A 3-Year Post-Marketing Surveillance Study of EX-PRESS™ Glaucoma Filtration Device in Japanese Eyes

A post-marketing surveillance study of EX-PRESS™ Glaucoma Filtration Device was conducted to confirm the safety and efficacy of the product in clinical settings.

Patients with glaucoma with insufficient intraocular pressure (IOP) reduction despite glaucoma medication, laser therapy or prior glaucoma surgery underwent EX-PRESS™ filtration surgery and were followed for 3 years.

The study was conducted from July 2012 to December 2017 and included 890 eyes of 835 patients from 52 medical institutions across Japan. The efficacy analysis of 821 eyes showed that the mean ± SD IOP changed from 25.0 ± 9.1 mmHg at baseline to postoperative 14.0 ± 5.4, 14.2 ± 5.8, and 14.5 ± 5.8 mmHg at 12, 24, and 36 months, respectively. The mean ± SD number of glaucoma medications used reduced from 3.5 ± 1.4 at baseline to postoperative 1.0 ± 1.5, 1.4 ± 1.7, and 1.7 ± 1.7 at 12, 24, and 36 months, respectively. The survival analysis showed that the rate of success, defined as IOP ≤ 21 mmHg and a percent reduction of ≥ 20% with or without glaucoma medication, was 64.6% at 3 years postoperatively. In the safety analysis of 824 eyes, the incidence of malfunctions was 31.9% and the incidence of adverse events (AEs) for which a causal relationship could not be ruled out was 22.2%. There were no reports of infection. The most common malfunctions were device-iris touch (26.9%), device malfunction (2.9%), device-cornea touch (2.7%), and device obstruction (1.7%). The most common AEs were IOP increased (11.9%), corneal endothelial cell loss (5.7%), glaucoma filtration surgery (5.0%), device removal (5.0%), hypotony (3.2%), and bleb reconstruction (2.4%). Five cases of reduced visual acuity and one case of visual field defect aggravation were reported as adverse events related to vision. The mean endothelial cell density (ECD) decreased after surgery but remained above 2000 cells/mm² at 36 months postoperatively. Percent change of ECD at 36 months from baseline was - 8.2 ± 22.5%.

The current study confirmed the efficacy and safety of the EX-PRESS™ Glaucoma Filtration Device.