Microstent implantation had favorable and safe results in a group of patients with open-angle glaucoma in the DUETTE trial.
Take-home message: Microstent implantation had favorable and safe results in a group of patients with open-angle glaucoma in the DUETTE trial.
By Vanessa Caceres; Reviewed by Quang H. Nguyen, MD
La Jolla, CA-A certain glaucoma micro-stent (CyPass Micro-Stent, Transcend Medical) appears safe for patients looking to reduce reliance on multiple glaucoma medications, and for lowering IOP, said Quang H. Nguyen, MD.
Microinvasive glaucoma surgery (MIGS) devices, such as this implant, are important for glaucoma patients and surgeons because of their ab interno approach, minimal damage to tissue, superior safety, and low complication profile compared with traditional surgery, said Dr. Nguyen, associate head, Division of Ophthalmology, and director, Glaucoma Service, Cataract and Anterior Segment, Scripps Health Clinic, La Jolla, CA.
Although various trials are under way for the device, Dr. Nguyen spoke about the DUETTE trial. The implant is an investigational device in the United States.
Other trials have included or are including the device, such as the COMPASS study in the United States, which, Dr. Nguyen said, is the largest MIGS trial to date. The COMPASS study includes 505 patients for 2 years of follow up. Results with the COMPASS trial have been statistically significantly positive across all endpoints at both 1 and 2 years, he noted.
The DUETTE trial included 65 open-angle glaucoma patients refractory to medications receiving the device as a stand-alone procedure. The trial took place at eight sites in four European countries. The mean outcomes were adverse events, mean IOP, and IOP lowering at 12 months.
Patients included in the trial had grade III or IV open-angle glaucoma and a medicated IOP between 21 and 35 mm Hg with the use of one to four glaucoma medications. Patients could be phakic or pseudophakic. At the time of enrollment, the included patients were under consideration for a trabeculectomy.
The device is surgically implanted into the supraciliary space of the eye through a small corneal incision, Dr. Nguyen explained.
The average patient age was 68, and the mean baseline was 24.5 mm Hg. Although the mean number of baseline medications was 2.2, 37% of those included in the trial used three or more medications. Sixty-three percent of patients were phakic.
Regarding patient safety, no sight-threatening complications or serious adverse events occurred.
“Seven patients had an IOP spike that resolved,” Dr. Nguyen said.
There were smaller numbers of patients that experienced transient hyphema, cataract progression, peripheral anterior synechiae, or a best-corrected visual acuity loss of two lines or greater. Seventeen percent of patients went on to require a trabeculectomy; 6% exited the study by choice, and 4.6% were lost to follow up.
There was a 30% decrease in mean IOP from baseline (24.5 mm Hg) to 6 months (17.7 mm Hg) to 1 year (16.7 mm Hg), Dr. Nguyen said, adding that the 1-year number reflects a total of 47 patients versus the 65 from baseline.
The mean number of medications needed dropped from 2.2 to 1.3 at 6 months and 1.5 at 1 year.
“With 1 year of data, using the CyPass as a stand-alone procedure shows good IOP control with less medication burden,” Dr. Nguyen said. “It’s relatively safe, and it’s very easy to implant. There is a quick learning curve, and it can offer good IOP reduction as a stand-alone procedure,” Dr. Nguyen concluded.
Quang H. Nguyen, MD
This article was adapted from Dr. Nguyen’s presentation during the 2014 meeting of the American Academy of Ophthalmology. Dr. Nguyen and co-researchers are investigators for Transcend Medical.