LumiThera Presents New Data from LIGHTSITE III Trial Showing Improvement in Vision in Intermediate Dry AMD
LumiThera announced detailed findings in its LIGHTSITE III, multicenter clinical trial in non-neovascular age-related macular degeneration (AMD) subjects treated with photobiomodulation (PBM) using the Valeda Light Delivery System.
LIGHTSITE III, a prospective, double-masked, randomized, multicenter clinical trial, was conducted at 10 US retinal centers. The objective was to treat non-neovascular (dry) AMD subjects with PBM every 4 months for a duration of 24 months. One hundred subjects were enrolled in a 2:1 ratio of PBM to sham in the treatment groups. The mean age was 75 years and mean dry AMD duration since diagnosis was 4.9 years prior to trial enrollment. Baseline best corrected visual acuity (BCVA) letter scores observed were a mean +SEM of 69.4+0.8 and 70.1+0.7 in the sham and PBM treatment groups, respectively. The majority of subjects were considered to have intermediate dry AMD. The analysis included 91 eyes in the PBM treatment group and 54 eyes in the sham treatment group in the modified intent to treat population.
The trial results demonstrated statistically significant improvement in the prespecified primary endpoint in BCVA at 13 months in the PBM treatment group over the sham-treatment group (P=0.02). A sustained, mean increase in ETDRS letter score of ~5.5 letters from baseline was seen at the 13-month timepoint in PBM-treated subjects (P<0.0001). In the PBM treatment group responders, 55% of the subjects showed a >5 letter improvement on the standard EDTRS eye chart with a mean of 9.7 letters and 26% achieved a >10 letter improvement with a mean of 12.8 letters.
In addition to improvements in BCVA, anatomical measurements in PBM-treated subjects demonstrated no significant increase in drusen pathology at 13 months compared to baseline, while sham subjects continued to see numerical increases in drusen deposition. Drusen deposition is the hallmark pathology for diagnosis of dry AMD which leads to chronic inflammation and is associated with disease progression and cell loss. A negative correlation was observed between lower drusen volume pathology and improvement in BCVA with PBM (Spearman correlation, -0.3, P=0.004).
The advance to later stage disease pathology such as the neovascular (wet) form or the development of geographic atrophy (GA), i.e., loss of retinal tissue in naïve patients was evaluated. The percentage conversion of dry AMD to the wet form was 1.8% for sham, 5.4% for PBM, and 8.3% for the non-study eye groups at month 13. A few patients had GA (9 eyes at screening), and were distributed evenly between 5 PBM and 4 sham eyes at baseline. At month 13, 6 additional eyes progressed with new GA identified. Overall, a total of five of 55 sham eyes progressed to new GA (9.1%) versus only 1 of 93 PBM eyes progressed to new GA (1.1%) at month 13.
“The subjects had good starting vision with approximately 70% having between 20/32 to 20/40 vision. Study subjects were only enrolled in the study if their vision was 20/32 to 20/100 and no evidence of GA in the central macula,” Diana Do, MD, and Quan Dong Nguyen, MD, MSc, FARVO, Professors of Ophthalmology and members of the Retina Division at the Byers Eye Institute at Stanford University, a clinical site for the LIGHTSITE III trial, stated in a company news release. “Intermediate dry AMD patients have pathology and visual impairment consistent with earlier stages in the disease and have not lost retinal tissue by progressing to GA. Thus there is an opportunity to improve their vision while retinal tissue is still viable. Therapy with PBM using the Valeda Light Delivery System may serve a significant unmet need for many of our patients with dry AMD who now have the potential to improve their visual acuity with treatment.”
“The safety results from the LIGHTSITE III trial through the 13-month timepoint were excellent,” stated René Rückert, MD, MBA, Chief Medical Officer, LumiThera. “We now have patients that have exited the 2-year study. We will continue to follow all patients for the full 24 months for safety. To date the results are consistent with a very favorable safety profile and a noninvasive treatment that can target patients earlier in disease.”
“Overall, the clinical results show improvements in vision; what is further interesting is the lack of drusen deposit in the PBM treated group, and potentially less patient conversions to wet form of disease,” said Glenn Jaffe, MD, Robert Machemer Professor of Ophthalmology; Chief, Vitreoretinal Division and Director, Duke Reading Center, the central imaging center for the LIGHTSITE III study. “Patient progression to new GA was also evaluated and was less in the PBM group, and while the new GA progression numbers are small in this study group, all outcomes point in favor for PBM as a novel approach to treat dry AMD patients earlier in disease.”
The LIGHTSITE III data is being presented at the 34th International Congress of German Ophthalmic Surgery (DOC) taking place in Nuremberg, Germany from June 23–25th. The LIGHTSITE III data will also be discussed at the OIC/WAVE 22 retina conference being held in Vail, Colorado from June 22-25, 2022.