Eyeworld

79 EW GLAUCOMA February 2017 follow-ups are essential to separate the few who are destined to have se- vere vision loss from the many who will do better, based largely but not completely on genetic factors. Patients are more likely to be noncompliant with glaucoma reg- imens if they can't afford their medi- cines, have memory issues and can't remember to take them, or have trouble instilling the drops because of arthritis, Dr. Singh pointed out. Sustained-release vehicles Taking the patient out of the equa- tion can circumvent even the most difficult compliance issues. Current- ly, there are a host of sustained drug delivery systems in the pipeline. Among these, Dr. Lewis mentioned the bimatoprost SR implant (Aller- gan, Dublin, Ireland). "It is injected into the anterior chamber and lasts 4 to 6 months," he said. "Envisia Therapeutics [Durham, North Car- olina] has a similar type of system using travoprost." In addition, there are two punctal plugs, one by Mati Therapeutics (Austin, Texas) and the other by Ocular Therapeutix (Bedford, Massachusetts), under de- breaking it down to morning, lunch, dinner, and bedtime. "There are some apps that they can get on their phones that will remind them," Dr. Lewis said. In addition to having that kind of checklist, if the regimen is rather involved, another possibil- ity is to have a staff member follow up with occasional calls, although this can be expensive and time-con- suming. Dr. Singh advises showing patients measurable progression of their disease that puts them at risk for vision loss to motivate them to take their medications. "I think there are many strategies that we use," he said. "The one that strikes me as most effective is to show them their vision loss—to demonstrate to them that they have a visual deficit that's related to their disease." What you can't do, however, is promise that compliance will help stop their disease progression, Dr. Singh said. While there are data showing that treatment is better than non-treat- ment, there is none showing that you can completely halt the disease. One factor that can foretell how likely a patient is to adhere to the regimen is severity of the disease. Dr. Singh cited a study he conducted with others that showed that if pa- tients have symptoms of glaucoma- tous disease, they're more likely to take their medications. 2 "Somehow, many have ignored this very basic fact relating to glaucoma, which we find for many other diseases as well," he said. "If patients are not convinced that they have a disease and particularly if they are asymp- tomatic, they are far less likely to take medicine for that disease." Like- wise, those with more severe disease are more likely to be the ones com- ing in regularly for follow-up. He cited another study he worked on where people who had gotten worse over the prior 2 years were the ones who weren't coming in regularly. 3 "Some patients who are compliant with therapy but skip follow-ups— due to a false sense of security that by taking their treatment they don't need follow-ups—may be at high risk of vision loss as the medica- tions may not work or cease to work over time." The natural history of glaucomatous disease varies tremen- dously among patients, and regular velopment, Dr. Lewis said. These are loaded with a drug that is released at a sustained rate. In addition, there's a new ring from Alcon (Fort Worth, Texas) that sits on the sclera or the conjuncti- va and releases drug over a period of time, Dr. Lewis noted. There is also some discussion about placing the drug in contact lenses. There is a MIGS device that Glaukos (San Clemente, California) is working on that could potentially double for drug delivery. "It theoretically would be placed in through the trabecular meshwork into the canal," he said, adding there it would help the tra- becular flow as well as deliver a drug. Dr. Singh categorized such devices based on whether they will be internal or external. "I'm more optimistic about the external ap- proaches than intraocular drug de- livery, particularly for patients who have mild to moderate disease and are asymptomatic. Even the small risk of intraocular injection may be too much for those with the earliest stages of disease, particularly given Dr. Chauhan's study showing how slowly the disease generally pro- gresses in a real-world situation." Dr. Singh is skeptical that patients who are noncompliant with drops would be willing to have needles periodi- cally put in their eyes. "They might be more willing to take an external delivery device that's noninvasive," he said. EW References 1. Chauhan BC, et al. Practical recommen- dations for measuring rates of visual field change in glaucoma. Br J Ophthalmol. 2008;92:569–573. 2. Ung C, et al. Glaucoma severity and medication adherence in a county hospital population. Ophthalmology. 2013;120:1150–7. 3. Ung C, et al. The association between compliance with recommended follow-up and glaucomatous disease severity in a county hospital population. Am J Ophthalmol. 2013;156:362–9. Editors' note: Dr. Lewis has financial interests with Aerie Pharmaceuticals (Irvine, California), Allergan, Alcon, Glaukos, and Ivantis (Irvine, Califor- nia). Dr. Singh has financial interests with Allergan and Ocular Therapeutix. Contact information Lewis: rlewiseyemd@yahoo.com Singh: kuldev.singh@stanford.edu

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