Rho kinase inhibitors are a new class of glaucoma drugs currently in clinical trials. Rho kinase (dubbed “ROCK”) inhibitors promise to act specifically on the eye’s drainage canals (called the trabecular meshwork) a main outflow and blockage site in glaucoma.
Primary Open Angle Glaucoma is the most common type of glaucoma. Patients with glaucoma experience an increase in eye pressure, called intraocular pressure (IOP), which occurs slowly over time and leads to vision loss.
Higher pressure is thought to be the result of changes in the eye that lead to an obstruction in the outflow of fluid. Reducing pressure slows or minimizes retinal damage and progressive visual loss.
Current drug treatments are directed towards reducing pressure. Treatments to reduce IOP rely on topical eye drop medications or surgery. Many patients require more than one drug to control IOP, and despite effective current therapies, they don’t work for all patients.
Current glaucoma medications reduce IOP by either reducing the production of fluid in the eye or by increasing its outflow. Prostaglandins, which increase outflow, are now the most prescribed glaucoma treatment worldwide.
This new class of glaucoma drugs currently being tested promises to act specifically on the eye’s drainage canals, a main outflow and blockage site in glaucoma. These Rho kinase (ROCK) inhibitors target cells in the trabecular meshwork to enhance outflow and thus reduce pressure.
In research models of glaucoma, ROCK inhibitors have been shown to reduce cellular “stiffness” and enhance outflow through the trabecular meshwork, thereby reducing IOP. No drugs currently on the market enhance the eye’s fluid outflow in just this way. Therefore this is a novel and unique approach to lowering IOP which may be more effective than current medicines or which may work in patients who are not seeing results from prostaglandins.
ROCK inhibitors are not yet approved and available for glaucoma patients. Two US companies, Aerie and Altheos, are currently in early clinical trials and ophthalmologists are awaiting the data.