The Use of Photobiomodulation (PBM) in the Treatment for Diabetic Macular Edema

ABSTRACT Diabetes affects over 284 million people worldwide and 20% of diabetic patients develop diabetic macular edema (DME), a significant ocular complication that impairs visual function, eventually leading to blindness if left untreated. For patients with DME, current treatment involves laser photocoagulation surgery and intravitreal anti-VEGF injections, which are invasive and expensive procedures. Photobiomodulation (PBM) therapy consists of exposure to low levels of light radiation to targeted tissues resulting in beneficial effects to mitochondrial output and improvements in clinical outcomes. Dry age-related macular degeneration (AMD) shares overlapping pathology with DME including mitochondrial dysfunction and inflammation leading to significant vision loss. Several pilot studies in Dry AMD, e.g., TORPA I and II, LIGHTSITE I, have shown improvements in both visual and anatomical endpoints following PBM treatment. In the most recent LIGHTSITE I study, clinically and statistically significant improvement in visual acuity and contrast sensitivity, reductions in drusen thickness and drusen volume, and improvements in activities of daily living were observed immediately after PBM treatment. PBM treatment was administered using multiple pre-selected wavelengths to stimulate mitochondrial function and to suppress VEGF expression with the Valeda® Light Delivery System. Valeda is the only commercially approved device (CE mark) for dry AMD treatment.The current SBIR proposal aims to expand the utility of the Valeda treatment into the DME population and conduct a pilot prospective, double-masked clinical trial with LumiThera’s Valeda Light Delivery System, with two top retinal DME centers: Stanford (PI: Drs. Diana Do and Quan Nguyen) and the New York Eye and Ear Infirmary (NYEE, PI: Dr. Richard Rosen). Both centers have experience with the Valeda device, and the Study Specific Aims will establish the magnitude of clinical, anatomical and metabolic benefit of multi-wavelength PBM on 40 DME patients, divided into two groups. Approximately 20 subjects will receive PBM treatment and 20 subjects will receive sham treatment 3x per week for 3 weeks using the Valeda Light Delivery System. Stanford University and NYEE provide top DME research environments to conduct this innovative, exploratory clinical trial. All subjects will be assessed for clinical (visual acuity and contrast sensitivity) and anatomical (OCT and OCT-A imaging) outcomes at baseline and Months (M) 1, 3 and 6 post-treatment. Metabolic outcomes (flavoprotein fluorescence) will be measured after each PBM treatment as well as at M3 and M6 to establish the time course of mitochondrial improvement and long-term duration of effect.The findings will provide the basic safety and scientific foundation for a pivotal trial with a novel non- invasive, non-pharmaceutical therapy for DME.