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A tabletop device that delivers various wavelengths of light therapy to the back of the eye to activate cellular function in people with intermediate dry age-related macular degeneration (AMD) demonstrated vision improvements over a 4.5-year period, even with an almost 2-year disruption in treatment, a new study showed.

The LIGHTSITE IIIB study of photobiomodulation, a noninvasive light therapy, showed that patients enrolled in the original phase 2/3 trial of the device had an average improvement of five letters in best-corrected visual acuity (BCVA) after 2 years of treatment.

After they paused treatment for about 20 months, they recovered the gains in vision achieved before the interruption, David Boyer, MD, of Retina-Vitreous Associates Medical Group in Southern California, told attendees at American Society of Retina Specialists (ASRS) 2015 Annual Meeting in Long Beach, California.

Recovery After ‘Intermission’

“The topline preliminary data highlights the fact that the photobiomodulation LIGHTSITE IIIB trial showed to maintain best-corrected vision over a 20-month period with no treatment and was able to restore back to their five-letter improvement,” Boyer said. LIGHTSITE IIIB is an extension of the original LIGHTSITE III study in which patients had six series of treatments over 2 years.

Photobiomodulation is a tabletop device that patients look into and delivers light-based therapy at three different wavelengths — 590, 660, and 850 nm — to the back of the eye. Treatments are delivered three times a week over 3 weeks, paused for 4 months, then repeated. The FDA last year approved the device. However, soon after the approval a “viewpoint” in JAMA Ophthalmology raised concerns that retina specialists needed more data before they could “confidently” recommend the treatment to patients.

“The treatment is fairly easy to do, but it’s very time consuming,” Boyer said. “That’s the biggest complaint the patients had.”

The LIGHTSITE IIIB study enrolled 63 eyes from the original LIGHTSITE III trial. In the IIIB study, patients resumed treatments with four series and 4-month pauses between each series. The 20-month intermission occurred because the treatment had not been FDA-approved by the end of the first study and for unspecified “financial reasons,” Boyer said.

In the original LIGHTSITE III study, the treated patients experienced an average improvement of between five and six letters on the Early Treatment of Diabetic Retinopathy Study (ETDRS) scale, starting from a baseline BCVA of 70.7 letters on average, or about 20/40 on the Snellen chart, and improving to about 20/32.

By the time they enrolled in the IIIB study, average baseline BCVA was 74.8, almost four letters better than upon enrollment in the original study, but a decrease of one letter from the end of the first study. After 13 months and four series of photobiomodulation treatments in the IIIB study eyes, BCVA had improved by one letter on the ETDRS scale, to the level achieved after the first study, Boyer said.

The sham group in the first study switched to photobiomodulation for the second. These 15 eyes on average lost 5.7 letters of vision after the 20-month treatment intermission, showed no improvement in BCVA after 13 months of treatment in the IIIB study, he said.

In the IIIB study, two thirds of patients (67.7%) on average had a more than a 10-letter improvement in BCVA at 4.5 years, Boyer said. About a quarter (25.8%) had a more than a 15-letter gain, and 16% had a greater than 17.2-letter gain.

The biggest gains in BCVA were observed in patients who had 20/40 vision or worse, Boyer noted.

Not for Every Dry AMD Patient

“I don’t think every person who has intermediate age-related macular degeneration by definition is a candidate for this treatment,” Boyer told Medscape Medical News. “This study gives us hope that we may take this group of patients who have some visual impairment because of the macular degeneration and be able to improve their vision.”

“If a patient has 20/40 or 20/30 vision, you have a better chance you’re going to get some visual improvement with this treatment,” he said.

The results “need to be verified by a much larger study,” Boyer added.

During discussion of the findings, Abdhish Bhavsar, MD, a retina specialist with Retina Consultants of Minnesota in St. Paul, Minnesota, raised a question about the visual acuity gains in the study.

“The median visual acuity was not clear in the data presented, but from my higher understanding of the data that have been published already, median visual acuity was quite low from what we would expect from our typical patients with noncenter involved geographic atrophy and dry age-related macular degeneration,” Bhavsar said. “A lot of us are concerned about regression to the mean.”

Boyer acknowledged to the attendees that the five-letter improvement “is not a lot, but when you start with vision of 20/25, you’re not going to get a lot of improvement.” In the patients who had 20/40 vision or worse, the average improvement was about seven letters, he said.

LumiThera funded the study. Boyer is an unpaid adviser to LumiThera.

Richard Mark Kirkner is a medical journalist based in Philadelphia.