Ahmed Valve Glaucoma Implant With Adjunctive Subconjunctival Bevacizumab in Refractory Glaucoma

Study Overview
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Brief Summary
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The investigators aim to demonstrate the efficacy and safety of subconjunctival injection of Avastin as an adjunctive therapy for Ahmed valve glaucoma implant in patients with refractory glaucoma.

Detailed Description
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Several studies have revealed evidences on the substantial role of Vascular endothelial growth factor-A (VEGF-A) in enhancing neovascularization processes. Some studies have shown the efficacy of intravitreal Avastin in reducing level of VEGF-A to improve NVG. On the other hand, recent pathological studies demonstrated that neutralization of VEGF reduced vascularity and decreased scar formation during wound healing, showing that VEGF strongly influence scar tissue formation. This may reduce the formation of encapsulated cyst after glaucoma surgeries and thus might improve the surgical success rate. The effect of subconjunctival bevacizumab as an adjunctive therapy in filtering glaucoma surgeries has been recently illustrated. We aim to demonstrate the efficacy and safety of subconjunctival injection of Avastin as an adjunctive therapy for Ahmed valve glaucoma implant in patients with refractory glaucoma.

Official Title
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Ahmed Valve Glaucoma Implant With Adjunctive Subconjunctival Bevacizumab in Refractory Glaucoma: a Randomized Controlled Clinical Trial

Conditions
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Refractory Glaucoma

Intervention / Treatment
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* Drug: Subconjunctival Avastin
* Device: Ahmed Valve implant


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of refractory glaucoma defined as uncontrolled IOP (> 21 mm Hg) despite maximal antiglaucoma medication, previously failed surgical treatment, or a combination thereof Exclusion Criteria: No light perception elevated IOP associated with silicone oil previous glaucoma drainage device implantation in the same eye previous cyclodestructive treatment increased risk of endophthalmitis (e.g., active adnexal and ocular surface infection, immunosuppression, or immunodeficiency, including the use of systemic steroids) posterior segment disorders, or pre-existing ocular comorbidities (e.g., pterygium, phacodonesis, corneal opacity, or corneal endothelial dystrophies). Only 1 eye per patient was included in this trial.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: ISA+AVI<br>injection of intraoperative subconjunctival Avastin as an adjunct to Ahmed valve implant | Drug: Subconjunctival Avastin<br>* Intraoperative Subconjunctival Avastin 1.25mg; single dose as an adjunct to 184 mm2 surface area Ahmed Glaucoma Valve (AGV Model FP7; New World Medical Inc., Rancho Cucamonga, California, USA)<br>|
| Active Comparator: AVI<br>Ahmed valve implant | Device: Ahmed Valve implant<br>* 184 mm2 surface area Ahmed Glaucoma Valve (AGV Model FP7; New World Medical Inc., Rancho Cucamonga, California, USA)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in intraocular pressure (IOP) | To demonstrate the efficacy and safety of subconjuctival injection of Avastin as an adjunctive therapy for Ahmed valve glaucoma implant in patients with refractory glaucoma. | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surgical failure |  | 12 months | 
| Change in intraocular pressure |  | day 1, week 1, and months 1, 3, 6, 9 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Ahmed valve, Neovascular Glaucoma, Uveitic glaucoma, Failed glaucoma, VEGF-A, Intraocular pressure, Subconjunctival Avastin