Glaucoma is a potentially blinding condition if it is left untreated. Treatment for glaucoma consists of lowering eye pressure by various means, and medication eye drops are the most commonly used method.
However, even with treatment, there is risk of not using the medications regularly because of various factors such as difficulty putting drops in the eye as well as side effects and cost of medications. If treatment is not regular, the eye pressure is not well controlled and this increases the risk of damage to the optic nerve.
Challenges with Adherence
The average patient with glaucoma has three other chronic diseases for which he/she takes 4 -5 additional medications. Thus, the barriers to continuing regular medical treatment in patients with glaucoma may be quite significant. A published study identified 71 different obstacles to medication adherence in patients with glaucoma. For these reasons, new medication delivery systems for glaucoma would be a welcome addition to our treatment options.
On the Eye, In the Eye, Around the Eye
The basic idea of drug delivery systems for glaucoma is to apply, insert, or inject medication to the eye that will release over weeks or months. Various delivery approaches are being developed that can be categorized as: on the eye, in the eye, and around the eye.
- On the eye: sophisticated new gel drops, contact lenses, or other technologies that release a steady amount of medication over time
- In the eye: implants that release drug over longer periods, requiring less total amount of medication, thus fewer side effects
- Around the eye: punctal (tear duct) plugs that release medication over time in a relatively non-invasive manner
New Horizons in Drug Delivery
On February 7, 2020, the Glaucoma Research Foundation hosted its annual Glaucoma 360 New Horizons Forum in San Francisco. One of the exciting symposium sessions addressed the topic of “New Medication Delivery Systems for Glaucoma.” This discussion highlighted advances in science and medicine that are enabling a whole range of new technologies to deliver anti-glaucoma medications in a more convenient, efficient, and effective manner.
These new options include but are not limited to: implantable extended-release devices, polymer-based contact lens and intraocular delivery technologies, drug-eluting punctal plugs, microneedle-injection devices, and micro-dosing technology.
The anticipated promise is that these new medication delivery systems will further enhance quality of life for patients, as well as provide more effective therapies to better preserve vision in glaucoma.
Article by James C. Tsai, MD.
Posted on March 1, 2020; Last reviewed on March 9, 2022.