Rheopheresis for age-related macular degeneration: clinical results and putative mechanism of action

Abstract

Background: Rheopheresis is being evaluated in a clinical trial. The rationale and available results are presented.

Methods: We reviewed the literature about the pathophysiology of age-related macular degeneration (AMD) that might support the use of rheopheresis. In addition, we reviewed the previously published results of the use of rheopheresis for AMD.

Results: There appears to be a diffusion barrier caused by accumulation of cross-linked proteins known as advanced macular oxidation products (AMOPS) in AMD. Rheopheresis allows removal of uncross-linked proteins and facilitates antioxidant entry into Bruch's membrane, preventing further accumulation of AMOPS. The Multicenter Investigation of Rheopheresis for AMD (MIRA-1), an ongoing double-masked randomized trial, should determine the efficacy of rheopheresis in preventing the progression of AMD. The interim results, from an analysis of visual acuity data for 43 patients, are encouraging, confirming the potential of rheopheresis as a therapeutic option for dry AMD. The benefit was evident immediately after treatment and remained essentially stable throughout the 12-month period of evaluation. Eyes with late-stage, high-risk, dry AMD appeared to be at significant risk for substantial vision loss over the 12 months if not treated. Subgroup analysis demonstrated that the timing of rheopheresis in the course of a patient's disease may have a pronounced effect on outcome.

Interpretation: There appears to be a rationale for the use of rheopheresis in AMD. Further results of the clinical trial are awaited.