Disease modification, other benefits
Evidence that corticosteroid treatment can prevent progression to proliferative diabetic retinopathy (PDR) comes from the fluocinolone acetonide implant pivotal studies in which time-to-first progression to PDR was significantly reduced in eyes implanted with the fluocinolone implant compared with the sham-treated controls.
“In addition, time-to-first progression was also significantly reduced in the subset of patients with significant capillary loss, who are at the highest risk of developing proliferative disease over time,” Dr. Singh said.
A benefit of corticosteroid therapy for reducing DME and improving best-corrected visual acuity (BCVA) in patients who failed anti-VEGF therapy was reported in some small studies, but also shown in a recently published meta-analysis by Khan et al. that included 3,859 patients with recalcitrant DME treated with intravitreal sustained-release dexamethasone (Ozurdex, Allergan) [Ophthalmic Surg Lasers Imaging Retina. 2017;48(2):160-166.].
Although intravitreal corticosteroid treatment is associated with elevation in intraocular pressure (IOP), clinical trial results provide an understanding of the response and risk factors, Dr. Singh said.
Data from studies investigating the dexamethasone implant show that IOP increases most often after the first injection, but a corticosteroid IOP response is less likely to occur with repeat injections. Elevated IOP returns towards baseline by 6 months when the implant has released its medication load.
Also, noteworthy are data from the fluocinolone acetonide implant pivotal studies that showed patients with prior intravitreal exposure to corticosteroids were less likely than their counterparts without such a history to need surgical intervention for glaucoma after implantation of the fluocinolone acetonide implant.
Information about the incidence and risk factors for ocular hypertension in eyes treated with the dexamethasone implant is available from the SAFODEX study that showed eyes with pre-existing glaucoma receiving dual or triple therapy had a higher rate of elevated IOP [Retina. 2016 Oct 20. Epub ahead of print].