Relation Between Intraocular Pressure Lowering Effects of Topical Brimonidine and Alpha 2 Receptor Polymorphism

The recruitment status of this study is unknown because the information has not been verified recently.
Verified July 2008 by Medical University of Vienna.
Recruitment status was  Recruiting
Sponsor:
Information provided by:
Medical University of Vienna
ClinicalTrials.gov Identifier:
NCT00712777
First received: July 8, 2008
Last updated: July 9, 2008
Last verified: July 2008
  Purpose

Topical brimonidine is a recently introduced alpha 2 receptor agonist which is used in the therapy of intraocular pressure (IOP) reduction in patients with open angle glaucoma. Although adequate IOP reduction is achieved in many patients there is a considerable degree of variability in IOP reduction among subjects. The reason for this interindividual variability is not entirely clear. Obviously differences in pharmacokinetic properties due to variable penetration of the drug through the cornea may be responsible. Alternatively, polymorphisms of the alpha-2 receptor may account for the differences in IOP-lowering efficacy of topical brimonidine. This hypothesis is tested in the present study. Polymorphisms of the alpha-2 receptor have been described in a number of previous studies. In addition, polymorphisms in the alpha-2 receptor gene have been shown to be functionally important, particularly a polymorphism of the alpha-2B receptor, which has a high allele frequency in caucasians.


Condition Intervention
Ocular Physiology
Intraocular Pressure
Drug: Brimonidine 0.2 %

Study Type: Interventional
Study Design: Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Diagnostic
Official Title: Relation Between Intraocular Pressure Lowering Effects of Topical Brimonidine and Alpha 2 Receptor Polymorphism

Resource links provided by NLM:


Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:
  • Intraocular pressure (IOP) [ Time Frame: in total 10 minutes ] [ Designated as safety issue: No ]
  • alpha-2B receptor genotyping [ Time Frame: 20 minutes ] [ Designated as safety issue: No ]

Estimated Enrollment: 80
Study Start Date: March 2008
Estimated Study Completion Date: September 2009
Estimated Primary Completion Date: September 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1
homozygote mutant: Insertion/Insertion (40 patients)
Drug: Brimonidine 0.2 %
Brimonidine 0.2 % (Alphagan, Irvine, CA, USA), dose: 1 drop per eye
Active Comparator: 2
homozygote mutant: Deletion/Deletion (40 patients)
Drug: Brimonidine 0.2 %
Brimonidine 0.2 % (Alphagan, Irvine, CA, USA), dose: 1 drop per eye

  Eligibility

Ages Eligible for Study:   19 Years to 35 Years
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Men aged between 19 and 35 years, nonsmokers
  • Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
  • IOP between 12 and 16 mmHg
  • Normal ophthalmic findings, ametropia < 3 Dpt.
  • Results of alpha-2B receptor genotyping; subjects who fall within one of the following groups: group 1: homozygote mutant: I/I (n=40); group 2: homozygote mutant: D/D (n=40)

Exclusion Criteria:

  • Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
  • Treatment in the previous 3 weeks with any drug
  • Symptoms of a clinically relevant illness in the 3 weeks before the first study day
  • History of hypersensitivity to the trial drug or to drugs with a similar chemical structure
  • History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with, distribution, metabolism or excretion of study drugs
  • Blood donation during the previous 3 weeks
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00712777

Contacts
Contact: Gerhard Garhofer, MD 0043 1 40400 ext 2981 klin-pharmakologie@meduniwien.ac.at

Locations
Austria
Department of Clinical Pharmacology Recruiting
Vienna, Austria, 1090
Sponsors and Collaborators
Medical University of Vienna
  More Information

No publications provided

Responsible Party: Gabriele Fuchsjäger-Mayrl, MD, Department of Clinical Pharmacology
ClinicalTrials.gov Identifier: NCT00712777     History of Changes
Other Study ID Numbers: OPHT-230408
Study First Received: July 8, 2008
Last Updated: July 9, 2008
Health Authority: Austria: Agency for Health and Food Safety

Keywords provided by Medical University of Vienna:
Brimonidine
alpha 2 receptor polymorphism
Intraocular Pressure

Additional relevant MeSH terms:
Brimonidine
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Adrenergic Agonists
Adrenergic Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
Physiological Effects of Drugs
Antihypertensive Agents
Cardiovascular Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on April 17, 2014