GlaucomaNCT07143708
Safety and Effectiveness of PreserFlo and XEN Stents With or Without Amniotic Membrane in Glaucoma Surgery
A study testing Glaucoma Surgery with Amniotic Membrane and Glaucoma Surgery without Amniotic Membrane in people with Glaucoma, run by Nova Scotia Health Authority.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Glaucoma
- What is being tested?
- Glaucoma Surgery with Amniotic Membrane and Glaucoma Surgery without Amniotic Membrane
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 156 participants
- Where
- No sites listed yet
- Study dates
- 1 Dec 2025to 31 Dec 2027
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Comparison of the Safety and Efficacy of PreserFlo MicroShunt and XEN Stent Alone Versus With Amniotic Membrane in Glaucoma Surgery
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.
Read more
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.
Read the detailed description
Glaucoma is the leading cause of permanent blindness worldwide. Glaucoma is damage to the optic nerve, which sends information from the eye to the brain. This damage causes vision to weaken. Treatment for glaucoma includes the use of medication drops and, ultimately, surgery. The type of surgery is decided by determining the severity and progress of an individual's vision loss.
Certain glaucoma surgeries (including PreserFlo microshunts, and Xen stents) involve creation of an alternative passage for the liquid inside of the eye to be drained. Glaucoma surgery is complex and excessive inflammation and scarring can increase pressure inside the eye and lead to surgical failure. We hope that covering PreserFlo microshunts and Xen stents with amniotic membrane will result in reduced scarring and better pressure outcomes after these surgeries.
Previous research has shown that amniotic membrane is safe for the eye and has improved the outcomes of other similar glaucoma surgeries. However, there are no studies that have investigated whether amniotic membrane is a safe and effective in PreserFlo microshunts, and Xen stents surgeries.
- Conditions
- Glaucoma
- Being tested
- Glaucoma Surgery with Amniotic Membrane, Glaucoma Surgery without Amniotic Membrane
- Keywords
- Galucoma, Glaucoma Surgery, Stent surgery, MicroShunt surgery
- Medical subject headings
- Glaucoma
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Glaucoma Surgery with Amniotic MembraneOther
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).
Glaucoma Surgery without Amniotic MembraneOther
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).
| Study group | Role | What they receive |
|---|---|---|
| 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. Receives: 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. Receives: Other: Glaucoma Surgery with Amniotic Membrane |
What is being measured
The primary outcome is the main question the study is designed to answer.
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).
Measured: 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
Measured: Baseline to 3, 6, and 12 months
Secondary outcomes (3)
Number of re-operations
To compare the number of re-operations per patient at 12 months between the treatment groups, we will use a negative binomial regression model. The dependent variable will be the total number of re-operations per patient, and the independent variable will be the treatment group. Results will be reported as incidence rate ratios (IRRs) with 95% confidence intervals and p-values.
Measured: Through 12 months post-op
Number of Glaucoma Medications
Count of post-operative glaucoma medication classes required at each visit. Generalized linear mixed model with negative binomial distribution compares groups over time; reported as rate ratios with 95% CIs and p-values.
Measured: 3, 6 and 12 month post-op
Time to Surgical Failure
Failure is defined as any of: (a) IOP >21 mmHg or <20% reduction from baseline on two consecutive visits; (b) IOP ≤5 mmHg on two consecutive visits (hypotony); (c) any re-operation for glaucoma; or (d) loss of light perception vision. Analyzed by Kaplan-Meier and Cox proportional hazards; reported as hazard ratio with 95% CI and p-value.
Measured: From surgery to 12 months post-op (failures assessed after postoperative Month 3)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Aug 2025
- Study start1 Dec 2025 (estimated)
- Primary completion31 Dec 2027 (estimated)
- Study completion31 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for GlaucomaStudies of the same condition, open and under way.
- More trials run by Nova Scotia Health AuthorityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 156 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Nova Scotia Health Authority
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Lesya Shuba, Nova Scotia Health Authority
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07143708
- Sponsor's protocol ID
- 1031327
- Status last verified
- Aug 2025
- First submitted
- 20 Aug 2025
- Last updated
- 27 Aug 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 27 Aug 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Safety and Efficacy of PreserFlo MicroShunt and XEN Stent Alone Versus With Amniotic Membrane in Glaucoma Surgery
- ClinicalTrials.gov ID
- NCT07143708
- Acronym / sponsor ID
- 1031327
- Conditions
- Glaucoma
- Keywords
- Galucoma, Glaucoma Surgery, Stent surgery, MicroShunt surgery
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 156 participants (estimated)
- Lead sponsor
- Nova Scotia Health AuthorityUniversity, hospital or other
- Study start
- 1 Dec 2025 (estimated)
- Primary completion
- 31 Dec 2027 (estimated)
- Study completion
- 31 Dec 2027 (estimated)
- First posted
- 27 Aug 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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.
Detailed description
Glaucoma is the leading cause of permanent blindness worldwide. Glaucoma is damage to the optic nerve, which sends information from the eye to the brain. This damage causes vision to weaken. Treatment for glaucoma includes the use of medication drops and, ultimately, surgery. The type of surgery is decided by determining the severity and progress of an individual's vision loss.
Certain glaucoma surgeries (including PreserFlo microshunts, and Xen stents) involve creation of an alternative passage for the liquid inside of the eye to be drained. Glaucoma surgery is complex and excessive inflammation and scarring can increase pressure inside the eye and lead to surgical failure. We hope that covering PreserFlo microshunts and Xen stents with amniotic membrane will result in reduced scarring and better pressure outcomes after these surgeries.
Previous research has shown that amniotic membrane is safe for the eye and has improved the outcomes of other similar glaucoma surgeries. However, there are no studies that have investigated whether amniotic membrane is a safe and effective in PreserFlo microshunts, and Xen stents surgeries.
Study design
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| No Amniotic Membrane Group | Active comparator | Other: Glaucoma Surgery without Amniotic MembranePatients 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. |
| Amniotic Membrane Group | Experimental | Other: Glaucoma Surgery with Amniotic MembranePatients 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. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (3 listed)
- 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
Key exclusion criteria (8 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Glaucoma Surgery with Amniotic MembraneArm 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). | Other | Amniotic Membrane Group |
| Glaucoma Surgery without Amniotic MembraneArm 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). | Other | No Amniotic Membrane Group |
Primary outcome
Rate of adverse events
Time frame: Surgery (Day 0) to 12 months
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).
Relative Reduction in Intraocular Pressure (IOP) at 3, 6, and 12 Months
Time frame: Baseline to 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
3 secondary outcomes
Number of re-operations
Time frame: Through 12 months post-op
Number of Glaucoma Medications
Time frame: 3, 6 and 12 month post-op
Time to Surgical Failure
Time frame: From surgery to 12 months post-op (failures assessed after postoperative Month 3)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 27 Aug 2025.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Questions about this trial
What is this clinical trial studying?
A study testing Glaucoma Surgery with Amniotic Membrane and Glaucoma Surgery without Amniotic Membrane in people with Glaucoma, run by Nova Scotia Health Authority.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 27 Aug 2025. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Lesya Shuba, MD (1-902-473-3410, LSHUBA@DAL.CA), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Rate of adverse events (time frame: Surgery (Day 0) to 12 months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 27 Aug 2025.