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64 EW GLAUCOMA February 2011 2013 Glaucoma editor���s corner of the world New technology could improve eye drop delivery by Ellen Stodola EyeWorld Staff Writer E ye drops are a frustrating, clumsy, and imprecise way to deliver ophthalmic medications. But despite all their ���aws, eye drops have been extremely dif���cult to supplant and remain the dominant delivery technology. That may be about to change, and this month���s ���Glaucoma corner of the world��� pro���les a topical delivery technology that could revolutionize the administration of ophthalmic medications. We are very fortunate to have Sean Ianchulev, M.D., and Mark Packer, M.D., describe this new device. Alan Robin, M.D., who has immense experience with topical medications and their problems, discusses what a new technology needs to do to be effective. The new system seems to be a great advancement in being able to deliver a small amount of drug in a small volume that is accurately targeted at the eye. Previous studies have shown that small volumes with higher concentrations can achieve greater ef���cacy with fewer side effects. The new technology takes advantage of this principle and couples it with a targeting system that can deliver the medication accurately and faster than a blink. Another improvement made possible by this system is the ability to track and document compliance���or the lack thereof. One of the biggest hurdles to technology advances in eye drop delivery is cost. A disturbing trend in topical therapy is the increasing prevalence of ultra-low cost bottles. These bottles allow uncontrolled delivery of medication, and the entire contents can be expressed with just a few ���rm squeezes. Although the bottle is inexpensive, the uncontrolled delivery may eventually wind up costing the patient much more. But any new delivery system will require an initial investment in retooling expenses and be a paradigm shift in how topical drugs are dispensed. Hopefully, a new technology that delivers drops more effectively, more safely, and more accurately���while also tracking compliance���will ultimately triumph in the marketplace. Reay Brown, M.D., glaucoma editor T he eye dropper is a technology that has changed relatively little over time, but many doctors have recently seen a need to adapt the device to make it more effective for patients attempting to use it to administer medications. Sean Ianchulev, M.D., clinical associate professor, University of California, San Francisco, recently presented on results of a study for the new eye droplet device being developed by Corinthian Ophthalmic (Raleigh, N.C.). The new delivery system would work to remedy some of the obstacles to patients trying to use eye droppers as a means to deliver medication to the eyes. Mark Packer, M.D., clinical associate professor of ophthalmology, Oregon Health & Science University, Portland, also worked on the findings for the new technology. Meanwhile, Alan L. Robin, M.D., associate professor of ophthalmology and international health, Johns Hopkins University, Baltimore, weighed in on what an eye drop delivery system would need to do to be effective. Problems with current technology ���If you look at the history of people trying to develop alternatives to eye drops, this is not new,��� Dr. Ianchulev said. Over the years, people have explored sprays and other ways to get drops or medication inside the eye because of the challenges associated with the eye dropper. One of the major issues, Dr. Ianchulev said, is overdosing; this can cause problems with preservative overexposure of the ocular surface or in the case of topical betablockers, systemic side effects such as shortness of breath, depression, fatigue, and dizziness. Another problem is that people often blink while trying to use eye drops or cannot instill them directly into the eye. Compared to oral or intravenous drug delivery, topical eye drops are notoriously challenging in terms of dosing accuracy. What physicians prescribe is actually quite different from what people get. ���Eye drops have been around for hundreds of years,��� Dr. Robin said. ���They are a lousy delivery system for many reasons.��� He said eye drops pose a problem for those who Corinthian Ophthalmic's Whisper device spray gives smaller doses than a generic eyedropper, with controlled dosing and ejection for better accuracy of administration. rely on caregivers to administer eye drops for them. He also cited problems of getting a drop into the eye. the accuracy and efficacy of delivery,��� he said. What a new system needs Though still in research and initial stages, Dr. Ianchulev said results so far have been encouraging. ���I think it was surprising to us, the results that we saw,��� he said about presenting some of the first human data. Results from just over 100 people compared dilation between the new technology and the current eye drop method. Dr. Packer said with the pupil dilation study it was not exactly clear what size dose would work best, so it was tested with the microdroplets of 1.5 microliters, 6 microliters, and two sprays of 3 microliters each. He said all of these quantities showed effective dilation. Dr. Robin said there several things a new system would need. ���It has to be relatively inexpensive,��� he said. ���It has to be reusable so that you can put any bottle in it,��� he said, referring to one system that would take a variety of medications and refills. He said the medicine would also have to be able to be administered to the patient without getting contaminated. Dr. Robin highlighted the importance of a patient being able to use the system with ease. ���It has to have some guidance system, a focusing light or something that would allow patients to aim it on their eyeball,��� he said. There would need to be a way of administering a specific amount and making sure it gets to the eye, he said, as well as a way to keep the eye open. The new technology Dr. Ianchulev said with the new technology, one focus has been improving the directionality of the flow. In addition, speed is something that was considered with the new droplet technology. He said the speed of delivery is faster than the blink rate, which would allow the medication to get to the eye before a person has the chance to blink. The LED display improves positioning and targeting. ���They solve a lot of the issues of how to deliver medication to the eye and improve Examining initial results Interest in the technology Dr. Ianchulev said the new technology is not yet commercially available anywhere; in terms of when it will become available, he said it will likely be different for each country. ���The company is working on collaborations with the different pharmaceutical companies so they can formulate or package their eye drops with this new technology,��� he said. ���This is the only technology since several hundred years ago when people invented the eye dropper, and we know the eye dropper has major challenges,��� Dr. Ianchulev said. ���So if you���re a pharmaceutical company, especially in a very competitive space, that wants to have a better technology out there and a differentiated technology, this could