Onset and duration of visual acuity improvement after dexamethasone intravitreal implant in eyes with macular edema due to retinal vein occlusion.

Purpose: To evaluate the onset and duration of improvement in best-corrected visual acuity (BCVA) in eyes treated with dexamethasone intravitreal implant 0.7 mg (DEX implant) for macular edema after branch or central retinal vein occlusion.
Methods: Post hoc analysis of data from 2 previously reported multicenter, 6-month, randomized sham-controlled clinical trials. Patients received a single DEX implant (n = 427) or sham procedure (n = 426) in the study eye. The primary endpoint was the percentage of eyes with ≥ 15-letter improvement in BCVA from baseline at postimplant Day 7.
Results: The baseline mean BCVA was 20/80. At Day 7, 10.3% of DEX implant-treated eyes versus 4.0% of sham-treated eyes (P < 0.001) had ≥ 15-letter improvement in the BCVA, and 27.2% of DEX implant-treated eyes versus 10.6% of sham-treated eyes had ≥ 10-letter improvement (P < 0.001). The mean improvement at Day 7 was 5.3 letters (branch retinal vein occlusion, 5.1; and central retinal vein occlusion, 5.8) with DEX implant and 1.6 letters (branch retinal vein occlusion, 2.3; and central retinal vein occlusion, 0.1) with sham (P < 0.001). The mean time from initial observation of ≥ 15-letter BCVA gain to the last observation of ≥ 15-letter BCVA gain was 70 days.
Conclusion: Dexamethasone intravitreal implant treatment led to improvement in BCVA compared with sham procedure as early as postimplant Day 7. The duration of ≥ 3-line improvement was typically 2 to 3 months.