Comparative Multicenter Randomized Study of Aflibercept Versus Placebo in Macular Telangiectasia Type 1

Idiopathic juxtafoveal telangiectasia type 1 is a rare unilateral disease that mostly affects men before 50 years of age. Mac Tel 1 are characterized by microvascular telangiectasia and increased tortuosity of the macular capillary network on the temporal part of the fovea that can be identified on fundus examination. It can be associated with peripheral vascular changes, similar to manifestations of Coats' disease. It can be complicated by macular edema due to leakage from microvascular ectasia. When associated with visual loss, macular edema can be treated with different strategies although there is no consensus about the best approach. Laser can be performed on leaky aneurysms with questionable long term efficacy and potential irreversible adverse effects. Recently, anti-VEGF agents have been put forward as particularly good candidates to treat this macular edema, as observed in vein occlusion or diabetic macular edema. Indeed, in limited case series, the first anti-VEGF agents (ranibizumab and bevacizumab) showed mitigated results. More recently, authors have reported some favorable results with aflibercept in patients refractory to other anti-VEGF agents. Indeed a recent study reported both good anatomical and functional results in macular edema due to Mac Tel 1 in a non-comparative study that included 8 patients and carried out a concomitant quantification of growth factors. As an explanation, the authors found that levels of placental growth factor (PlGF), which is targeted by aflibercept but not by other anti-VEGF agents, were decreased after treatment. Moreover, PlGF correlated with capillary plexus densities assessed by OCTA. The aim of this study is thus to assess the efficacy of a 6 months treatment by aflibercept compared to placebo in macular edema linked to Mac Tel 1 with a multicenter double-blind randomized clinical trial.