Sustained Delivery Fluocinolone Acetonide Vitreous Implants: Long-Term Benefit in Patients with Chronic Diabetic Macular Edema

PurposeTo present the safety and efficacy of intravitreal implants releasing 0.2 μg/day fluocinolone acetonide (FAc) in patients with chronic versus nonchronic diabetic macular edema (DME). To assess ocular characteristics, anatomic changes, and re-treatment and ancillary therapies that may explain the differential treatment effect seen with intravitreal implants releasing FAc 0.2 μg/day in patients with chronic and nonchronic DME. An overall benefit-to-risk assessment for the FAc 0.2-μg/day and FAc 0.5-μg/day doses has been reported previously.DesignPreplanned subgroup analysis of chronic (duration of diagnosis, ≥3 years) and nonchronic (duration of diagnosis, <3 years) DME in patients from 2 randomized, sham injection-controlled, double-masked, multicenter clinical trials.ParticipantsPatients with persistent DME despite 1 or more macular laser treatment were randomized 1:2:2 to sham injection (n = 185), FAc 0.2 μg/day (n = 375), or FAc 0.5 μg/day (n = 393).MethodsPatients received study drug or sham injection and after 6 weeks were eligible for rescue laser. Based on re-treatment criteria, additional masked study drug could be given after 1 year.Main Outcome MeasuresPercentage of patients with improvement of 15 letters or more from baseline. Secondary outcomes included other parameters of visual function and foveal thickness.ResultsAt month 36, the difference between FAc 0.2 μg/day and sham control in the percentage of patients who gained 15 letters or more was significantly greater in chronic DME patients (FAc 0.2 μg/day, 34.0% vs. sham, 13.4%; P<0.001), compared with patients with nonchronic DME (FAc 0.2 μg/day, 22.3% vs. sham, 27.8%; P = 0.275). The greater response in patients with chronic DME was not associated with baseline ocular characteristics, changes in anatomic features, or differences in re-treatment or ancillary therapies. The ocular adverse event profile for FAc 0.2 μg/day was similar regardless of DME duration.ConclusionsThis is the first published analysis correlating duration of diagnosis of DME with treatment effect. In patients with chronic DME, FAc 0.2 μg/day provides substantial visual benefit for up to 3 years and would provide an option for patients who do not respond to other therapy.