Randomized controlled study of an intravitreous dexamethasone drug delivery system in patients with persistent macular edema.

Objective: To evaluate a dexamethasone intravitreous drug delivery system (DDS) in patients with persistent (> or =90 days despite treatment) macular edema.
Methods: This 6-month study randomized 315 patients with persistent macular edema with best-corrected visual acuity (BCVA) of 20/40 to 20/200 in the study eye to observation or a single treatment with dexamethasone DDS, 350 or 700 microg.
Main Outcome Measures: Proportion of patients achieving a BCVA improvement of 10 or more letters or 15 or more letters, safety measures, change in fluorescein angiographic leakage, and central retinal thickness.
Results: At day 90 (primary end point), an improvement in BCVA of 10 letters or more was achieved by a greater proportion of patients treated with dexamethasone DDS, 700 microg (35%) or 350 microg (24%), than observed patients (13%; P<.001 vs 700-microg group; P = .04 vs 350-microg group); an improvement in BCVA of 15 letters or more was achieved in 18% of patients treated with dexamethasone DDS, 700 microg, vs 6% of observed patients (P = .006). Results were similar in patients with diabetic retinopathy, vein occlusion, or uveitis or Irvine-Gass syndrome. During 3 months of observation, 11% of treated patients and 2% of observed patients had intraocular pressure increases of 10 mm Hg or higher.
Conclusion: In persistent macular edema, a single dexamethasone DDS treatment produced statistically significant BCVA improvements 90 days after treatment and was well tolerated for 180 days. Application to Clinical Practice Dexamethasone DDS, 700 microg, may have potential as a treatment for persistent macular edema.