- ICH GCP
- US Clinical Trials Registry
- Clinical Trial NCT00815373
The Effects of Cosopt® Vs Xalacom® on Ocular Hemodynamics and Intraocular Pressure (IOP) in Primary Open-angle Glaucoma (POAG) (Xal-Cos)
A Comparative Analysis of the Effects of Cosopt® Versus Xalacom® on Ocular Hemodynamics and Intraocular Pressure in Patients With Primary Open-angle Glaucoma
Study Overview
Status
Conditions
Intervention / Treatment
Detailed Description
Background and Rationale
Apoptosis of retinal ganglion cell has been considered as the most plausible pathogenic mechanism of glaucoma. Apoptosis can be caused by neurotrophic factor withdrawal or glutamate release and both of them are triggered by elevated intraocular pressure (IOP) and ischemia simultaneously or separately.
The topical carbonic anhydrase inhibitor, Dorzolamide (Trusopt*), has recently been approved for chronic use in the treatment of glaucoma. The ocular hypotensive effects of this topical carbonic anhydrase inhibitor seem likely to produce the same results as *-adrenergic antagonists. Systemic carbonic anhydrase inhibitors are known to have vasodilatory effects (Maren,1987). Rassam S.M.B., Patel V. and Kohner E.M. (1993) have concluded that acetazolamide causes an increase in retinal blood flow in the human retinal circulation. It has also been demonstrated that Trusopt* increases retinal circulation as measured by scanning laser ophthalmoscopy (SLO) (Harris, Arend, Martin, 1996). Furthermore, Trusopt increases arteriovenous passage (AVP) time and improves contrast sensitivity in normal tension glaucoma patients (Harris, 1999).
Cosopt* (dorzolamide hydrochloride-timolol maleate ophthalmic solution) is combination of a topical carbonic anhydrase inhibitor and a topical beta-adrenergic receptor blocking agent. Each of these two components reduces intraocular pressure. The IOP-reducing effect of Cosopt b.i.d. was greater (1-3 mm Hg) than that of monotherapy with either 2.0 % dorzolamide t.i.d. or 0.5 % timolol b.i.d. The IOP-lowering effect of Cosopt* b.i.d. was approximately 1 mm Hg less than that of concomitant therapy with 2.0% dorzolamide t.i.d. and 0.5 % timolol b.i.d. A previous study showed that the retinal circulation (AVP time) was significantly accelerated after replacing Timoptic* with Cosopt* in glaucoma patients (Harris, 1999).
Latanoprost (Xalatan*) is a prostaglandin F2* analogue which is believed to reduce IOP by increasing the outflow of aqueous humor. The retinal vascular effects of Latanoprost, however, remain unclear. While some studies have shown PGF2* to induce constriction in bovine isolated aqueous veins (Nielsen 1996), other studies have been unable to demonstrate an effect on retrobulbar flow velocities (Drance 1996). It is possible that vasoconstrictive properties of the drug may produce a negative impact on previously ischemic retinal tissue or at best no change.
In a recent study comparing Trusopt® with Xalatan® some very encouraging results emerged, AVP time was significantly reduced with Trusopt®, but not with Xalatan® despite the fact that Xalatan® increases perfusion pressure (due to IOP) more than Trusopt®. This is the strongest evidence so far of a pressure independent effect of Trusopt® on ocular blood flow.
Objectives
- To compare the IOP efficacy of Cosopt® and Xalacom® on IOP.
- To determine the perfusion pressure effect of Cosopt® and Xalacom®.
- To determine the blood flow effect of the two drugs on the ophthalmic, central retinal and short posterior ciliary arteries, using Color Doppler Imaging (CDI).
Study Type
Phase
- Not Applicable
Contacts and Locations
Study Locations
-
-
-
Kfar Saba, Israel
- Meir Medical Center
-
-
Participation Criteria
Eligibility Criteria
Ages Eligible for Study
Accepts Healthy Volunteers
Genders Eligible for Study
Description
Inclusion Criteria:
- 18 years of age or greater.
- Patient signed an informed consent agreement.
- Corrected visual acuity of 6/12 or better:
- Characteristic glaucomatous visual-field loss and optic nerve head damage in one or both eyes.
- Either IOP measurements ≥21 mmHg in the 3 months prior to study entry or IOP ≥ 21 mmHg at the end of the washout period
- Patient on ≥1 IOP reducing agents. -
Exclusion Criteria:
- Past history of ocular diseases (other than OAG / Cataract / Refractive error).
- Past history of orbital/ocular surgery or trauma.
- Receiving ≥ 3 IOP reducing agents.
- Receiving agents known to produce significant cardiovascular, respiratory, renal or hepatic side effects.
- Personal history of respiratory disease such as asthma, emphysema or other chronic obstructive pulmonary disease.
- Personal history of congestive heart failure.
- Personal history of bradycardia or 2nd and 3rd degree AV block.
