The Asia Primary Tube Versus Trab (TVT) Study

Study Overview
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Brief Summary
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Comparison of Ahmed Glaucoma Implant (AGI) against trabeculectomy with mitomycin C in patients with uncontrolled open angle glaucoma

Detailed Description
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The objective of the Asia Primary Tube versus Trab (TVT) study is to compare the efficacy and safety of placement of an Ahmed Glaucoma Implant (AGI) (New World Medical Inc., Rancho Cucamonga, CA, USA) against trabeculectomy with mitomycin C in patients with uncontrolled glaucoma, who may or may not have had previous clear corneal cataract surgery with intraocular lens implantation, over 5 years. Outcome discrimination between the two treatment groups will be made using following parameters: Intraocular pressure Need for supplemental medical therapy Incidence of short and long term surgical complications and need for re-operation. Visual function (Visual acuity and Visual field) Hypothesis: Glaucoma drainage implants have better surgical outcomes in terms of IOP lowering efficacy compared to trabeculectomy with mitomycin-C over 5 years in Asian patients with medically uncontrolled glaucoma.

Official Title
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The Asia Primary Tube Versus Trab (TVT) Study

Conditions
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Glaucoma

Intervention / Treatment
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* Device: Ahmed Glaucoma Implant
* Procedure: Trabeculectomy with Mitomycin C


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Open angle glaucoma including primary open angle glaucoma, pseudoexfoliative or pigmentary glaucoma. IOP > 18 mm Hg on 2 or more medications on at least 2 visits Informed consent given and consent form signed. Exclusion Criteria: Unwilling or unable to give consent, unwilling to accept randomisation, or unable to return for scheduled protocol visits. Pregnant or nursing women No light perception vision Previous incisional intraocular surgery, other than uncomplicated clear corneal cataract surgery Previous ocular laser in study eye (keratorefractive surgery and cyclodestructive procedure), except for laser trabeculoplasty procedures (Argon Laser and Selective Laser Trabeculoplasty) Iris neovascularisation or proliferative retinopathy Primary angle closure or primary angle closure glaucoma Iridocorneal endothelial syndrome or anterior segment dysgenesis Epithelial or fibrous downgrowth Aphakia Chronic or recurrent uveitis Severe posterior blepharitis Unwilling to discontinue contact lens use after surgery Glaucoma secondary to penetrating keratoplasty, trauma, steroids, retinal disease/surgery or neovascular disease Conjunctival scarring from prior ocular surgery, trauma or cicatrizing disease precluding a superior trabeculectomy Need for glaucoma surgery combined with other ocular procedures (i.e. cataract surgery, penetrating keratoplasty, or retinal surgery) or anticipated need for urgent additional ocular surgery Advanced glaucoma with MD <-20dB

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tube implant<br>Ahmed Glaucoma Implant (AGI) surgery | Device: Ahmed Glaucoma Implant<br>* Conjunctival Flap Scleral Exposure Insertion of Episcleral Plate Priming of the tube prior to AC entrance Insertion of Tube into the Anterior Chamber Suturing tube Coverage of tube<br>|
| Active Comparator: Trabeculectomy<br>Trabeculectomy with mitomycin C surgery | Procedure: Trabeculectomy with Mitomycin C<br>* Conjunctival Flap Mitomycin C Application Scleral Flap Paracentesis Excision of Limbal Tissue Peripheral Iridectomy Scleral Flap Closure Conjunctival Flap Closure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Failure | Failure defined by ANY of the following criteria: IOP ≥ 18 mm Hg on two consecutive follow-up visits after 6 months IOP not reduced to 20% below baseline on two consecutive visits after 6 months IOP ≤ 5 mm Hg with visually significant hypotony maculopathy on two consecutive visits after 3 months Additional glaucoma surgery, excluding laser suture lysis, removal of releasable trabeculectomy or conjunctival sutures, needling of the bleb or tube plate with or without 5FU, subconjunctival 5FU injections and anterior chamber reformation. Loss of light perception vision | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| IOP | Intraocular pressure (mmHg) | 60 months | 
| Best Corrected Visual Acuity (BCVA) | ETDRS visual acuity chart (logMAR or equivalent) | 60 months | 
| Supplemental medication | Number of supplemental glaucoma medications used at Month 60 | 60 months | 
| Adverse Events | Number of Adverse Events during the trial | 60 months |