Slow study recruitment and lack of clinical equipoise over time

The purpose of this study is to compare the efficacy and safety of Trabectome versus Trabeculectomy with adjunctive Mitomycin C, combined with cataract surgery, in patients with open angle glaucoma.

Background: Trabeculectomy with adjunctive use of Mitomycin C (Trab MMC) is the standard incisional procedure to lower intraocular pressure (IOP) in adults with open angle glaucoma (OAG). Trab MMC has been shown to effectively lower IOP, however, it can be associated with a number of serious complications, such as hypotony maculopathy, choroidal effusion or hemorrhage, and endophthalmitis, as well as less serious complications that may affect vision related quality of life such as bleb dysesthesia.

A newer technology, referred to as the Trabectome (NeoMedix Corp., San Juan Capistrano, CA), removes an arc of trabecular meshwork and inner wall of Schlemm's canal with microcautery and appears to lower IOP effectively with fewer and less serious complications than Trab MMC. However, more studies are needed to determine the long term safety and efficacy of this relatively new procedure.

In addition, for OAG patients with visually significant cataracts, either Trab MMC or Trabectome can be combined with cataract surgery.

Study Objective: To compare the efficacy and safety of Trabectome versus Trab MMC, in combination with cataract extraction by phacoemulsification and intraocular lens implant, for control of IOP in OAG, including pseudoexfoliative glaucoma.

Methods: Single center, single surgeon, prospective randomized controlled trial. A total of 52 eligible participants, 26 per study arm would need to be recruited for 90% power. One eye per study patient will be enrolled and randomized to Trabectome combined with cataract surgery (Trabectome-IOL) or Trab MMC combined with cataract surgery (Trab-IOL).

Postoperative visits will take place at the discretion of the surgeon but will include at least visits at day 1, week 1, and months 1, 3, 6, and 12. Postoperative glaucoma medications will be added in a stepped regimen as appropriate, along with additional laser or surgical procedures if needed.

Current Study Status: The clinical trial was terminated early due to slow recruitment and clearer indications for each technique over time leading to lack of clinical equipoise essential for patient randomization/recruitment. This had been discussed and agreed upon with our data safety monitoring board. A total of 19 participants were recruited with followup to one year. Study analysis is pending.

Inclusion Criteria:

1. Age 40-85 years
2. Open angle glaucoma (including pseudo exfoliative glaucoma)
3. Open angles (≥ Shaffer grade II)
4. Inadequately controlled IOP requiring surgical intervention
5. Visually significant cataract
6. Willing to complete quality of life questionnaires
7. Capable of informed consent and available for at least 1 year follow-up

Exclusion Criteria:

1. Any form of angle closure glaucoma
2. Secondary open angle glaucomas
3. Absence of clear angle landmarks on gonioscopy
4. Other ocular disease that may affect assessments of visual acuity, visual field, or accurate tonometry
5. Previous angle surgery or filtering procedure
6. Steroid use within the preceding 3 months
7. Presence of significant co-morbidities