New Ways to Treat Glaucomaby Joseph Saling Health Writer
When found and treated early, glaucoma can be controlled and the disease progression slowed in many people who have it. But for others, treatment comes too late—or may not be effective.
Because untreated glaucoma can cause permanent blindness, research is a major priority within the glaucoma community. Here are some things to watch for in the next few years.
Overcoming treatment obstacles
In a paper published in 2016 in the journal Ophthalmology, researchers identified low patient adherence in using eye medications as a major obstacle to the effective management of glaucoma.
Low adherence, they said, could be attributed to such factors as forgetfulness, medication cost, and trouble with self-administering eyedrops. Even when adherence is not poor, mistakes in applying eyedrops—for example, using them too frequently—can lead to large gaps in their use between prescription refills.
Poor adherence and medication mistakes highlight the need for a self-dispensing system that does not require patient action to provide regular, long-term delivery of the necessary drugs. The authors had just completed a phase II study—part two of a four-part clinical trial—assessing the efficacy and safety of such a system.
It consists of a round, silicon ring manually inserted by a doctor who places it around the eye, fitting it into the arched structure behind the upper eyelid and just below the lower portion of the eye. The ring is designed to consistently deliver a daily dose of medication over a period of six months, at the end of which the ring is removed and replaced by a new one.
Results of the study showed that the insert significantly reduced intraocular pressure (IOP), was well tolerated by patients, and produced no major safety concerns.
The next step before the procedure becomes commercially available is to run a phase III study involving a larger group of people to confirm the procedure’s effectiveness, monitor side effects, and compare it to existing treatments.
Current research still focuses on finding better drugs and more effective ways to manage IOP by preventing or slowing the progression of glaucoma. But some researchers are looking beyond the tools needed for management and searching for a cure.
Curing glaucoma would mean restoring sight—which so far has been impossible. That’s because nerves associated with vision are part of the central nervous system (CNS).
Unlike peripheral nerves—such as the nerves in your hand—nerves in the CNS cannot repair or regenerate themselves after an injury, at least not yet. Here are some developments.
• Stem cell research. The Glaucoma Research Foundation recently posted an article, written by Alice Williams, M.D., and colleagues, outlining the potential for stem cells in treating glaucoma, including:
• Replacing damaged eye tissue, such as the cells in the mesh network that lets fluid drain from the eye to control IOP.
•Rebuilding damaged sections of the optic nerve to restore its ability to transmit visual information to the brain.
While there’s excitement about what might be accomplished with stem cells, major problems still need to be resolved. Stem cells will need to be manipulated to grow into tissue requiring restoration. The cells also have to be implanted correctly in order to make the proper connections with other cells and tissue.
Despite the obvious need for more research, some international clinics have offered unproven stem cell treatment for glaucoma, which can result in serious, dangerous side effects and vision loss.
Right now, there’s no proven treatment, and unless you are taking part in a well-designed, well-regulated clinical trial that you’ve discussed with your own doctor, you should avoid experimental treatments, which are likely to do more harm than good.
Besides working with stem cells, researchers are exploring other strategies for encouraging the regeneration of damaged tissue.
Some of those strategies include using antibodies to suppress the inhibition of nerve cell regrowth, creating nanofiber protein structures in which nerve tissue can regenerate, and implanting engineered cells that can support nerve fibers and produce chemicals that stimulate nerve growth.
An active glaucoma research community in the United States is conducting clinical trials and looking for participants to test new approaches to managing—and someday repairing—the damage resulting from glaucoma.
If you’re interested in such a trial, ask your doctor about the kind of study that might be right for you. To find out more about trials that are currently recruiting participants, take a look at the list at CenterWatch.