilates to 6 millimeters or greater and the light reflex is absent. Refraction is performed with an auto-refractor. The data on spherical and cylindrical power and axis is automatically extracted from the auto-refractor. This will be taken at 1-,3-, 6-, and 12-month follow-up visits.	Baseline
Spherical Equivalent Refraction (SER) (Diopter) at Month 1	Spherical equivalent (Diopter, D) is the spherical power plus half of the cylindrical power. Cycloplegia is induced with one drop of Alcaine 0.5% followed by two drops of 1% cyclopentolate administered at 0, 5th to each eye. The third drop of cyclopentolate is used if the light reflex exists after 20 minute. The light reflex and pupil dilation is checked after an additional 15 minutes. Dilation and light reflex status is recorded and full cycloplegia is justified if the pupil dilates to 6 millimeters or greater and the light reflex is absent. Refraction is performed with an auto-refractor. The data on spherical and cylindrical power and axis is automatically extracted from the auto-refractor. This will be taken at 1-,3-, 6-, and 12-month follow-up visits.	1 month
Spherical Equivalent Refraction (SER) (Diopter) at Month 3	Spherical equivalent (Diopter, D) is the spherical power plus half of the cylindrical power. Cycloplegia is induced with one drop of Alcaine 0.5% followed by two drops of 1% cyclopentolate administered at 0, 5th to each eye. The third drop of cyclopentolate is used if the light reflex exists after 20 minute. The light reflex and pupil dilation is checked after an additional 15 minutes. Dilation and light reflex status is recorded and full cycloplegia is justified if the pupil dilates to 6 millimeters or greater and the light reflex is absent. Refraction is performed with an auto-refractor. The data on spherical and cylindrical power and axis is automatically extracted from the auto-refractor. This will be taken at 1-,3-, 6-, and 12-month follow-up visits.	3 months
Spherical Equivalent Refraction (SER) (Diopter) at Month 6	Spherical equivalent (Diopter, D) is the spherical power plus half of the cylindrical power. Cycloplegia is induced with one drop of Alcaine 0.5% followed by two drops of 1% cyclopentolate administered at 0, 5th to each eye. The third drop of cyclopentolate is used if the light reflex exists after 20 minute. The light reflex and pupil dilation is checked after an additional 15 minutes. Dilation and light reflex status is recorded and full cycloplegia is justified if the pupil dilates to 6 millimeters or greater and the light reflex is absent. Refraction is performed with an auto-refractor. The data on spherical and cylindrical power and axis is automatically extracted from the auto-refractor. This will be taken at 1-,3-, 6-, and 12-month follow-up visits.	6 months
Spherical Equivalent Refraction (SER) (Diopter) at Year 1	Spherical equivalent (Diopter, D) is the spherical power plus half of the cylindrical power. Cycloplegia is induced with one drop of Alcaine 0.5% followed by two drops of 1% cyclopentolate administered at 0, 5th to each eye. The third drop of cyclopentolate is used if the light reflex exists after 20 minute. The light reflex and pupil dilation is checked after an additional 15 minutes. Dilation and light reflex status is recorded and full cycloplegia is justified if the pupil dilates to 6 millimeters or greater and the light reflex is absent. Refraction is performed with an auto-refractor. The data on spherical and cylindrical power and axis is automatically extracted from the auto-refractor. This will be taken at 1-,3-, 6-, and 12-month follow-up visits.	1 year
Corneal radius of curvature (CC) at Baseline	Corneal radius of curvature (CC) is taken and characterized with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. CC will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	Baseline
Corneal radius of curvature (CC) at Month 1	Corneal radius of curvature (CC) is taken and characterized with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. CC will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 month
Corneal radius of curvature (CC) at Month 3	Corneal radius of curvature (CC) is taken and characterized with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. CC will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	3 months
Corneal radius of curvature (CC) at Month 6	Corneal radius of curvature (CC) is taken and characterized with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. CC will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	6 months
Corneal radius of curvature (CC) at Year 1	Corneal radius of curvature (CC) is taken and characterized with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. CC will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 year
Anterior Chamber Depth (ACD) at Baseline	Anterior chamber depth (ACD) is characterized as measures of taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. ACD will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	Baseline
Anterior Chamber Depth (ACD) at Month 1	Anterior chamber depth (ACD) is characterized as measures of taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. ACD will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 month
Anterior Chamber Depth (ACD) at Month 3	Anterior chamber depth (ACD) is characterized as measures of taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. ACD will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	3 months
Anterior Chamber Depth (ACD) at Month 6	Anterior chamber depth (ACD) is characterized as measures of taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. ACD will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	6 months
Anterior Chamber Depth (ACD) at Year 1	Anterior chamber depth (ACD) is characterized as measures of taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. ACD will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 year
White-to-White (WTW) at Baseline	White to white (mm) is characterized as measures taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	Baseline
White-to-White (WTW) at Month 1	White to white (mm) is characterized as measures taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 month
White-to-White (WTW) at Month 3	White to white (mm) is characterized as measures taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	3 months
White-to-White (WTW) at Month 6	White to white (mm) is characterized as measures taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	6 months
White-to-White (WTW) at Year 1	White to white (mm) is characterized as measures taken with an IOLMaster which is an ocular biometric measurement instrument that uses the principle of partial coherence interferometry (PCI) to perform non-contact ocular biometric measurements. as the difference between each follow-up visit and baseline values. White-to-white (WTW) measurements will be taken at the 1-,3-, 6-, and 12-month follow-up visits.	1 year
Undercorrected Visual Acuity at Baseline	Undercorrected Visual Acuity is characterized by line-by-line examinations and methods for determining visual acuity will be conducted using the lowest line with the number of correctly identified optotypes ≥4/5 at 4 meters, or the lowest line with the number of optotypes ≥4/5 at 1 meter after conversion. This will be taken at the 1-,3-, 6-, and 12-month follow-up. An Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR E chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will measure distance visual acuity at a distance of 4 meters (a reflecting mirror will be used to achieve this testing distance if the space is limited). This visual acuity chart will be placed at a height such that the line of 20/20 is the same as the height of the participant's eyes.	Baseline
