FDA Approves iStent Inject Trabecular Micro-Bypass System For Managing Glaucoma Patients' IOP

The US Food and Drug Administration (FDA) granted premarket approval for the iStent inject Trabecular Micro-Bypass System, which is indicated for the reduction of intraocular pressure (IOP) in adult mild-to-moderate primary open-angle glaucoma patients undergoing concomitant cataract surgery, announced Glaukos Corporation.

The approval is based on the US IDE pivotal study that included 41 investigational sites and 505 mild-to-moderate primary open-angle glaucoma eyes that were randomized to receive iStent inject in addition to undergoing cataract surgery (n=387) or cataract surgery only (n=118).

“US ophthalmic surgeons have been eagerly awaiting the availability of iStent inject, which offers them an exciting new treatment option for effectively managing glaucoma patients’ IOP while potentially reducing or eliminating the need for topical hypotensive medications,” Thomas Samuelson, MD, surgeon, Minnesota Eye Consultants, adjunct professor, University of Minnesota, investigator, iStent inject pivotal trial, said in a statement. “The results of the US trial, along with those of numerous international peer-reviewed studies, confirm that iStent inject provides predictable, clinically significant IOP reductions with an excellent safety profile through an elegant, micro-invasive procedure with minimal tissue disruption.”

Data show that the system achieved a statistically significant reduction in unmedicated diurnal IOP in those undergoing cataract surgery at 24 months as 75.8% of the iStent inject cohort achieved a 20% or greater reduction in unmedicated IOP, while the mean unmedicated IOP reduction was 8 mmHg for the iStent inject cohort.

Aside from meeting the study’s primary and secondary endpoints, at 24 months, the data show that the iStent inject cohort achieved a 31% mean reduction or 7.7 mmHg, in unmedicated IOP from an unmedicated mean baseline IOP of 24.8 mmHg to 17.1 mmHg.

Through 24 months, the overall rate of adverse effects was similar to cataract surgery alone. The reported common postoperative adverse effects include stent obstruction (6.2%), intraocular inflammation (5.7% for iStent inject vs. 4.2% for cataract surgery only), secondary surgical intervention (5.4% vs. 5%) and BCVA loss ≥ 2 lines ≥ 3 months (2.6% vs. 4.2%).

The iStent inject is designed to optimize the natural physiological outflow of aqueous humor by creating 2 patient bypasses through the trabecular meshwork, which results in multi-directional flow through Schlemm’s canal. The device includes 2 heparin-coated titanium stents that are preloaded into an auto-injection system, allowing surgeons to precisely implant stents into 2 trabecular meshwork locations through a single corneal entry point in a straightforward click-and-release motion. Each iStent inject stent is approximately .23 mm x .36 mm, or about one-third the size of the first-generation iStent.

The device is expected to launch commercially in the third quarter.