Minimally invasive glaucoma surgery (MIGS) is the latest development in the treatment of glaucoma. Two MIGS devices have already been approved for the U.S. market and more are in development. So are a variety of other novel devices that have the potential to transform the treatment of glaucoma.
Seven companies presented their latest devices in development or marketing during a “New Horizons in Glaucoma Devices” session as part of the New Horizons Forum at the 2017 Glaucoma 360 meeting. Malik Y. Kahook, MD, Slater Family Endowed Chair of Ophthalmology, University of Colorado, Denver, and Thomas W. Samuelson, MD, founding partner, Minnesota Eye Consultants, Minneapolis, were the sessions moderators.
The CyPass Micro-Stent was the second MIGS device to win FDA approval after the iStent (Glaukos). Both devices are indicated for the reduction of intraocular pressure (IOP) in adult patients with mild-to-moderate primary, open-angle glaucoma (POAG) in conjunction with cataract surgery.
“This is the first device in the United States designed to vent into the supraciliary space,” said Steven D. Vold, MD, president, Vold Vision, Bentonville, AR, and consultant to Alcon Laboratories. “This is something that can very easily be implemented into practice by comprehensive ophthalmologists. It may lower IOP more than a trabecular bypass. It has superior IOP-lowering efficacy than cataract surgery alone and the safety profile is comparable to cataract surgery alone.”
Complication rates are identical for CyPass plus cataract as in cataract alone, Dr. Vold continued. More than 70% of eyes achieved an unmedicated IOP reduction of at least 20% and many have maintained the reduction for as long as 7.5 years. Of patients who respond, 93% are off all medications at 24 months.
The XEN gel stent also was cleared for marketing in the United States in 2016 and launched in 2017. The 6-mm stent is implanted through the trabeculum into the subconjunctival space via a small incision in the cornea.
The highly flexible stent was approved for refractory POAG in patients who are unresponsive to maximum-tolerated medical therapy. More than 11,000 XEN stents have been placed globally and there were no operative adverse events reported in the trials used for FDA approval.
“These were patients with refractory glaucoma, medicated baselines were 25 mm Hg, mean meds 3.5, visual field deviation -15,” said Michael R. Robinson, MD, vice president, Therapeutic Area Head, Anterior Segment and Consumer Eye Care. “At month 12, mean meds were 1.7, 39% were drug free with a mean IOP of 13.5 mm Hg. This can be very successful in patients who have refractory glaucoma.”
Adverse events are minimal and minor, Dr. Robinson continued. About a quarter of patients required needling. Hypotension was transient and generally disappeared within seven days.