The initial phase of the standalone iStent inject interventional, randomized, open label, multicenter clinical trial includes approximately 75 subjects randomized to receive either iStent inject or laser trabeculoplasty. In this initial phase, subjects will be followed for three months to evaluate safety.

The results of the initial phase are expected to form the basis for the company’s submission to the FDA for expansion of the trial into the pivotal phase, which will include approximately 425 additional randomized subjects and seek a primary outcome of intraocular pressure (IOP) reduction.

The standalone iStent inject features two micro-scale stents preloaded into an auto-injection system that allows an ophthalmic surgeon to inject stents into multiple trabecular meshwork locations through a single, self-sealing corneal entry point.

It is designed for use in phakic and pseudophakic open-angle glaucoma patients. Phakic refers to eyes that contain a natural lens, while pseudophakic refers to eyes in which the natural lens has been removed and replaced with an artificial lens.

In addition to the U.S. IDE initial trial to evaluate iStent inject in standalone procedures, Glaukos is also conducting a U.S. IDE pivotal trial to evaluate iStent inject in conjunction with cataract surgery.

Enrollment of approximately 500 subjects in the pivotal combination-cataract trial was completed in mid-2015 and two-year follow-up is set to conclude in mid-2017. Both versions of iStent inject rely on a fluidic method of action that is similar to the company’s flagship iStent® Trabecular Micro-Bypass Stent, which was approved by the FDA in 2012 and has been shown to lower IOP in adult cataract patients with mild-to-moderate open-angle glaucoma.

The iStent inject stents are approximately one-third the size of the first-generation iStent, which Glaukos believes is the smallest medical device ever approved by the FDA.

The iStent inject is already approved for commercial use in the European Union, Australia and Canada. In an international study published recently in Advances in Therapy, 57 phakic open-angle glaucoma eyes underwent standalone iStent inject procedures. At two years postoperative, the iStent inject procedure was shown to reduce unmedicated IOP by 42%, to a mean of 14.2 mm Hg from a preoperative mean of 24.4 mm Hg.

“Glaukos pioneered Micro-Invasive Glaucoma Surgery, or MIGS, to provide new treatment options for glaucoma patients and practitioners,” said Thomas Burns, Glaukos president and chief executive officer. “Completion of enrollment in the initial phase of the standalone iStent inject clinical trial marks achievement of an important milestone in our mission to transform glaucoma therapy.”