A recent study investigated the effects of photobiomodulation (PMB) on the clinical, anatomical, and quality of life (QOL) outcomes in patients diagnosed with intermediate stage non-exudative age-related macular degeneration (AMD).
First, talk about photobiomodulation.
Photobiomodulation (PBM) is a form of light therapy that uses red or near-infrared light (500 to 1,000 nm) to potentially regenerate, heal, and reduce inflammation for chronic and acute pain.
Benefits from the use of PBM have previously been observed post-op treatment that mirror the causes of non-exudative (dry) AMD, including inflammatory and mitochondrial distress.
Now tell me about the study.
The multicenter, LIGHTSIGHT II study (NCT03878420) was a randomized clinical trial meant to evaluate the safety and efficacy of PBM in intermediate non-exudative AMD.
Researchers analyzed the use of the LumiThera Valeda Light Delivery System—a medical device that delivers three wavelengths of PBM: 590, 660, and 850 nm—or sham treatment, three times a week over the course of 3 to 4 weeks (9 treatments per series). Treatments were repeated at baseline as well as at 4 and 8 months.
I need more info on the patients.
All study participants were enrolled (if meeting the inclusion criteria) with 20/32 and 20/100 best-corrected visual acuity (BCVA) and with no central geographic atrophy (GA) within the central fovea (500 μm).
A total of 44 subjects (53 eyes) were studied with 61.4% (n = 27) of the participants being female. The average age was 74.5 years old.
Any major challenges?
As the study was conducted during the COVID-19 outbreak, the researchers cited such challenges that included country-specific quarantines, closures, travel limitations, and infections among participants and study personnel that ultimately led to issues with protocol-specified procedures and timelines. See here for more details.
What were the findings?
Eyes treated with PBM exhibited a statistically significant BCVA improvement at 9 months (n = 32 eyes, p = 0.02). Patients that received all 27 PBM treatments (n = 29), there was a 4-letter gain in the PBM-treated group compared to a 0.5-letter gain in the sham-treated group (ns, p < 0.1).
A ≥ 5-letter improvement was observed at 9 months for an estimated 35% of PBM-treated eyes. Additionally, GA lesion growth was observed during the trial period in both PBM and sham groups; however, the PBM group experienced 20% less growth over 10 months.
Researchers also reported no signs of phototoxicity or safety concerns.
As the first randomized, controlled clinical trial using the Valeda system in patients with non-exudative AMD, the study authors concluded the results support previous clinical testing of PBM as a novel treatment.
However, they noted that further study is needed to develop “an optimized approach for the PBM delivery and treatment intervals specific to ocular indications.”