Background: This was a prospective, randomized, double-masked, multicenter, 24-month study to compare effectiveness and safety outcomes following standalone implantation of two types of current generation trabecular stents in adults with open-angle glaucoma (OAG). An interim analysis was performed at month 6.

Methods: Eyes with OAG, mean IOP ≤ 24 mmHg on zero to three intraocular pressure (IOP)-lowering medications at screening, and with baseline mean diurnal IOP (MDIOP) 21-36 mmHg after medication washout were randomized to standalone implantation of the current generation of three trabecular micro-bypass stents (iStent infinite) or one trabecular bypass stent (Hydrus). Eyes on medication were to undergo a medication washout prior to the month 6 visit. Analyses included a comparison of the proportion of iStent infinite versus Hydrus eyes achieving MDIOP reduction of 20% or greater from baseline at month 6. Reduction from baseline in MDIOP and number of medications were also assessed. Safety parameters included intraoperative/postoperative complications, corrected visual acuity, slit-lamp biomicroscopy, ophthalmoscopy, gonioscopy, perimetry, and adverse events.

Results: Eyes with primarily mild-to-moderate disease severity were randomized: 91 iStent infinite eyes had screening mean (± standard deviation [SD]) IOP of 17.0 ± 3.2 mmHg on 1.6 ± 0.9 medications and baseline unmedicated MDIOP of 23.7 ± 2.9 mmHg; 89 Hydrus eyes had screening mean (± SD) IOP of 17.1 ± 3.3 mmHg on 1.5 ± 0.9 medications and baseline unmedicated MDIOP of 23.5 ± 2.7 mmHg. At month 6, a similar proportion of iStent infinite eyes (82.7%) versus Hydrus eyes (78.9%) achieved MDIOP reduction ≥ 20% from baseline regardless of IOP medication use or surgical complications. The difference was statistically significantly different (78.2% iStent infinite versus 65.0% Hydrus) for unmedicated MDIOP reduction ≥ 20% from baseline in eyes with no surgical complications (difference 13.2%; 95% confidence interval (CI) 3.0%, 23.3%). Mean MDIOP change from baseline, regardless of IOP medication use or surgical complications, was similar between groups (- 7.4 ± 2.9 mmHg iStent infinite and - 7.2 ± 2.9 mmHg Hydrus), whereas unmedicated MDIOP change from baseline without surgical complications was statistically significantly superior in iStent infinite eyes (- 6.8 ± 4.1 mmHg) versus Hydrus eyes (- 5.7 ± 4.1 mmHg) (difference - 1.1 mmHg; 95% CI - 2.0 mmHg, - 0.2 mmHg). Improper stent placement was reported in one iStent infinite and seven Hydrus eyes (1.1% versus 7.9%). One iStent infinite versus four Hydrus eyes experienced peripheral anterior synechiae > 1 mm (1.1% versus 4.5%). Overall, there were significantly fewer surgical complications in the iStent infinite eyes (3.3%) compared to Hydrus eyes (16.9%; difference of - 13.6%, 95% CI - 23.8%, - 3.4%).

Conclusions: In this study of standalone implantation of current trabecular stent technologies in subjects with OAG, high proportions in both groups achieved clinically meaningful IOP reduction. When considering surgical complications as failures, a statistically significantly greater proportion of iStent infinite eyes versus Hydrus eyes had no surgical complications and achieved an unmedicated MDIOP reduction of ≥ 20%. The iStent infinite group also had clinically relevant and statistically significantly superior reduction from baseline in unmedicated MDIOP without surgical complications compared to Hydrus. Background: ClinicalTrials.gov identifier, NCT05127551.