Comparing two eye implants for lowering eye pressure in open-angle glaucoma
Compares two small eye implants in adults with open-angle glaucoma needing surgery.
Plain-language title generated from the registry record
Registry title: Comparing XEN®-63 Gel Stent and PRESERFLO® MicroShunt
Key facts
- Where
- Lisbon, PortugalSee the site
Where in Portugal
- ULS Santa MariaLisbon, PortugalNot yet recruiting
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Trial details
- Who runs it
- Universitaire Ziekenhuizen KU Leuven
- Trial code
- NCT07359547
- Record updated
- 29 April 2026
- Original description
The goal of this randomized controlled clinical trial is to learn whether two minimally invasive bleb-forming glaucoma implants can effectively treat adult patients with open-angle glaucoma who require surgical lowering of intraocular pressure (IOP). Specifically, the study evaluates whether the PRESERFLO™ MicroShunt is at least as effective as the XEN®-63 Gel Stent in reducing IOP after surgery. Read full original descriptionShow less
Minimally Invasive Bleb-Forming Surgical Approaches for Treating Primary Open-Angle Glaucoma: A Randomized Controlled Trial Comparing XEN®-63 Gel Stent and PRESERFLO® MicroShunt
The goal of this randomized controlled clinical trial is to learn whether two minimally invasive bleb-forming glaucoma implants can effectively treat adult patients with open-angle glaucoma who require surgical lowering of intraocular pressure (IOP). Specifically, the study evaluates whether the PRESERFLO™ MicroShunt is at least as effective as the XEN®-63 Gel Stent in reducing IOP after surgery. 
The main questions it aims to answer are:
* Does the PRESERFLO™ MicroShunt provide IOP reduction at 12 months that is non-inferior to the XEN®-63 Gel Stent? * How do the two devices compare over 24 months with respect to medication reduction, need for additional glaucoma procedures, complications, and preservation of visual function and ocular structures?
Participants will:
* Be randomly assigned (1:1) to receive either the XEN®-63 Gel Stent or the PRESERFLO™ MicroShunt during a single glaucoma surgery. * Attend scheduled follow-up visits over 24 months for eye-pressure measurements, vision testing, visual-field testing, OCT imaging, endothelial-cell counts, and safety assessments. * Receive standard postoperative care and report any complications or additional treatments during the study period.
Inclusion: >40 years of age; An established diagnosis of: Primary open angle glaucoma, Normal tension glaucoma, Pigment dispersion glaucoma (PDG) or Pseudoexfoliative glaucoma (PEX); Inadequately controlled on maximum tolerated medical therapy; Mean Deviation (MD) </= -3; Intraocular pressure of 14-28 mmHg; Endothelial Cell Count ≥1000 cells/mm2.
Exclusion: Previous procedures: Glaucoma shunt/valve/ surgery or cyclodestructive procedure, Selective laser trabeculoplasty within the past 3 months, Incisional ophthalmic surgery involving the conjunctiva within the past 3 months, Clear corneal cataract or trabecular meshwork surgery conducted within the past 6 months; Current corticosteroid use (ocular or oral); Active iris neovascularization or neovascularization of the iris within 6 months of the surgical date; An established diagnosis of: Closed-angle glaucoma or Secondary open-angle glaucoma (besides PDG and PEX); Lens status: Aphakic patients or Anterior chamber intraocular lens; Presence of intraocular silicone oil; No light perception vision; Conjunctival pathologies (e.g., pterygium); Active inflammation (e.g., blepharitis, conjunctivitis, keratitis, uveitis); Vitreous present in the anterior chamber; Unwillingness or inability to give consent, accept randomization or return for and participate in scheduled protocol visits.