Supraciliary Microstent in Refractory Open-Angle Glaucoma: Two-Year Outcomes from the DUETTE Trial

The aim of the study was to report longer term (24-month) outcomes for primary open-angle glaucoma (POAG) patients refractory to medical therapy implanted with a supraciliary microstent (CyPass Micro-Stent, Alcon) in the DUETTE clinical study.

Sixty-five eyes were enrolled in this multicenter single-arm trial. Enrolled patients had POAG and intraocular pressure (IOP) >21 mmHg at baseline on 1-4 ocular hypotensive medications. Microstent implantation was performed as stand-alone surgery in these phakic or pseudophakic patients through a standard clear corneal approach. IOP and the use of IOP-lowering medications were monitored in this 1-year extension beyond the 12-month primary endpoint.

Two-year follow-up visits were scheduled to confirm the 12-month results; safety data were obtained for 37 eyes of 35 patients. IOP at the end of the 24-month follow-up was 16.8 mmHg (n = 32), with a mean reduction of 7.7 mmHg from the baseline IOP of 24.5 mmHg (n = 65). Medication use was decreased from an average of 2.1 (baseline) to 1.5 at 24 months. The IOP and medication use at 24 months were consistent with the 12-month results (16.4 mmHg, 1.4 medications) reported previously. The adverse event profile remained as described for the first 12 months postimplantation.

Placement of a supraciliary microstent provides up to 24 months of effective IOP lowering for medication-refractory POAG patients while, on average, decreasing the requirement for ocular hypotensive medications.