In this prospective study conducted by multiple ophthalmic surgeons at a single investigational site, 101 phakic subjects with primary open-angle glaucoma that had not undergone prior glaucoma treatment of any kind were randomized in a one-to-one ratio to receive either two iStents in a standalone procedure or topical ocular hypotensive medication therapy (travoprost). Phakic refers to eyes that have not undergone prior cataract surgery and contain a natural lens. The study is designed for follow-up of all subjects through five years. Through 36 months, study results showed:
Mean IOP in the stent group (n=39) declined 43 percent from 25.5 mm Hg to 14.6 mm Hg, while mean IOP in the travoprost group (n=34) declined 39 percent from 25.1 mm Hg to 15.3 mm Hg.
Eleven percent of eyes in the stent group required additional topical medication therapy, compared to 23 percent in the travoprost group.
Ninety-one percent of eyes in the stent group had IOP ≤ 18 mm Hg without additional topical medication therapy, compared to 79 percent of eyes in the travoprost group; 62 percent of eyes in the stent group had IOP ≤ 15 mm Hg without additional topical medication therapy, compared to 21 percent of eyes in the travoprost group.
“We embarked on this study to assess the potential utility of iStent as an initial treatment in naïve open-angle glaucoma patients versus topical travoprost, which is a commonly prescribed first-line medication therapy,” said Steven D. Vold, M.D. “Three-year safety and efficacy data are promising and show that two iStents achieved sustained IOP reduction, with fewer subjects requiring additional topical medication therapy compared to topical travoprost. These results indicate that iStent implantation as initial therapy in newly diagnosed glaucoma patients may be a viable alternative to topical ocular hypotensive medications, which are often associated with high rates of non-compliance, side effects and/or ocular surface damage.”
Approved by the U.S. Food & Drug Administration (FDA) in 2012, iStent is indicated for use in the United States in conjunction with cataract surgery for the reduction of IOP in adult patients with mild-to-moderate open-angle glaucoma currently treated with ocular hypotensive medication. The iStent is the industry’s first Micro-Invasive Glaucoma Surgery (MIGS) device. It is inserted from within the anterior chamber through the trabecular meshwork and into the eye’s drainage canal, known as Schlemm’s canal, where it is designed to restore the natural physiological outflow of aqueous humor. Made of surgical-grade non-ferromagnetic titanium that is coated with heparin, the iStent is approximately 1.0 mm long and 0.33 mm wide. Glaukos believes it is the smallest medical device ever approved by the FDA.
The company’s next-generation MIGS device, the iStent inject Trabecular Micro-Bypass Stent includes two stents preloaded in an auto-injection mechanism that allows an ophthalmic surgeon to inject stents into multiple trabecular meshwork locations through a single corneal entry point. The iStent inject has been approved in the European Union, Australia, and Canada. The iStent inject is for investigational use only in the United States, with two IDE clinical trials underway for two versions of the product, one for use in conjunction with cataract surgery and another for use as a standalone procedure.
Glaucoma is characterized by progressive, irreversible and largely asymptomatic vision loss caused by optic nerve damage. There is no cure for the disease and reducing IOP is the only proven treatment. According to Market Scope, more than 80 million people worldwide have glaucoma, including 4.5 million people in the United States. Open-angle glaucoma is the most common form, affecting approximately 3.6 million people in the United States.
Glaukos develops and commercializes breakthrough products and procedures to treat glaucoma, one of the world’s leading causes of blindness. The San Clemente, Calif.-based company pioneered micro-invasive glaucoma surgery, or MIGS, to revolutionize the traditional glaucoma treatment and management paradigm. Glaukos launched the iStent, its first MIGS device, in the United States in July 2012 and is leveraging its platform technology to build a comprehensive and proprietary portfolio of micro-scale injectable therapies designed to address the complete range of glaucoma disease states and progression.