Rho kinase inhibitors for glaucoma treatment

Glaucoma is a progressive optic neuropathy characterized by the loss of ganglion cells and their axons, resulting in a distinctive appearance of the optic disc. Glaucoma is concomitant to visual loss and is the second leading cause of blindness in the world. The disease affected more than 60.5 million individuals in 2010 and is projected to reach 79.6 million by the year 2020. Glaucoma is almost always asymptomatic, particularly during the early stages, which is why it remains undiagnosed in up to half of the total cases in developed nations, with even higher undiagnosed rates in parts of the developing world. A major risk factor for glaucomatous visual field loss is elevated intraocular pressure (IOP), and several studies have shown that lowering IOP reduces the risk of glaucomatous progression. Eye drops, oral medications, laser therapy, and surgery have all been used to decrease IOP in glaucoma patients. Currently, there are five main classes of eye drops for IOP reduction: cholinergic (pilocarpine), β-blockers, α-agonists, carbonic anhydrase inhibitors, and prostaglandin analogs. However, for many patients, these medications in monotherapy do not effectively control IOP, and approximately half of patients with elevated IOP are trea ted by co-administration of two or more glaucoma medications. Further, all of these classes of eye drops present ocular and systemic adverse effects that can impair the effectiveness of the treatment. Therefore, researchers are currently searching for new IOP-lowering drugs. ABSTRACT