α2 agonist slows retinal dystrophy progression

Patients with retinal dystrophy experience slower disease progression when treated with the α2 agonist brimonidine, according to a study published in the February 2008 issue of the Journal of Ocular Pharmacology and Therapeutics.

Saul Merin and team, from the Hadassah-Hebrew University Medical Center, Israel, assessed the neuroprotective effect of the topical agent in 26 patients with retinal dystrophies. One randomly selected eye was treated with brimonidine tartrate 0.2% twice-daily, while the fellow eye received artificial tears. Disease progression parameters tested at six to eight-month intervals throughout the study included Goldmann visual fields, contrast sensitivity, colour vision, and fullfield electroretinography.

Seventeen patients completed the study. At the conclusion, there were no differences detected in visual acuity, colour vision, and contrast sensitivity between the treated and control eyes. There was a trend, however, toward a lesser degree of visual field loss (VFL) in the brimonidine-treated eyes, and a delay in the time required to reach a 25% VFL in the treated eyes. These differences were more pronounced in a subgroup of patients diagnosed with retinitis pigmentosa and with visual fields of 5 cm² or more at baseline.

The team concluded that there is a trend for slower disease progression in the eyes of patients with retinal dystrophy when treated with brimonidine.