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).
Anything else?
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.
Significance?
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.”