Session Title: FP-15 Vascular Diseases and Diabetic Retinopathy V
Session Date/Time: Sunday 14/09/2014 | 08:00-10:00
Paper Time: 09:04
Venue: Boulevard D
First Author: : S.Sadda USA
Co Author(s): : R. Danis X.Y. Li H. Cui Y. Hashad S. Whitcup
To assess the long-term treatment effects of dexamethasone intravitreal implant [DEX implant] (Ozurdex®, Allergan Inc., Irvine, CA) 0.7-mg and 0.35-mg on retinal morphology in patients with diabetic macular oedema.
Analysis of pooled imaging data from two identical, 3-year, multicentre, randomised, sham-controlled phase III trials (NCT00168337 and NCT00168389) of the safety and efficacy of DEX implant in patients with diabetic macular oedema.
Patients with diabetic macular oedema, best-corrected visual acuity (BCVA) in the study eye of 34–68 letters (20/200–20/50 Snellen equivalent), and retinal thickness in the 1-mm central subfield (CRT) ≥300 µm were randomized to treatment with DEX implant 0.7-mg, DEX implant 0.35-mg, or sham injection, and followed for 3 years. Patients with uncontrolled diabetes (HbA1c >10%), glaucoma, or a history of steroid-induced ocular hypertension were excluded. Study visits occurred at 6-week (Year 1) and 3-month (Years 2 and 3) intervals; retreatment was permitted at ≥6-month intervals in patients with residual oedema or CRT >175 µm. Time-domain optical coherence tomography (OCT), fluorescein angiography (FA) and stereoscopic colour fundus photography (FP) were performed at pre-specified intervals over 3 years, and images were evaluated at a central reading facility by operators masked to study treatment. Outcomes of interest included changes in CRT and macular volume (OCT), presence/extent of retinal thickening, diabetic retinopathy and clinically significant macular oedema (FP), and presence/extent of fluorescein leakage and macular capillary loss (FA). Missing values were imputed using the last-observation-carried-forward (LOCF) technique.
In total, 1048 patients received a mean of 4 to 5 injections with DEX implant and sham in the study eye over 3 years. At all time points DEX implant 0.7-mg and 0.35-mg significantly reduced CRT (mean change from baseline at study end: -117.3 and -127.8 µm, respectively; mean average change [area-under-curve approach] over study period: -111.6 and -107.9 µm) and macular volume (mean change from baseline at study end: -1.06 and -1.14 mm3) (all p<0.001 vs sham). DEX 0.7-mg and 0.35-mg implant also reduced the disc area of macular thickening (mean change from baseline at study end: -2.753 and -2.931, respectively; both p<0.001 vs sham). Significantly more DEX implant 0.7-mg and 0.35-mg- than sham- treated eyes showed improvement in clinically significant macular oedema (retinal thickening ≥1 disc area, part ≤1 disc diameter from centre, or retinal thickening/adjacent hard exudates ≤500 μm from centre) at study end (20.4% and 22.4%, respectively, vs 12.4%; both p<0.05). DEX implant 0.7-mg extended time to onset of 2-step progression in diabetic retinopathy severity by ~12 months (44% risk reduction over 3 years; p=0.03 vs sham). DEX implant 0.7-mg and 0.35-mg transiently reduced fluorescein leakage in Year 1 but did not significantly affect capillary loss.
DEX implant 0.7-mg or 0.35-mg, administered at ≥6-month intervals over a 3-year treatment period, produced rapid and sustained improvement in retinal morphology in patients with diabetic macular oedema. DEX implant-treated eyes showed significant decreases in central subfield retinal thickness and macular volume compared with sham-treated eyes, with treatment effects evident as early as 3 months. Compared with sham, long-term treatment with DEX implant reduced the frequency of macular edema and delayed the time to 2-step progression in diabetic retinopathy severity.