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Note: This record shows only 22 elements of the WHO Trial Registration Data Set. To view changes that have been made to the source record, or for additional information about this trial, click on the URL below to go to the source record in the primary register.
Last refreshed on: 16 December 2017
Main ID:  NCT03274024
Date of registration: 29/08/2017
Prospective Registration: No
Primary sponsor: Singapore Eye Research Institute
Public title: The Asia Primary Tube Versus Trab (TVT) Study TVT
Scientific title: The Asia Primary Tube Versus Trab (TVT) Study
Date of first enrolment: September 28, 2016
Target sample size: 300
Recruitment status: Recruiting
Study type:  Interventional
Study design:  Allocation: Randomized. Intervention model: Parallel Assignment. Primary purpose: Treatment. Masking: Double (Participant, Investigator).  
Phase:  N/A
Countries of recruitment
Name:     Serena Ting
Telephone: (+65) 8113 5026
Name:     Natalia Porporato, Fellow
Telephone: +6591378217
Name:     Ching Lin Ho
Affiliation:  Singapore National Eye Centre
Key inclusion & exclusion criteria

Inclusion Criteria:

1. Open angle glaucoma including primary open angle glaucoma, pseudoexfoliative or
pigmentary glaucoma.

2. IOP > 18 mm Hg on 2 or more medications on at least 2 visits

3. Informed consent given and consent form signed.

Exclusion Criteria:

1. Unwilling or unable to give consent, unwilling to accept randomisation, or unable to
return for scheduled protocol visits.

2. Pregnant or nursing women

3. No light perception vision

4. Previous incisional intraocular surgery, other than uncomplicated clear corneal
cataract surgery

5. Previous ocular laser in study eye (keratorefractive surgery and cyclodestructive
procedure), except for laser trabeculoplasty procedures (Argon Laser and Selective
Laser Trabeculoplasty)

6. Iris neovascularisation or proliferative retinopathy

7. Primary angle closure or primary angle closure glaucoma

8. Iridocorneal endothelial syndrome or anterior segment dysgenesis

9. Epithelial or fibrous downgrowth

10. Aphakia

11. Chronic or recurrent uveitis

12. Severe posterior blepharitis

13. Unwilling to discontinue contact lens use after surgery

14. Glaucoma secondary to penetrating keratoplasty, trauma, steroids, retinal
disease/surgery or neovascular disease

15. Conjunctival scarring from prior ocular surgery, trauma or cicatrizing disease
precluding a superior trabeculectomy

16. 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

17. Advanced glaucoma with MD <-20dB

Age minimum: 18 Years
Age maximum: 85 Years
Gender: All
Health Condition(s) or Problem(s) studied
Device: Ahmed Glaucoma Implant
Procedure: Trabeculectomy with Mitomycin C
Primary Outcome(s)
Failure [Time Frame: 6 months]
Secondary Outcome(s)
Adverse Events [Time Frame: 60 months]
Best Corrected Visual Acuity (BCVA) [Time Frame: 60 months]
IOP [Time Frame: 60 months]
Supplemental medication [Time Frame: 60 months]
Secondary ID(s)
Source(s) of Monetary Support
Please refer to primary and secondary sponsors
Secondary Sponsor(s)
National Medical Research Council (NMRC), Singapore
Ethics review
Results available:
Date Posted:
Date Completed:
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