Trial Outcomes & Findings for Effect of Cosopt Versus Combigan on Retinal Vascular Autoregulation in Primary Open Angle Glaucoma (POAG) (NCT NCT00824824)
NCT ID: NCT00824824
Last Updated: 2017-04-04
Results Overview
We determined whether RVD was present in the following way. The difference between the retinal blood flow measured while reclining for 30 minutes and the baseline retinal blood flow measured while seated was calculated. In a previous study, we found that among healthy subjects the change in the blood flow while reclining compared to baseline was +6.5% ± 12%. For this study, we defined the normal range of blood flow autoregulation as ± 2 standard deviations about the mean percentage change found in the control group in the initial study (6.5% ± 24.0%); that is, as -17.5% to +30.5%. Participants with a change in retinal blood flow induced by posture change outside this range were randomized to either dorzolamide-timolol fixed combination BID OU or brimonidine-timolol fixed combination BID OU for 6 weeks.
COMPLETED
NA
21 participants
6 weeks post treatment
2017-04-04
Participant Flow
A total of 21 primary open angle glaucoma patients were recruited for the study from the practices of Douglas J. Rhee, Angela V. Turalba, and Louis R. Pasquale at Massachusetts Eye and Ear Infirmary, Boston. Recruitment took place between February 13, 2009 and December 21, 2011.
Prior to the initial testing visit, subjects ceased using their current IOP-lowering medications and were run in for 6 weeks on timolol 0.5% BID OU. After this 6 week period baseline measurements were taken and 7 were identified with retinal vascular dysregulation. These 7 patients were then randomized into one of two treatment arms.
Participant milestones
| Measure |
Dorzolamide-Timolol Then Brimonidine-Timolol
4 of the 7 POAG subjects with RVD were randomized into the dorzolamide hydrochloride 2% - timolol 0.5% ophthalmic solution. The 4 subjects received this treatment for 6 weeks. After the 6-week period the same measurements that were taken at baseline where taken once again. After these measurements were collected these 4 subjects were treated with brimonidine tartrate 0.2%-timolol maleate 0.5% ophthalmic solution for 6 weeks. After this second 6 week period the same measurements that were taken previously were taken again.
|
Brimonidine-Timolol Then Dorzolamide-Timolol
3 of the 7 POAG RVD subjects were ransomized into the brimonidine tartrate 0.2%-timolol maleate 0.5% ophthalmic solution. The 3 subjects received this treatment for 6 weeks. After the 6-week period the same measurements that were taken at baseline where taken once again. After these measurements were collected these 3 subjects were treated with dorzolamide hydrochloride 2% - timolol 0.5% ophthalmic solution for 6 weeks.After this second 6 week treatment period the same measurements where taken again.
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|---|---|---|
|
Overall Study
STARTED
|
4
|
3
|
|
Overall Study
COMPLETED
|
4
|
3
|
|
Overall Study
NOT COMPLETED
|
0
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Effect of Cosopt Versus Combigan on Retinal Vascular Autoregulation in Primary Open Angle Glaucoma (POAG)
Baseline characteristics by cohort
| Measure |
Primary Open Angle Glaucoma
n=14 Participants
Subjects of either gender with age range 40 to 80 years old with POAG were eligible for the study. Eligible subjects had a history of an untreated IOP \> 21 mmHg in the left eye and a CPSD ≥ 1.0 in this eye. Patients being treated with more than two IOP lowering medications concurrently were excluded. All eligible subjects had open angles on gonioscopy with the filtering portion of the trabecular meshwork visible for 360° in both eyes. All subjects also had at least two reliable Humphrey 24-2 full threshold visual fields that showed reproducible loss in the left eye on tests with fixation loss ≤33%, false positives ≤ 20% and false negatives ≤ 20%. Patients with evidence of exfoliation or pigment dispersion syndrome in either eye were excluded. Subjects with diabetic retinopathy or a history of ocular laser or incisional surgery in either eye were also excluded.
|
POAG With RVD
n=7 Participants
7 subjects with POAG were identified to have retinal vascular dysregulation (RVD). We determined whether RVD was present in the following way. The percentage change between the retinal blood flow measured while reclining for 30 min and the baseline retinal blood flow measured while seated was calculated. In a previous study, we found that among healthy subjects the change in the retinal blood flow while reclining compared to sitting was +6.5% ± 12%. For this study, we defined the normal range of blood flow autoregulation as ±2 standard deviations about the mean percentage change found in the control group in our previous study. Subjects with a change in retinal blood flow induced by posture change outside of -17.5% to +35.5% where considered to have RVD.
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Total
n=21 Participants
Total of all reporting groups
|
|---|---|---|---|
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Age, Continuous
|
64.5 years
STANDARD_DEVIATION 8.2 • n=93 Participants
|
60.0 years
STANDARD_DEVIATION 8.6 • n=4 Participants
|
63 years
STANDARD_DEVIATION 8.3 • n=27 Participants
|
|
Sex: Female, Male
Female
|
3 Participants
n=93 Participants
|
2 Participants
n=4 Participants
|
5 Participants
n=27 Participants
|
|
Sex: Female, Male
Male
|
11 Participants
n=93 Participants
|
5 Participants
n=4 Participants
|
16 Participants
n=27 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Asian
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Black or African American
|
1 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
1 Participants
n=27 Participants
|
|
Race (NIH/OMB)
White
|
13 Participants
n=93 Participants
|
7 Participants
n=4 Participants
|
20 Participants
n=27 Participants
|
|
Race (NIH/OMB)
More than one race
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Region of Enrollment
United States
|
14 participants
n=93 Participants
|
7 participants
n=4 Participants
|
21 participants
n=27 Participants
|
PRIMARY outcome
Timeframe: 6 weeks post treatmentPopulation: 21 participants were tested for RVD after 6 weeks of timolol treatment. Of the 21 participants who were tested, 7 had RVD and were randomized to Dorzolamide-Timolol and Brimonidine-Timolol; 14 had normal autoregulation. One participant was removed from the analysis in the Brimonidine-Timolol arm due to technical difficulties with equipment.
We determined whether RVD was present in the following way. The difference between the retinal blood flow measured while reclining for 30 minutes and the baseline retinal blood flow measured while seated was calculated. In a previous study, we found that among healthy subjects the change in the blood flow while reclining compared to baseline was +6.5% ± 12%. For this study, we defined the normal range of blood flow autoregulation as ± 2 standard deviations about the mean percentage change found in the control group in the initial study (6.5% ± 24.0%); that is, as -17.5% to +30.5%. Participants with a change in retinal blood flow induced by posture change outside this range were randomized to either dorzolamide-timolol fixed combination BID OU or brimonidine-timolol fixed combination BID OU for 6 weeks.
Outcome measures
| Measure |
Dorzolamide-Timolol
n=7 Participants
Post timolol-dorzolamide outcome: All 7 patients who had RVD following timolol had retinal vascular autoregulation that was in the normal range.
|
Brimonidine-Timolol
n=6 Participants
Post timolol-brimonidine outcome: 6 of the 7 patients were tested following timolol-brimonidine. One of the 7 patients could not be tested due to technical issues. Of the 6 that were tested, 4 patients had retinal vascular autoregulation that was in the normal range. Two patients continued to show RVD.
|
|---|---|---|
|
Presence of Retinal Vascular Dysregulation (RVD)
|
7 Participants
|
4 Participants
|
Adverse Events
Dorzolamide-Timolol Then Brimonidine-Timolol
Brimonidine-Timolol Then Dorzolamide-Timolol
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Louis R. Pasquale, MD
Massachusetts Eye and Ear Infirmary
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place