Photobiomodulation Using the Valeda Multiwavelength Light Delivery System Demonstrates Significant Reduction in Risk for Vision Loss and Onset of Geographic Atrophy in Dry Age-Related Macular Degeneration

Abstract

Purpose : The LIGHTSITE III study evaluated multiwavelength photobiomodulation (PBM) treatment using the LumiThera Valeda^® Light Delivery System in dry age-related macular degeneration (AMD).

Methods : LIGHTSITE III was a prospective, double-masked, randomized, sham-controlled, parallel group, multi-center study to assess the safety and efficacy of PBM in dry AMD. PBM therapy consists of low-level light exposure to selected tissues resulting in positive effects on mitochondrial output and improvement in cellular activity. Subjects were treated with six series of multi-wavelength PBM (590, 660 and 850 nm) or active Sham treatment (Tx) (3x per week/3-5 weeks) delivered every 4 months over a 24-month period. A cox proportional hazards model was performed to evaluate the time to event hazard ratio of 1) vision loss (defined as >5 letter loss in BCVA) and 2) onset of geographic atrophy (GA). Data was analyzed at 24 months.

Results : 100 subjects (148 eyes) with dry AMD were randomized. The majority of subjects had a mean age of 75.4 years (SD 7.1) and a mean time since diagnosis of 4.9 yrs. The LIGHTSITE III study results demonstrated a sustained improvement in BCVA with a primary endpoint BCVA benefit at both 13 and 24 months in the PBM vs Sham Tx group. The patients in the sham tx group showed greater vision loss over two years and progressed into later stage disease with 18% of sham eyes losing >5 letters in BCVA and 24% progressing to new onset GA. In the current analysis, the hazard ratio for BCVA with a >5 letter loss was 0.47, (p < 0.02) which indicated a statistically significant 53% reduction in onset of vision loss of >5 letters for PBM vs Sham Tx. The hazard ratio for onset of new GA was 0.27, (p < 0.006) indicating a statistically significant risk reduction of 73% to progress to new GA for PBM vs Sham Tx.

Conclusions : LIGHTSITE III provides the largest randomized controlled trial in dry AMD showing improved clinical and anatomical outcomes following PBM treatment. PBM therapy may offer a new treatment strategy with a unique mitochondrial mechanism and modality for patients with dry AMD to maintain retinal health and slow AMD disease progression.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.