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

November 20, 2014 updated by: Medical University of Vienna
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.

Study Overview

Status

Withdrawn

Conditions

Intervention / Treatment

Study Type

Interventional

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Austria
      • Vienna, Austria, 1090
        • Department of Clinical Pharmacology

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

19 years to 35 years (Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

Male

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Diagnostic
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
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

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Intraocular pressure (IOP)
Time Frame: in total 10 minutes
in total 10 minutes
alpha-2B receptor genotyping
Time Frame: 20 minutes
20 minutes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medical University of Vienna

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

March 1, 2008

Primary Completion (Actual)

November 1, 2014

Study Completion (Actual)

November 1, 2014

Study Registration Dates

First Submitted

July 8, 2008

First Submitted That Met QC Criteria

July 9, 2008

First Posted (Estimate)

July 10, 2008

Study Record Updates

Last Update Posted (Estimate)

November 21, 2014

Last Update Submitted That Met QC Criteria

November 20, 2014

Last Verified

November 1, 2014

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • OPHT-230408

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.

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