Multicenter prospective, randomized, double-masked, placebo-controlled study of Rheopheresis to treat nonexudative age-related macular degeneration: interim analysis

Abstract

Objective: To evaluate the safety and efficacy of Rheopheresis blood filtration to treat intermediate- to late-stage preangiogenic age-related macular degeneration (AMD) with soft drusen.

Design: Multicenter, prospective, randomized, double-masked, placebo-controlled clinical trial.

Participants: First 43 randomized patients (28 Rheopheresis and 15 placebo-control patients) with available baseline and 3-month postbaseline best corrected visual acuity (BCVA) measurements and intermediate- to late-stage preangiogenic AMD with multiple large soft drusen and elevated serum levels of targeted macromolecules.

Intervention: Patients were randomly assigned to receive eight Rheopheresis or eight placebo procedures over 10 weeks.

Main outcome measures: ETDRS BCVA measurements at baseline, 3, 6, 9, and 12 months postbaseline.

Results: In primary eyes, the mean LogMAR line difference between Rheopheresis and placebo-control eyes was 1.6 lines at 12 months postbaseline; the difference was significant throughout the first posttreatment year (P = .0011, repeated measures analysis). Thirteen percent of Rheopheresis compared with 0% of placebo-control eyes had a > or = 3-line improvement in BCVA at 12 months postbaseline. Four percent of Rheopheresis compared with 18% of placebo-control eyes had a > or = 3-line loss in BCVA. The subgroup of patients whose primary eyes had baseline BCVA worse than 20/40 demonstrated a mean LogMAR difference between Rheopheresis and placebo-control eyes equaling 3.0 lines at 12 months postbaseline; the difference was significant throughout the first posttreatment year (P = .0014, repeated measures analysis). Sixteen percent of Rheopheresis compared with 0% of the placebo-control eyes had a > or = 3-line improvement in BCVA at 12 months postbaseline. Five percent of Rheopheresis compared with 29% of placebo-control eyes had a > or = 3-line loss in BCVA. Fifty-eight percent of Rheopheresis eyes improved to 20/40 or better, compared with 14% of placebo-control eyes. No serious treatment-related adverse events were observed.

Conclusions: Rheopheresis demonstrated statistically significant and clinically relevant effects on BCVA when compared with placebo controls for the 12-month study interval. Untreated patients with BCVA worse than 20/40 with intermediate- to late-stage preangiogenic AMD, soft drusen, and elevated blood factors were at risk for substantial visual loss. A sample size larger than 43 patients is important to provide a basis for widespread adoption of novel therapeutic options for AMD such as Rheopheresis. Therefore, enrollment to 150 patients is continuing.