Abstract
Purpose: :
This is a prospective, randomized, double-masked, multi-center study to evaluate 31 patients with Diabetic Macular Edema following implantation of I-vation TA (Triamcinolone Acetonide).
Methods: :
The I-vation TA implant was designed to provide controlled delivery of therapeutics to the back of the eye for up to 2 years. In this Phase I study, patients were randomized to either a slow-release or fast-release formulation, each containing 925 µg triamcinolone, and stratified by baseline visual acuity and presence or absence of prior laser treatment. Macular edema was determined by clinically observable macular edema associated with diabetic retinopathy, visual acuity of 20/40 or worse, retinal thickening in the fovea and by angiographic evidence of leakage involving the perifoveal capillary net.
Results: :
At 15 months, 25 of 31 patients remained in the study: 12 patients (12 eyes) in the slow-release group, 13 patients (13 eyes) in the fast-release group. The mean IOP increased from 13.9 mmHg at baseline to 16.8 mmHg in the slow group, and 14.3 mmHg at baseline to 17.8 mmHg in the fast group. The proportion of patients with BCVA of at least 70 ETDRS letters with the study eye increased from 14% to 36% in the slow group and from 18% to 38% in the fast group from baseline to 15 months. The mean macular thickness, measured as the center foveal minimum by OCT, decreased in the slow group from 529 µm at baseline to 378 µm, and in the fast group from 376 µm at baseline to 279 µm at 15 months. A decrease of at least 50 µm was reported for 67% of patients in the slow group and 58% of patients in the fast group; the largest decrease was 427 µm at 15 months compared to baseline. The most commonly reported procedural adverse event (AE) was conjunctival hemorrhage (90.4%). The most commonly reported medication-related AE was lenticular opacities (35.5%). One case of SAE (endophthalmitis) was reported in a patient two days following a retreatment procedure performed 15 months after initial implant, and was determined to be a complication of the procedure.
Conclusions: :
Results of the 15 month interim analysis suggest that both the slow- and fast-release formulations of I-vation TA are well-tolerated as evaluated by the occurrence of adverse events and IOP changes. Both formulations also appear to be associated with improvements in BCVA and macular thickness.
Keywords: diabetes • macula/fovea • edema