Eyeworld

46 August 2016 EW REFRACTIVE by Maxine Lipner EyeWorld Senior Contributing Writer improved after a few weeks," Dr. Chang said. "There was one patient who noticed it initially, but it did get better." While not mentioned in the pa- per, Dr. Chang is also concerned that the miotic effect may be noticeable especially for light-eyed patients. "If you put a drop in that shrinks the pupil, are people going to look at you funny?" he said. Use of the drop, however, is reversible. That means that if patients don't like it or the drop hurts, they can move on to the next option, he pointed out. "I think it's a good intermediate step with a low barrier to entry," Dr. Chang said. "Patients get a prescrip- tion, fill the drop, put it in, and if it works, great. If it doesn't, then they could think about inlays or lens exchange with presbyopic IOLs." Sherman Reeves, MD, part- ner, Minnesota Eye Consultants, those under age 50. "Our accommo- dation continues to deteriorate as we age," Dr. Chang said. "So I think for the younger patients there was a slightly less effect of change, but that's because they were better to begin with." The effectiveness of the bri- monidine/carbachol combination was in keeping with Dr. Chang's expectations. "Having heard of this kind of result with brimonidine, pilocarpine, and other combination therapies, I think it's interesting," he said, adding that when the time comes, he could see himself trying such medications off-label as a drop winds its way through the FDA. He does, however, have some minor concerns with the approach. "They did mention that there was a dull headache reported in 10% (of patients), and there was some difficulty in the luminosity that dropped to J4, and at 10 hours was at J5. The mean pupil size decreased significantly from a mean of 4.77 mm before treatment to 2.5 mm at 1 hour. At the 10-hour mark, this was at 3.81 mm. Meanwhile, for those in the younger group, visual acuity likewise significantly improved from a mean of J6 before treatment to J2 at the 1-hour mark. By 10 hours after treat- ment, this had fallen to J5. Before treatment the mean pupil size was at 4.72 mm and 1 hour after was at 2.71 mm. By 10 hours the mean was 3.85 mm. The masked placebo group saw no significant difference in mean pupil size or near visual acuity. Distance acuity for all patients was at 20/20 prior to and throughout treatment. Investigators concluded that making the pupil smaller improves depth of focus, which in emme- tropic presbyopic patients signifi- cantly improves near visual acuity. They view the combination of brimonidine and carbachol as a safe and acceptable alternative to surgical presbyopia correction or traditional lenses. Daniel Chang, MD, Bakers- field, California, said using drops to alleviate presbyopia is an exciting approach and might provide an alternative for some. "I think there is amazing presbyopia technology including recently FDA-approved presbyopic IOLs like the Tecnis Symfony [Abbott Medical Optics, Abbott Park, Illinois] and corneal inlays, like the Raindrop [ReVision Optics, Lake Forest, California]," Dr. Chang said. However, he added, there are some people who don't want surgery or who don't want to do it yet for whatever reason, for whom the eye drop would be a com- pelling way of dealing with their presbyopia. "I think it's an elegant study that showed some nice prelimi- nary results," he said. One of the strengths here, in his view, is the fact that patients were separated into an older group of those age 50 and over and a younger group including Reviewing miotic approach to presbyopia N ew technology may not be the only way to com- pensate for the woes of presbyopia. Innovative miotics may provide a pharmacologic option for those who prefer to avoid surgical interven- tion. In a recent study published in Eye & Contact Lens, 1 investigators considered whether use of the alpha agonist brimonidine together with the parasympathomimetic drug carbachol might result in miosis, which could help lessen the effects of presbyopia. EyeWorld asked 2 leading prac- titioners to consider the study and share their impressions here. The aim of the prospective, randomized placebo-controlled clinical trial was to determine whether presbyopia could be alleviated with the aid of miosis created by using carbachol in conjunction with brimonidine. Included in the study were 48 subjects between the ages of 43 and 56 who were both emmetropic and presbyopic. Investigators divided subjects into 2 groups. The 30 eyes in the "treatment group" received 0.2% brimonidine eye drops in conjunction with a dose of 2.25% carbachol. Meanwhile, the 18 eyes in the control group received place- bo drops. All drops were placed in the non-dominant eye in a masked fashion. Investigators found a statistical- ly significant improvement in near acuity for all who had received the brimonidine in conjunction with the carbachol. This was not true for any who were given the placebo. In- vestigators saw nothing to indicate that tolerance toward the drops was developing during the study period. After each group was subdi- vided into those age 50 and older and those under 50, investigators found that the older group's mean near acuity improved from J7 before instillation of the drops to J3 at 1 hour after usage and remained there at the 2-hour mark. At 4 hours this Close-up on presbyopia study Drops on the horizon T he non-surgical, miotic approach has some definite investigative steam. Currently there are 3 different miotic drops in clinical trials, according to Preeya Gupta, MD, assistant professor of ophthalmology, cornea and refractive surgery, Duke University Eye Center, Durham, North Carolina. These include EV06 (Encore Vision, Fort Worth, Texas), PRX-100 (Presbyopia Therapies, Coronado, California), and PresbV Tears (Popayán, Colombia). While some of these are just in phase 1 trials, preliminary results for the 3 are promising. "They're showing that patients have much improved corrected near and intermediate vision without distance compromise," Dr. Gupta said, adding that such compromise has previously been a concern with some pupil-constricting agents, which have left patients with reduced peripheral vision and poor overall quality acuity. With these agents being studied, however, pupil constriction alone is stimulated, without involving accommodation; this limits the compromise in distance acuity, she explained. Overall, she is very excited about this medical option, pointing out that as little as 1 drop a day may ultimately be needed for presbyopia assistance. Editors' note: Dr. Gupta has no financial interests related to her comments. Contact information Gupta: preeyakgupta@gmail.com Pharmaceutical focus

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