MIGS: the Next Generation
The role of microinvasive glaucoma surgery (MIGS) continues to expand. Revenue from the iStent Trabecular Micro-Bypass Stent (Glaukos) was approximately $21 million in 2013, and analysts predict it will reach approximately $70 million in 2015. The device is becoming a growing number of ophthalmologists’ first choice for glaucoma therapy when patients have both primary open-angle glaucoma and cataract. The Trabectome (NeoMedix) remains a viable trabecular bypass procedure as well.
Growth of the MIGS space has been amazingly rapid. Canaloplasty has evolved from predominantly an external approach to an ab interno technique. In addition, both viscocanalostomy and an ab interno trabeculotomy are now being performed with new instrumentation that allows for 360º viscodilation and removal of the internal wall of Schlemm canal (Visco360 and Trab360, respectively; Sight Sciences). Another new option is use of the Kahook Dual Blade (New World Medical) for an ab interno trabeculotomy.
Glaukos recently reported that enrollment is complete in the pivotal FDA clinical trial of iStent Inject technology. Enrollment is also complete in the Hydrus IV pivotal trial. The Hydrus (Ivantis) is a nitinol trabecular bypass device that stents open approximately 3 clock hours of Schlemm canal. The hope is that both technologies will offer greater efficacy than the first-generation iStent without decreasing safety.
Transcend Medical announced completion of the Compass pivotal trial evaluating the CyPass Micro-Stent, and it is hoped that the device will be available on the US market in 2016 or 2017. The ab interno suprachoroidal device has demonstrated promising safety and efficacy for the management of patients with primary open-angle glaucoma in the setting of cataract surgery. A US investigational device exemption trial of another suprachoroidal device, the iStent Supra (Glaukos), is underway.
Big news in the MIGS space was the recent announcement that Allergan will acquire AqueSys, the manufacturer of the Xen45. The US investigational device exemption trial of this ab interno subconjunctival implant is fully enrolled, and Allergan expects final FDA approval of the technology via the 510(k) device pathway in 2016 or early 2017. InnFocus, meanwhile, has an ab interno approach in its pipeline.
Although MIGS is in its formative years and the exact role of these procedures in the glaucoma treatment paradigm has yet to be defined, surgeons’ excitement about the technologies grows with each passing year. The adventure is just beginning! n
Steven D. Vold, MD
Chief Medical Editor