Photobiomodulation (PBM) can improve visual function and mitochondrial output, and may reduce the volume of macular drusen in patients with intermediate-stage, nonexudative, dry age-related macular degeneration (AMD), according to a study published in Ophthalmology and Therapy.
Investigators conducted a multicenter, randomized clinical trial, LIGHTSITE II (ClinicalTrials.gov Identifier: NCT03878420) to investigate the effects of PBM on clinical, quality of life, and anatomical outcomes in patients with intermediate-stage, nonexudative AMD. PBM therapy employs wavelengths of light in the 500 nm to 1000 nm spectrum “to activate components of the electron transport chain in the mitochondria,” according to the report. “Improvements in mitochondrial output and subsequent cellular functioning may improve clinical outcomes in non-exudative AMD.”
The team delivered multiwavelength PBM (590, 660 and 850 nm) or sham treatment 3 times per week for 3 to 4 weeks (9 treatments per series) with repeated treatments at baseline and 4 and 8 months. The primary efficacy endpoint was the change from baseline in best-corrected visual acuity (BCVA) among photobiomodulation-treated eyes at month 9.
A total of 53 eyes of 44 patients (mean age, 74.1±8.0 years; 61.4% women and 38.6% men; 77.3% non-Hispanic White) were included in the study. There were 32 eyes in the photobiomodulation group, with a mean BCVA of 70.06±5.76 letters and 19 eyes in the sham group, with a mean BCVA of 70.53±5.02. letters.
Among patients who received all treatments, the investigators report significant improvement in BCVA from baseline to month 9 in the photobiomodulation-treated eyes (4-letter gain; P =.02) but not the sham-treated eyes (0.5-letter gain; P <.10). Approximately 35.3% of photobiomodulation-treated eyes showed 5-letter improvements or better at 9 months. Investigators report no safety concerns of signs of phototoxicity.
“These results build on previous clinical testing of multiwavelength PBM and support continued investigation into its potential as a novel treatment for non-exudative AMD,” according to the investigators.
Limitations of the study included interference from the COVID-19 pandemic, which interrupted adherence to the proposed protocol, data collection and statistical analysis. With only 44 enrolled patients, the study underpowered and was considered a feasibility study.
Disclosure: This research was supported LumiThera, Inc. Please see the original reference for a full list of disclosures.
Burton B, Parodi MB, Jürgens I, et al. LIGHTSITE II randomized multicenter trial: evaluation of multiwavelength photobiomodulation in non-exudative age-related macular degeneration. Ophthalmol Ther. Published online January 2, 2023. doi:10.1007/s40123-022-00640-6