- Known allergy to sulfa.
- Women who are pregnant or nursing.
- Women who of child bearing age who are planning to become pregnant within one month after study completion.
- Receiving Levitra, Viagra, Cialis or other erectile dysfunction drugs.
Study Plan
How is the study designed?
Design Details
- Allocation: RANDOMIZED
- Interventional Model: CROSSOVER
- Masking: QUADRUPLE
Arms and Interventions
Participant Group / Arm |
Intervention / Treatment |
---|---|
ACTIVE_COMPARATOR: 1
Cosopt* b. i. d. (dosed morning and bedtime) will be administered topically
|
Cosopt* b. i. d.
Other Names:
|
ACTIVE_COMPARATOR: 2
Xalacom* q.d.(dosed bedtime) and placebo vehicle q.d.
(dosed morning) topically in the other group
|
Xalacom* QHS
Other Names:
|
What is the study measuring?
Primary Outcome Measures
Outcome Measure |
Time Frame |
---|---|
Ocular hemodynamics as measured by Color Doppler imaging
Time Frame: 3 years
|
3 years
|
Secondary Outcome Measures
Outcome Measure |
Time Frame |
---|---|
Intraocular pressure as measured by Goldmann applanation tonometry
Time Frame: 3 Years
|
3 Years
|
Collaborators and Investigators
Sponsor
Investigators
- Principal Investigator: Adi Abulafia, MD, Meir Medical Center, Tel Aviv University
Study record dates
Study Major Dates
Study Start
Primary Completion (ANTICIPATED)
Study Completion (ANTICIPATED)
Study Registration Dates
First Submitted
First Submitted That Met QC Criteria
First Posted (ESTIMATE)
Study Record Updates
Last Update Posted (ESTIMATE)
Last Update Submitted That Met QC Criteria
Last Verified
More Information
Terms related to this study
Additional Relevant MeSH Terms
- Cardiovascular Diseases
- Vascular Diseases
- Eye Diseases
- Glaucoma
- Glaucoma, Open-Angle
- Ocular Hypertension
- Hypertension
- Physiological Effects of Drugs
- Adrenergic beta-Antagonists
- Adrenergic Antagonists
- Adrenergic Agents
- Neurotransmitter Agents
- Molecular Mechanisms of Pharmacological Action
- Anti-Arrhythmia Agents
- Antihypertensive Agents
- Enzyme Inhibitors
- Carbonic Anhydrase Inhibitors
- Pharmaceutical Solutions
- Ophthalmic Solutions
- Timolol
- Dorzolamide
- Maleic acid
- Latanoprost
Other Study ID Numbers
- 0155-08-MMC
This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.
Clinical Trials on Ocular Hypertension
-
Western Galilee Hospital-NahariyaUnknown
-
Laboratoires TheaCompletedOcular Hypertension GlaucomaBulgaria
-
Santen Inc.Completed
-
West Virginia UniversityUniversity of PittsburghRecruitingGlaucoma and Ocular HypertensionUnited States, United Kingdom, Canada
-
University Hospital, GenevaTerminatedGlaucoma and Ocular HypertensionSwitzerland
-
Santen Inc.Completed
-
Maastricht University Medical CenterCompletedCorticosteroid Induced Ocular Hypertension/GlaucomaNetherlands
-
Santen Inc.CompletedA Study Assessing the Safety and Efficacy of DE-117 Ophthalmic Solution in Patients With POAG or OHTGlaucoma and Ocular HypertensionUnited States
-
Bausch & Lomb IncorporatedCompletedGlaucoma | Open Angle or Ocular HypertensionUnited States
-
Nicox Ophthalmics, Inc.CompletedGlaucoma, Open-Angle | Hypertension, OcularUnited States
Clinical Trials on Dorzolamide+Timolol Maleate0.5%
-
Merck Sharp & Dohme LLCCompletedOcular Hypertension | Glaucoma
-
Laboratorios PoenRecruitingOcular Hypertension | Glaucoma, Open-AngleArgentina
-
Merck Sharp & Dohme LLCCompleted
-
Aristotle University Of ThessalonikiCompletedOpen-angle GlaucomaGreece
-
Pharmaceutical Research NetworkCompletedOcular Hypertension | Open-Angle Glaucoma | Exfoliation Syndrome | Glaucoma, PigmentaryUnited States
-
Wills EyeMid Atlantic Retina; J. Arch McNamara Research FundCompletedAge-related Macular Degeneration | Diabetic Macular Edema | Retinal Vein Occlusion | Wet Macular DegenerationUnited States
-
Alcon ResearchCompletedOcular Hypertension | GlaucomaCanada
-
Afyon Kocatepe University HospitalCompleted
-
University of California, Los AngelesCompletedGlaucomaUnited States
-
Universitaire Ziekenhuizen KU LeuvenUnknownOpen Angle GlaucomaBelgium