DUETTE microstent shows good IOP control

Ophthalmology Times reported on May 23 that the DUETTE trial found a glaucoma microstent produced intraocular pressure control when used as a stand-alone procedure in patients with open-angle glaucoma. The device discussed in the report was the CyPass Micro-Stent, which Quang H. Nguyen, MD, described as appearing safe for patients seeking to reduce reliance on multiple glaucoma medications. The article said the DUETTE study enrolled patients whose disease remained uncontrolled on medication and who were already being considered for trabeculectomy. The report also said the device was investigational in the United States at the time described. ### Which device and trial were described? The Ophthalmology Times report identified the device as the CyPass Micro-Stent, developed by Transcend Medical, and said Nguyen discussed results from the DUETTE trial. The stent is implanted into the supraciliary space through a small corneal incision, according to the report. The DUETTE trial, as described by Ophthalmology Times, was a multicenter study of 65 patients with open-angle glaucoma who were refractory to medications and received the device as a stand-alone procedure. (ophthalmologytimes.com) The trial was conducted at eight sites in four European countries. ### Who was included in DUETTE? The report said DUETTE enrolled patients with grade III or IV open-angle glaucoma and a medicated intraocular pressure between 21 and 35 mm Hg while using one to four glaucoma medications. (ophthalmologytimes.com) Patients could be either phakic or pseudophakic. At enrollment, the average patient age was 68 years and mean baseline intraocular pressure was 24.5 mm Hg, according to Ophthalmology Times. (ophthalmologytimes.com) The mean number of baseline medications was 2.2, and 37% of patients were using three or more medications. The report said 63% of patients were phakic. ### What safety findings were reported? Ophthalmology Times said no sight-threatening complications or serious adverse events occurred in the DUETTE cohort. (ophthalmologytimes.com) Nguyen was quoted as saying, “Seven patients had an IOP spike that resolved.” The same report said smaller numbers of patients experienced transient hyphema, cataract progression, peripheral anterior synechiae, or a best-corrected visual acuity loss of two lines or greater. (ophthalmologytimes.com) The outcome measures listed for the study were adverse events, mean intraocular pressure, and intraocular-pressure lowering at 12 months. ### How does DUETTE fit with other data mentioned in the report? (ophthalmologytimes.com) Nguyen also referenced the COMPASS study, which Ophthalmology Times described as the largest MIGS trial to date, with 505 patients and two years of follow-up. The report said COMPASS had been statistically significantly positive across all endpoints at both one and two years, according to Nguyen. A separate Europe PMC entry for a later publication described DUETTE as a multicenter single-arm trial in 65 eyes evaluating a supraciliary microstent in refractory primary open-angle glaucoma, indicating the study later generated longer-term follow-up in the literature. (ophthalmologytimes.com) ### Why was stand-alone use notable in this report? The Ophthalmology Times article described the microstent as being used without cataract surgery, which distinguishes DUETTE from many MIGS studies that evaluate devices in combination procedures. (ophthalmologytimes.com) Nguyen said MIGS devices are important because of their ab interno approach, minimal tissue damage, and lower complication profile compared with traditional surgery. That characterization was Nguyen’s assessment in the report. (europepmc.org) The report said DUETTE patients were already under consideration for trabeculectomy when they entered the study, placing the device in a treatment setting where surgeons were weighing a less invasive option against conventional filtration surgery. Ophthalmology Times said the reported DUETTE outcomes were measured at 12 months. (ophthalmologytimes.com)