Performance and Safety of a New Ab Interno Gelatin Stent in Refractory Glaucoma at 12 Months

Abstract

Purpose: To evaluate the intraocular pressure (IOP)-lowering performance and safety of an ab interno gelatin stent (XEN 45 Gel Stent, Allergan plc, Irvine, California, USA), a minimally invasive glaucoma surgery device, in refractory glaucoma.

Design: Single-arm, open-label, multicenter clinical study.

Methods: Following mitomycin C pretreatment, the stent was placed ab interno in patients who failed prior filtering/cilioablative procedure or had uncontrolled IOP on maximum-tolerated medical therapy, with medicated IOP ≥20 and ≤35 mm Hg and visual field mean deviation ≤-3 dB. Primary performance outcomes: patients (%) achieving ≥20% IOP reduction from baseline on the same or fewer medications and mean IOP change from baseline at month 12. Procedure-related complications and ocular adverse events (AEs) were assessed.

Results: Sixty-five patients were implanted (intent-to-treat/safety population). At 12 months, 75.4% (46/61; observed data) reported ≥20% IOP lowering from baseline on the same or fewer medications. Mean IOP change from baseline was -9.1 mm Hg (95% confidence interval [CI]: -10.7, -7.5) (n = 52; observed data) at 12 months, excluding patients with missing data (n = 4) and those requiring a glaucoma-related secondary surgical intervention (n = 9). Mean medication count decreased from 3.5 (baseline) to 1.7 (12 months). No intraoperative complications or unexpected postoperative AEs were reported. Most AEs were mild/moderate; common AEs included needling (without sight-threatening complications), nonpersistent loss of best-corrected visual acuity, and transient hypotony (requiring no surgical intervention).

Conclusions: The gelatin stent reduced IOP and medication use without raising unexpected safety concerns, offering a minimally invasive surgical option for refractory glaucoma patients.