Undercorrected Visual Acuity at Month 1	Undercorrected Visual Acuity is characterized by line-by-line examinations and methods for determining visual acuity will be conducted using the lowest line with the number of correctly identified optotypes ≥4/5 at 4 meters, or the lowest line with the number of optotypes ≥4/5 at 1 meter after conversion. This will be taken at the 1-,3-, 6-, and 12-month follow-up. An Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR E chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will measure distance visual acuity at a distance of 4 meters (a reflecting mirror will be used to achieve this testing distance if the space is limited). This visual acuity chart will be placed at a height such that the line of 20/20 is the same as the height of the participant's eyes.	1 month
Undercorrected Visual Acuity at Month 3	Undercorrected Visual Acuity is characterized by line-by-line examinations and methods for determining visual acuity will be conducted using the lowest line with the number of correctly identified optotypes ≥4/5 at 4 meters, or the lowest line with the number of optotypes ≥4/5 at 1 meter after conversion. This will be taken at the 1-,3-, 6-, and 12-month follow-up. An Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR E chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will measure distance visual acuity at a distance of 4 meters (a reflecting mirror will be used to achieve this testing distance if the space is limited). This visual acuity chart will be placed at a height such that the line of 20/20 is the same as the height of the participant's eyes.	3 months
Undercorrected Visual Acuity Month 6	Undercorrected Visual Acuity is characterized by line-by-line examinations and methods for determining visual acuity will be conducted using the lowest line with the number of correctly identified optotypes ≥4/5 at 4 meters, or the lowest line with the number of optotypes ≥4/5 at 1 meter after conversion. This will be taken at the 1-,3-, 6-, and 12-month follow-up. An Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR E chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will measure distance visual acuity at a distance of 4 meters (a reflecting mirror will be used to achieve this testing distance if the space is limited). This visual acuity chart will be placed at a height such that the line of 20/20 is the same as the height of the participant's eyes.	6 months
Undercorrected Visual Acuity at Year 1	Undercorrected Visual Acuity is characterized by line-by-line examinations and methods for determining visual acuity will be conducted using the lowest line with the number of correctly identified optotypes ≥4/5 at 4 meters, or the lowest line with the number of optotypes ≥4/5 at 1 meter after conversion. This will be taken at the 1-,3-, 6-, and 12-month follow-up. An Early Treatment Diabetic Retinopathy Study (ETDRS) logMAR E chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will measure distance visual acuity at a distance of 4 meters (a reflecting mirror will be used to achieve this testing distance if the space is limited). This visual acuity chart will be placed at a height such that the line of 20/20 is the same as the height of the participant's eyes.	1 year
Best Corrected Visual Acuity (BCVA) under non-cycloplegia and strabismus examination at Baseline	BCVA will be measured as results from autorefraction under non-cycloplegia will be performed for collection of all measurements. The best-corrected visual acuity of the child's left and right eyes will be recorded separately.	Baseline
Best Corrected Visual Acuity (BCVA) under non-cycloplegia and strabismus examination at Month 1	BCVA will be measured as results from autorefraction under non-cycloplegia will be performed for collection of all measurements. The best-corrected visual acuity of the child's left and right eyes will be recorded separately.	1 month
Best Corrected Visual Acuity (BCVA) under non-cycloplegia and strabismus examination at Month 3	BCVA will be measured as results from autorefraction under non-cycloplegia will be performed for collection of all measurements. The best-corrected visual acuity of the child's left and right eyes will be recorded separately.	3 months
Best Corrected Visual Acuity (BCVA) under non-cycloplegia and strabismus examination at Month 6	BCVA will be measured as results from autorefraction under non-cycloplegia will be performed for collection of all measurements. The best-corrected visual acuity of the child's left and right eyes will be recorded separately.	6 months
Best Corrected Visual Acuity (BCVA) under non-cycloplegia and strabismus examination at Year 1	BCVA will be measured as results from autorefraction under non-cycloplegia will be performed for collection of all measurements. The best-corrected visual acuity of the child's left and right eyes will be recorded separately.	1 year
Choroidal Thickness (ChT) at Baseline	ChT is measured as the perpendicular distance from the outer portion of the hyperreflective line corresponding to the retinal pigment epithelium to the posterior edge of the choroid as demarcated by the hyperreflective line corresponding to the chorioscleral interface using built-in automated layer segmentation software. This will be taken using the TOPCON Swept Source DRI OCT which is a non-contact, high-resolution tomographic and biomicroscopic imaging device for in-vivo viewing and measurement of posterior ocular structures.	Baseline
Choroidal Thickness (ChT) at Month 1	ChT is measured as the perpendicular distance from the outer portion of the hyperreflective line corresponding to the retinal pigment epithelium to the posterior edge of the choroid as demarcated by the hyperreflective line corresponding to the chorioscleral interface using built-in automated layer segmentation software. This will be taken using the TOPCON Swept Source DRI OCT which is a non-contact, high-resolution tomographic and biomicroscopic imaging device for in-vivo viewing and measurement of posterior ocular structures.	1 month
Choroidal Thickness (ChT) at Months 3	ChT is measured as the perpendicular distance from the outer portion of the hyperreflective line corresponding to the retinal pigment epithelium to the posterior edge of the choroid as demarcated by the hyperreflective line corresponding to the chorioscleral interface using built-in automated layer segmentation software. This will be taken using the TOPCON Swept Source DRI OCT which is a non-contact, high-resolution tomographic and biomicroscopic imaging device for in-vivo viewing and measurement of posterior ocular structures.	3 months
Choroidal Thickness (ChT) at Month 6	ChT is measured as the perpendicular distance from the outer portion of the hyperreflective line corresponding to the retinal pigment epithelium to the posterior edge of the choroid as demarcated by the hyperreflective line corresponding to the chorioscleral interface using built-in automated layer segmentation software. This will be taken using the TOPCON Swept Source DRI OCT which is a non-contact, high-resolution tomographic and biomicroscopic imaging device for in-vivo viewing and measurement of posterior ocular structures.	6 months
Choroidal Thickness (ChT) at 1 Year	ChT will be measured as the difference between each follow-up visit and baseline values.ChT is measured as the perpendicular distance from the outer portion of the hyperreflective line corresponding to the retinal pigment epithelium to the posterior edge of the choroid as demarcated by the hyperreflective line corresponding to the chorioscleral interface using built-in automated layer segmentation software. This will be taken using the TOPCON Swept Source DRI OCT which is a non-contact, high-resolution tomographic and biomicroscopic imaging device for in-vivo viewing and measurement of posterior ocular structures. ChT will be taken at 1-,3-, 6-, and 12-month follow-up visits.	1 year

