Long-term Effects of Intravitreal 0.19 mg Fluocinolone Acetonide Implant on Progression and Regression of Diabetic Retinopathy

Objective To investigate the effects of fluocinolone acetonide (FAc) on the progression to proliferative diabetic retinopathy (PDR) and the impact of FAc on changes in Early Treatment Diabetic Retinopathy Study (ETDRS) diabetic retinopathy (DR) severity scale (DRSS) grade during the Fluocinolone Acetonide in Diabetic Macular Edema (FAME) A and B Phase III clinical trials. Design Post hoc analysis of data from the 36-month prospective, randomized, FAME A and B trials. Participants Patients with diabetic macular edema (DME) who received sham control or FAc 0.2 or 0.5 μg/day. Methods A masked reading center (University of Wisconsin–Madison) determined DRSS grade and retinal perfusion status using standard 7-field stereo fundus photography and fluorescein angiography, respectively. Retinopathy changes over time were determined by DRSS step differences from baseline to month 36. Pairwise comparisons between the 3 treatment groups were performed using a log-rank test without adjustment for covariates, with the primary comparison between sham control and 0.2 μg/day FAc. Main Outcome Measures Study eye progression to PDR based on a composite clinical outcome of (1) progression from nonproliferative diabetic retinopathy (NPDR) to PDR based on graded fundus photographs, (2) panretinal photocoagulation (PRP), or (3) pars plana vitrectomy (PPV) for PDR; and study eye changes on the DRSS. Results In the integrated FAME data set, compared with sham control-treated subjects, time to first PDR event was significantly delayed in subjects treated with FAc (P < 0.001), and this effect was confirmed in subgroups with more severe DR and chronic DME at baseline. In addition, subjects with retinal nonperfusion at baseline showed greater reduction in progression to PDR with FAc treatment. Both FAc dosages demonstrated statistically significant improvements in mean DR severity compared with sham treatment at months 6, 12, and 18. Numerically more subjects who received FAc experienced 2-or-more- or 3-or-more-step improvements in DR severity compared with subjects who received sham; conversely, fewer subjects treated with FAc experienced 2-or-more- or 3-or-more-step worsening in DR severity. The 3-or-more-step improvement with 0.5 μg/day FAc was statistically significantly different from sham control. Conclusions In subjects with DME, sustained intraocular delivery of FAc slows development of PDR and slows progression of diabetic retinopathy.