Repeated Low-Level Red-Light Therapy in Dry Age-Related Macular Degeneration

Safety and Efficacy of Repeated Low-Level Red-Light Therapy in Dry Age-Related Macular Degeneration: A Randomized Controlled Trial

This prospective, double-blind, randomized controlled trial aims to evaluate the efficacy and safety of repeated low-level red-light (RLRL) therapy in patients with dry age-related macular degeneration (AMD). The primary objective is to assess the effect of RLRL therapy on visual function in patients with dry AMD, while the secondary objective is to evaluate its safety and tolerability.

Seventy-four participants aged 50 years or older with dry AMD will be enrolled and randomly assigned in a 1:1 ratio to either the active RLRL intervention group (using the full device power) or the control group (sham device at 10% power). Group assignments will be masked to both participants and investigators. Participants will administer the treatment at home twice daily (3-minute sessions, with at least a 4-hour interval between sessions) over five consecutive weekdays each month for three months. A video tutorial will guide device usage, with ongoing support from the research team.

Before enrollment, participants will undergo a comprehensive assessment, including ocular and family history review, OCT, and fundus photography to confirm eligibility. Evaluations will occur at baseline, 1 month, and 3 months, covering best-corrected visual acuity (BCVA), slit-lamp examination, OCT, OCT angiography (OCTA), fundus autofluorescence (FAF), contrast sensitivity, color vision, electroretinography (ERG), visual-related quality of life (VRQL) questionnaires, and adverse event monitoring.

The primary outcome is the mean change in BCVA from baseline to 3 months. Secondary outcomes include changes in central drusen thickness, geographic atrophy (GA) size and progression, choroidal blood flow, contrast sensitivity, ERG responses, and VRQL scores.

Given the limited treatment options for dry AMD, which are primarily focused on lifestyle changes and nutritional supplements, this study investigates the potential of RLRL therapy as a novel, non-invasive treatment. The results may address the unmet medical need in dry AMD, potentially slowing disease progression and improving patients' quality of life.

Study Overview

• Status: Not yet recruiting
• Conditions: AMD - Age-Related Macular Degeneration
• Intervention / Treatment: Device: RLRL device; Device: Sham device

• Study Type: Interventional
• Enrollment (Estimated): 94
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Mingguang He; Phone Number: 85234002795; Email: mingguang.he@polyu.edu.hk
• Study Contact Backup: Name: Yanxian Chen; Phone Number: 85227666111; Email: yan-xian.chen@polyu.edu.hk

Study Locations

• China
  • Hong Kong
    • Hong Kong, Hong Kong, China
      • The Hong Kong Polytchnic University
      • Contact: Staff; Phone Number: 85227665111; Email: polyu@polyu.edu.hk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Age ≥ 50 years old.

2. Diagnosis of dry AMD in Age-Related Eye Disease Study (AREDS) category 2 to 4, as determined by color fundus photography and fundus autofluorescence imaging. The AREDS categories will be defined as follows:

   i) AREDS category 2 (early AMD): Multiple small drusen, a few intermediate drusen (63-124 μm in diameter), or retinal pigment epithelium (RPE) abnormalities ii) AREDS category 3 (intermediate AMD): Extensive intermediate drusen, including at least one large drusen (> 125 μm in diameter), or geographic atrophy (GA) not involving the center of the fovea.

   iii) AREDS category 4 (advanced/late AMD): GA involving the center of the macula.

   If both eyes meet the inclusion criteria, both eyes will be included in the study analysis.

3. ETDRS BCVA score between 50 and 75 (Snellen equivalent of 20/32 to 20/100). Willingness to provide written informed consent after being informed of the nature of the study.

Exclusion Criteria:

1. Previous or active neovascular maculopathy.
2. Presence of center involving GA within the central 500 μm of the ETDRS grid.
3. Ocular disease other than dry AMD that could cause drusen (glomerulonephritis Type 2, Autosomal dominant drusen), GA (North Carolina macular dystrophy), or mitochondrial disorders (parafoveal petaloid GA, Stargardt disease).
4. Invasive eye surgery (e.g. cataract extraction, capsulotomy) within 3 months.
5. Cognitive impairment or history of epilepsy.
6. Other significant ocular disease affecting visual acuity (e.g., diabetic macular edema, uncontrolled glaucoma, active uveitis, vitreoretinal disease, intraocular tumor, retinal vascular disease, lens opacities more severe than C2, N2, P2 [LOCS III]).