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Collaborators: University of Melbourne
• Investigators: Principal Investigator: Tiffany Chen, MD, University of California, San Francisco

Publications and helpful links

General Publications

• Holden BA, Fricke TR, Wilson DA, Jong M, Naidoo KS, Sankaridurg P, Wong TY, Naduvilath TJ, Resnikoff S. Global Prevalence of Myopia and High Myopia and Temporal Trends from 2000 through 2050. Ophthalmology. 2016 May;123(5):1036-42. doi: 10.1016/j.ophtha.2016.01.006. Epub 2016 Feb 11.

Study record dates

Study Major Dates

• Study Start (Actual): July 14, 2023
• Primary Completion (Estimated): January 14, 2027
• Study Completion (Estimated): January 14, 2027

Study Registration Dates

• First Submitted: September 21, 2022
• First Submitted That Met QC Criteria: November 2, 2022
• First Posted (Actual): November 4, 2022

Study Record Updates

• Last Update Posted (Actual): January 28, 2026
• Last Update Submitted That Met QC Criteria: January 26, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: myopia
• Additional Relevant MeSH Terms: Eye Diseases; Refractive Errors; Myopia
• Other Study ID Numbers: 21-35793

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results after deidentification(text, tables, figures, and appendices).
• IPD Sharing Time Frame: Immediately following publication. No end date.
• IPD Sharing Access Criteria: Investigators whose proposed use of the data has been approved by an independent review committee identified for this purpose. For individual participant data meta-analysis.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No