Zioptan Receives FDA Approval for Patients with Open-Angle Glaucoma and/or Ocular Hypertension By Loretta Fala, Medical Writer
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laucoma is a group of chronic eye diseases that cause irreversible damage to the optic nerve, which leads to serious vision loss and blindness.1 Often associated with increased intraocular pressure, glaucoma affects an estimated 2.2 million people in the United States.1 The population affected by glaucoma is expected to increase to nearly 3 million people by 2020.1 Moreover, glaucoma is projected to become more prevalent as the aging US population increases.2
Glaucoma: Overview Although there are several types of glaucoma, open-angle glaucoma and angle-closure glaucoma are the 2 main types.3 Other types of glaucoma include normal-tension glaucoma, congenital glaucoma, and several variant forms of the open-angle and angle-closure type, such as secondary glaucoma, traumatic glaucoma, neovascular glaucoma, and others.3 Open-angle glaucoma is the most common type, accounting for approximately ≥90% of all glaucoma cases in the United States.3 Glaucoma is a leading cause of blindness in the United States, accounting for approximately 11% of all cases of blindness.4,5 Blindness resulting from glaucoma is 6 to 8 times more prevalent in blacks than in whites.4 In fact, open-angle glaucoma accounts for 19% of all blindness among blacks compared with 6% of blindness in whites.4 Moreover, the risk of visual impairment is 15 times higher in blacks than in whites.4 Glaucoma is particularly devastating, given its potential to destroy retinal ganglion cells (RGCs) in the optic nerve, which subsequently leads to permanent vision loss.1 Based on recent evidence, increased intraocular pressure may prevent RGCs from receiving a brain- derived neurotrophic factor, a protein required for RGC survival, from nearby cells in the optic nerve.1 Approximately 70% of patients with glaucoma have a history of elevated intraocular pressure.1 An elevated baseline intraocular pressure has consistently been established as one of the only modifiable risk factors associated with open-angle glaucoma. Other potentially modifiable factors, including intraocular pressure fluctuation and nutrition, are also being researched.6 Vision loss imposes a substantial societal and econom-
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ic burden for many people in the United States, which results in disability, suffering, and loss of productivity.7 Glaucoma has a detrimental effect on a person’s quality of life—including an effect on driving, walking, and reading—and it also may lead to social withdrawal and depression.2 The economic burden of glaucoma increases as the disease progresses.2 In the United States, glaucoma accounts for an estimated $2.9 billion annually in direct costs alone; this total cost is likely an underestimate, given that many patients with glaucoma are unaware that they have the condition.2,8 Glaucoma remains underdiagnosed and misunderstood.2 Individuals with glaucoma may remain undiagnosed, because the disease is relatively asymptomatic, particularly in the early stages, and a person may not seek medical attention until a bilateral field loss of vision occurs.2 In addition, many patients with diagnosed glaucoma are not receiving treatment.2 Over the past decade, substantial strides have been made in understanding and treating glaucoma.1 The Early Manifest Glaucoma Trial, a 6-year collaborative study, reinforced accumulating medical evidence showing that reducing eye pressure in the early stages of glaucoma slowed the disease progression.1,9 The Ocular Hypertension Treatment Study, an important study that included 1636 participants, showed that topical ocular hypotensive therapy delayed or prevented the onset of primary open-angle glaucoma in patients with elevated intraocular pressure, reducing the development of primary open-angle glaucoma by >50% (P <.001).10 A follow-up to that study showed that the use of daily topical ocular hypotensive therapy reduced the development of primary open-angle glaucoma in black patients by nearly 50% (P = .02).11 Improved screening and diagnostic techniques have led to more precise visual assessment tests. The recent development of prostaglandins, a new class of drugs that provides intraocular pressure control with fewer side effects, has further improved the management of glaucoma.1
Zioptan Receives FDA Approval In February 2012, the US Food and Drug Administration (FDA) approved Zioptan (tafluprost ophthalmic solution 0.0015%; Merck & Co), a preservative-free
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