Afterimage > 5 min (contraindication of red-light therapy).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: RLRL therapy group; The RLRL therapy group will undergorepeated low-level red-light therapy (RLRL).The light power through a 4-mm pupil is 0.29 mW for the RLRL device.	Device: RLRL device; Each participant in the RLRL therapy group will be provided a repeated low-level red-light therapy (RLRL) device, which they are required to use twice daily for 3minutes per session, with a minimum interval of 4 hours between sessions (5 days a week) for three month.
Sham Comparator: Sham therapy group; The sham therapy group will use a sham device, which operates at only 10% of the active RLRL device's power. The light power through a 4-mm pupil is 0.03mW for the sham device.	Device: Sham device; Each participant in the sham group will be provided a sham therapy device, which they are required to use twice daily for 3minutes per session, with a minimum interval of 4 hours between sessions (5 days a week) for three month.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The mean change in BCVA measured by ETDRS chart	An Early Treatment Diabetic Retinopathy Study (ETDRS) chart (Precision Vision, Villa Park, Illinois, USA) with standard illumination will be used to measure distance visual acuity. Best corrected visual acuity and uncorrected visual acuity will be measured.	At 1month and 3 months compared to baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in central drusen volume measured by optical coherence tomography (OCT)	Spectral-domain OCT (Spectralis OCT; Heidelberg Engineering, Heidelberg, Germany) with 49 parallel B-scan lines will be used to image the study eye. The automated real-time (ART) function will average 16 frames per scan. Measurements will include sub-RPE macular drusen volume within the 6 × 6 mm ETDRS grid and mean central subfield sub-RPE drusen thickness within the central 1-mm ETDRS subfield. Automated and manually corrected segmentation of Bruch's membrane and the RPE, provided by the Heidelberg software, will be used for analysis.	At 1month and 3 months compared to baseline
Change in central drusen thickness measured by optical coherence tomography (OCT).	Spectral-domain OCT (Spectralis OCT; Heidelberg Engineering, Heidelberg, Germany) with 49 parallel B-scan lines will be used to image the study eye. The automated real-time (ART) function will average 16 frames per scan. Measurements will include sub-RPE macular drusen volume within the 6 × 6 mm ETDRS grid and mean central subfield sub-RPE drusen thickness within the central 1-mm ETDRS subfield. Automated and manually corrected segmentation of Bruch's membrane and the RPE, provided by the Heidelberg software, will be used for analysis.	At 1month and 3 months compared to baseline
Change in retinal sensitivity using microperimetry.	Retinal sensitivity will be assessed using microperimetry performed with the MP-3 microperimeter (NIDEK Co., Ltd., Gamagori, Japan). The device will be used to measure localized retinal sensitivity across the macular region following a standardized testing protocol. Retinal sensitivity thresholds and fixation stability parameters will be recorded and analyzed according to the manufacturer's recommendations.	At 1month and 3 months compared to baseline
Outcomes of visual-related quality of life (VRQL) assessed by the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25)	The 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) will be administered to assess VRQL. This instrument covers 12 subscales: general health, general vision, ocular pain, near vision, distance vision, social functioning, role limitations, mental health, dependency, driving, color vision, and peripheral vision. Each subscale score ranges from 0 to 100, with higher scores indicating better self-reported visual function.	At 3 months compared to baseline
Size of GA assessed by fundus autofluorescence (FAF) imaging	FAF will be acquired using 488-nm excitation (Spectralis OCT; Heidelberg Engineering, Heidelberg, Germany). GA lesions will be quantified with Region Finder software (Heidelberg Engineering), which provides semi-automated measurement of areas with homogeneous hypoautofluorescence and enables longitudinal assessment of lesion growth.	At 1month and 3 months compared to baseline
Change in contrast sensitivity using the Mars Letter Contrast Sensitivity Test	The Mars Letter Contrast Sensitivity Test (Mars Perceptrix, Chappaqua, NY, USA) will be performed under standardized photopic lighting at 50 cm. Participants will read letters sequentially from highest to lowest contrast, with contrast decreasing in 0.04 log unit steps. Testing will continue until two consecutive errors are made. Final scores will be calculated per manufacturer's guidelines and expressed in log contrast sensitivity units.	At 1month and 3 months compared to baseline

Collaborators and Investigators

• Sponsor: The Hong Kong Polytechnic University

Study record dates

Study Major Dates

• Study Start (Estimated): January 26, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: January 18, 2026
• First Submitted That Met QC Criteria: February 6, 2026
• First Posted (Actual): February 13, 2026

Study Record Updates

• Last Update Posted (Actual): February 13, 2026
• Last Update Submitted That Met QC Criteria: February 6, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Visual function; Red light therapy; Dry Age-Related Macular Degeneration
• Additional Relevant MeSH Terms: Eye Diseases; Retinal Diseases; Retinal Degeneration; Macular Degeneration
• Other Study ID Numbers: HSEARS20250917007

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: According to the relevant agreement, all parties involved must keep study data confidential throughout thestudy process.

Drug and device information, study documents

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