Final Analysis of LIGHTSITE I: A Double-Masked, Randomized, Sham-Controlled Study with Photobiomodulation in Dry Age-Related Macular Degeneration Subjects

Abstract

Purpose : The purpose of this study was to evaluate photobiomodulation (PBM) as a new treatment option in eyes with dry age-related macular degeneration (AMD). PBM uses wavelengths of light in the 500 nm to 1000 nm range to stimulate beneficial cellular activities. Recent evidence suggests that PBM improves visual and anatomical impairments observed in ocular disease states. Dry AMD is a prevalent ocular condition that results in significant visual dysfunction and blindness. The LIGHTSITE I study evaluated benefits of PBM therapy in dry AMD subjects.

Methods : Thirty subjects with dry AMD were enrolled into the study and randomized (1:1) into PBM or sham treatment groups. Subjects received PBM or sham treatment with the LT-300 light delivery system during 9 treatment sessions over 3-4 weeks with a second series initiated 6 months from baseline (BL). The LT-300 uses a multi-wavelength treatment comprised of 590 nm, 670 nm and 850 nm applied to the subject’s eyes for a total of 4-5 minutes per treatment per eye. This double-masked, randomized, sham-controlled study evaluated changes in clinical (visual acuity (VS) and contrast sensitivity (CS)) and anatomical (central drusen thickness and volume) endpoints. Quality of Life (QoL) was also assessed using the Visual Function Questionnaire-25 (VFQ-25).

Results : A total of 46 eyes were evaluated from 30 subjects. Subjects were enrolled with AREDs categories 2, 3 and 4. The mean Baseline ETDRS VA letter score was 74. An Interim analyses conducted at 3 months demonstrated improvement in VA and CS and reductions in drusen volume and thickness (p<0.05, linear mixed effects model using ranks). Subjects were further categorized into high (HV) or low vision (LV) groups based on BL scores. PBM-treated HV subjects demonstrated the greatest improvement in VA letter score (5.6 letters, p < 0.05) at 3 months. Statistically significant improvements in the VFQ-25 composite score (mean change from BL, 7.89, p = 0.003, CI: -12.61;-3.17) and in selected QoL questions were observed. The final findings of the LIGHTSITE I study will be discussed.

Conclusions : The LIGHTSITE I findings demonstrate that PBM improves clinical outcomes, provides anatomical benefits, enhances QoL and should be considered as a therapeutic treatment option for dry AMD patients.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.