Effect of Xalacom® (Latanoprost/Timolol) and Combigan® (Brimonidine/Timolol) Fixed Combination on Intraocular Pressure and Ocular Blood Flow in Patients With Primary Open Angle Glaucoma or Ocular Hypertension

Condition(s) targeted: Retina; Ocular Physiology

Intervention: latanoprost 0.005% + timolol 0,5% fixed combination (Drug); brimonidine 0,2% + timolol 0,5% fixed combination (Drug)

Phase: N/A

Status: Completed

Sponsored by: Medical University of Vienna

Official(s) and/or principal investigator(s):
Michael Wolzt, MD, Principal Investigator, Affiliation: Department of Clinical Pharmacology, Medical University of Vienna

Glaucoma is one of the most common causes of blindness in the industrialized nations. For a long time glaucoma has been defined as a disease in which high intraocular pressure (IOP) leads to irreversible optic disc damage and subsequent visual field loss. However, recent investigations show that IOP is not the only factor that is involved in the glaucomatous process leading to retinal ganglion cell death. The role of vascular factors in the pathogenesis of glaucoma has recently received much attention based on animal experiments and epidemiological studies. The main focus of glaucoma is still directed towards a decrease in IOP. There is, however, also considerable interest whether antiglaucoma drugs influence ocular perfusion. Although measurement of ocular blood flow is still difficult, a number of innovative techniques have been realized which cover different aspects of ocular perfusion. In the present study Xalacom® (latanoprost/timolol) and the fixed combination of Combigan® (brimonidine/timolol) will be compared with respect to their IOP lowering efficacy as well as their ocular hemodynamic effects.

Official title: A Double-masked Randomized Cross-over Study Comparing of the Effect of Xalacom® (Latanoprost/Timolol)and Combigan® (Brimonidine/Timolol) Fixed Combination on Intraocular Pressure and Ocular Blood Flow in Patients With Primary Open Angle Glaucoma or Ocular Hypertension

Study design: Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Treatment

Primary outcome:

Optic disc blood flow measured with laser Doppler flowmeter (rel units)

Intraocular pressure (mmHg)

Secondary outcome:

Retrobulbar flow velocities as measured with color Doppler imaging (cm/s)

Mean defect of visual field measured with automated perimetry (dB)

Corneal thickness as measured with pachymetry (µm)

Minimum age: 18 Years. Maximum age: N/A. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Men and women over 18 years

- Unilateral or bilateral primary open angle glaucoma, ocular hypertension, exfoliation

glaucoma, pigmentary glaucoma with IOP between 22 - 35mmHg

- At least 3 reliable visual field testings

- 4 weeks for ß adrenergic receptor antagonists and prostaglandin analogues, 2 weeks

for adrenergic agonists, and 5 days for cholinergic agonists and carbonic anhydrase inhibitors Exclusion Criteria:

- History of acute angle closure

- Closed or barely open anterior chamber angle

- Mean deviation of visual field testing > 10

- Intraocular surgery or argon laser trabeculoplasty within the last six months

- Ocular inflammation or infection within the last three months

- Contact lenses

- Patients with bradycardia (heart rate < 50 beats/min)

- Second and third degree heart block

- Asthma

- COPD

- Congestive heart failure

- Severe renal impairment (creatinine clearance < 1. 8 L/h)

- History of hypersensitivity to one of the study drugs or drugs with similar chemical

structure

- Topical or systematically/oral therapy with steroids

- History of non-IOP responder to beta-blockers, alpha-2 adrenergic or prostaglandin

analogues

- Pregnancy

Department of Clinical Pharmacology, Vienna 1090, Austria

Starting date: January 2006
Last updated: November 13, 2014