Dexamethasone Implant for Retinal Detachment in Uveal Melanoma

Overview

This is an investigator-initiated Phase I study of a single dose of an intravitreally-administered dexamethasone implant (Ozurdex™) in subjects with uveal melanomas (UM) and exudative retinal detachments (ERD: build-up of fluid under the retina that causes it to detach) being treated with proton beam radiation (PBI) or plaque radiotherapy. Although PBI is an effective treatment for UM, ERDs may persist after radiation, leading to vision loss. Effective treatments for ERD are currently lacking. We are conducting this study to evaluate whether Ozurdex™ can help resolve ERDs that occur in patients with UM. Ozurdex™ has been approved by the Food and Drug Administration (FDA) to treat certain ocular conditions such as macular edema, non-infectious uveitis, and diabetic macular edema but it is not approved for use in patients with UM and ERD. This study will determine the safety of the dexamethasone implant and provide preliminary evidence of efficacy in this population.

Study Objective: The primary objective of the study will be to determine the safety of the Ozurdex (dexamethasone) intravitreal implant. The secondary objective is to determine if the implant helps to resolve exudative retinal detachment, a secondary complication associated with uveal melanoma. Background: This is a single site investigator-initiated Phase I study of a single dose of intravitreally administered dexamethasone implant (Ozurdex™) in subjects with choroidal melanomas and exudative retinal detachments being treated with proton beam irradiation or plaque radiation therapy. This is one of the first studies to evaluate the Ozurdex™ implant in this setting. Therefore the primary goal is to evaluate safety. Patient Population: Twenty patients will be enrolled in this randomized pilot study. Patients must meet the following eligibility criteria to enroll: Tumor thickness ≤ 10 mm, associated serous retinal detachment \> two clock hours in extent, primary treatment of ocular melanoma with proton irradiation or plaque radiotherapy. Males and females \>18 years of age are eligible. Methods: Patients will be randomized (1:1) to receive the dexamethasone implant or no treatment. A stratified randomization scheme will be performed, with strata defined by tumor height (\< 5mm and 5mm - ≤ 10 mm). Patients will be masked to their treatment assignment. Patients will be randomly assigned to receive Ozurdex™ (0.7 mg dexamethasone) or no treatment at either (1) the time of their tumor localization (tantalum ring placement) surgery before proton therapy or (2) their surgery removing the plaque following plaque radiotherapy. A sham treatment procedure to maintain the mask will be unnecessary. Patients will be followed at 6 weeks, 14 weeks, 28 weeks and 54 weeks after administration of the dexamethasone implant. Visual acuity, intraocular pressure, optical coherence tomography, B-scan ultrasonography, wide-angle color photography and full ophthalmological examination will be performed pre-op and on every follow-up visit. Evaluation of adverse events and review of medical history and medication use will be completed at all follow-up visits. The primary outcome of the study will be to evaluate the safety of the implant. This will be done by monitoring for all adverse effects not related to the melanoma or radiation treatment including significant vision loss, other sight-threatening events, and unforeseen systemic events. Secondary endpoints include resolution of retinal detachment at 6 and 12 months after implant insertion, visual acuity at 6 and 12 months after implant insertion, and development of iris neovascularization and neovascular glaucoma during the 12 month study period. Statistical Analysis Plan: There is no formal sample size calculation in a pilot/phase I study. As this is a phase I study, a sample size of 20 patients is chosen, making sure that it is feasible financially and logistically to conduct the study. Safety Endpoints: Incidence and severity of ocular and systemic adverse events identified by ocular examination, diagnostic tests, and subject reporting will be summarized. Comparisons of these endpoints of study subjects who received treatment may be made with those of control subjects, matched on prognostic factors including tumor size and tumor location. The proportion of treated patients with adverse events will be tabulated by body system, stratified by tumor size and location, and compared to patients in the control arm using Fisher's exact test and other appropriate tests of association. Efficacy Endpoints: Descriptive statistics will be generated to assess resolution of exudative retinal detachment at 6 months after placement of the Ozurdex implant or no treatment. This is the most important efficacy endpoint. Descriptive statistics will be generated for the following secondary efficacy endpoints: incidence of neovascular glaucoma, incidence of rubeosis, percent of patients with exudative retinal detachment at 12 months, and distribution of visual acuity measures at 6 months and 12 months. All measures will be compared between patients in the treatment arm and those in the control arm of the study.