Safety and Effectiveness of PreserFlo and XEN Stents With or Without Amniotic Membrane in Glaucoma Surgery

NCT07143708 | Not Yet Recruiting

• 1 other identifier: 1031327
• Study Type: interventional
• Target: 156
• Locations: 0 countries
• Sites: N/A

Brief Summary

Glaucoma is one of the leading causes of permanent blindness in the world. It happens when the optic nerve-the connection between the eye and the brain-is damaged. As this damage gets worse, vision is slowly lost. Glaucoma treatments often begin with eye drops to lower eye pressure. If drops are not enough, surgery may be needed. The type of surgery depends on how advanced the glaucoma is and how much vision has already been lost. Some glaucoma surgeries, including trabeculectomy, PreserFlo MicroShunt, and XEN Stent, create a new pathway for fluid to drain out of the eye. This helps lower pressure inside the eye. However, after surgery, the body's natural healing process can sometimes cause inflammation and scarring, which may block the new drainage pathway. If this happens, eye pressure can rise again, and the surgery may not work as well as hoped. This study is testing whether covering the PreserFlo or XEN devices with amniotic membrane (a safe tissue already used in other eye surgeries) can reduce scarring, improve healing, and lead to better long-term results. Amniotic membrane has already been used safely in many types of eye surgeries. It has been shown to improve healing and reduce scarring in some glaucoma surgeries. But it has not yet been studied in PreserFlo MicroShunt or XEN Stent procedures. The goal is to see if adding amniotic membrane makes the surgery safer and more effective for people with glaucoma.

Conditions

Glaucoma

Keywords

Galucoma; Glaucoma Surgery; Stent surgery; MicroShunt surgery

Outcome Measures

Primary Outcomes (2)

• Rate of adverse events

  Proportion of study eyes with ≥1 of: persistent uveitis, blebitis, endophthalmitis, clinically significant hypotony, stent erosion, bleb dysesthesia, or loss of best-corrected visual acuity. Each AE recorded as yes/no; between-group comparisons via logistic regression (adjusting for device type and baseline IOP).

  Surgery (Day 0) to 12 months

• Relative Reduction in Intraocular Pressure (IOP) at 3, 6, and 12 Months

  Percent change from baseline IOP at each post-operative visit. Calculated per study eye as: \[(Baseline IOP - Visit IOP) / Baseline IOP\] × 100. Primary efficacy analysis uses a linear mixed-effects model (repeated measures) with fixed effects for treatment group (amniotic membrane vs no membrane), visit (3/6/12 months), treatment × visit interaction, device type (PreserFlo vs XEN), and baseline IOP; participant (study eye) included as a random effect. Estimates will report least-squares mean differences between groups in percent reduction at each visit and an overall treatment effect across visits, with 95% confidence intervals and p-values

  Baseline to 3, 6, and 12 months

Secondary Outcomes (3)

• Number of re-operations

  Through 12 months post-op

• Number of Glaucoma Medications

  3, 6 and 12 month post-op

• Time to Surgical Failure

  From surgery to 12 months post-op (failures assessed after postoperative Month 3)

Study Arms (2)

No Amniotic Membrane Group

ACTIVE COMPARATOR

Patients receive standard glaucoma surgery (PreserFlo MicroShunt or XEN Stent) without additional covering. The choice between PreserFlo or XEN is not part of the study design-it's determined beforehand by the surgeon as part of regular care.

Other: Glaucoma Surgery without Amniotic Membrane

Amniotic Membrane Group

EXPERIMENTAL

Patients receive standard glaucoma surgery (PreserFlo MicroShunt or XEN Stent) with additional covering. The implanted MicroShunt or Stent is covered with an amniotic membrane patch. The choice between PreserFlo or XEN is not part of the study design-it's determined beforehand by the surgeon as part of regular care.

Other: Glaucoma Surgery with Amniotic Membrane

Interventions

Glaucoma Surgery with Amniotic Membrane OTHER

Arm 2: Glaucoma Surgery with Amniotic Membrane Participants undergo glaucoma surgery with either a PreserFlo MicroShunt or a XEN Stent, as determined by the treating surgeon. In this group, the implanted stent is covered with an amniotic membrane patch to reduce postoperative scarring and improve long-term outcomes. Follow-up visits are scheduled as per standard of care for glaucoma surgery (up to 12 months).

Amniotic Membrane Group

Glaucoma Surgery without Amniotic Membrane OTHER

Arm 1: Glaucoma Surgery without Amniotic Membrane Participants undergo glaucoma surgery with either a PreserFlo MicroShunt or a XEN Stent, as determined by the treating surgeon. No modifications are made to the procedure. Follow-up visits are scheduled as per standard of care for glaucoma surgery (up to 12 months).

No Amniotic Membrane Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 years and older
• Patients selected for PreserFlo microshunt surgery and XEN stent alone or in combination with cataract surgery.
• Ability to comprehend the study procedures

You may not qualify if:

• Unwilling or unable to give consent
• Unable to come for scheduled post-operative visits
• Pregnant or nursing women
• Previous cyclodestructive procedures, scleral buckling procedures, or presence of silicone oil
• Conjunctival scarring precluding a glaucoma surgery superiorly
• Active iris neovascularization or active proliferative retinopathy
• Vitreous in the anterior chamber for which a vitrectomy is anticipated.
• Previous trabeculectomy, tube-shunt implantation, or surgeries that shunt aqueous outflow into the subconjunctival space

Sponsors & Collaborators

• Nova Scotia Health Authority: lead

MeSH Terms

Conditions

Glaucoma

Condition Hierarchy (Ancestors)

Ocular Hypertension; Eye Diseases

Central Study Contacts

Lesya Shuba, MD

CONTACT

1-902-473-3410; LSHUBA@DAL.CA

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: August 20, 2025
• First Posted: August 27, 2025
• Study Start: December 1, 2025
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: August 27, 2025

Record last verified: 2025-08