Prospective, Randomized, Multicentre, Open-label, Phase II / III Study to Assess Efficacy and Safety of Ranibizumab 0.5 mg Intravitreal Injections Plus Panretinal Photocoagulation (PRP) Versus PRP in Monotherapy in the Treatment of Subjects With High Risk Proliferative Diabetic Retinopathy.

This study is a prospective, randomized, multicentre, open label study that intents to compare the efficacy and safety of ranibizumab 0.5 mg Intravitreal (ITV) injections plus Panretinal Photocoagulation versus Panretinal Photocoagulation alone in the regression of the neovascularization area in patients with High Risk Proliferative Diabetic Retinopathy over a 12-month treatment period. One of the major complications of the diabetes mellitus is Diabetic Retinopathy (DR), one of the leading causes of visual impairment in working age in industrialized countries. Longer diabetes duration and poor glycaemic and blood pressure control are strongly associated with Diabetic Retinopathy. The overall prevalence of any form of Diabetic Retinopathy is 34.4% and 6.96% corresponds to Proliferative Diabetic Retinopathy (PDR). Therefore, approximately 93 million people have Diabetic Retinopathy and 17 million of them have Proliferative Diabetic Retinopathy. It has been shown that treatment with repeated injections of ranibizumab can improve visual acuity in patients with PDR. Further, , the standard PRP treatment of PDR remains unsatisfactory. The knowledge of the mechanisms of this retinal complication is incomplete and, therefore, efforts should be done to understand and characterize patients' eyes response to combined treatments. Therefore, the purpose of this study is to compare the standard treatment for PDR (i.e. Panretinal Photocoagulation) with Panretinal Photocoagulation treatment combined with ITV injections of ranibizumab since it is expected that anti-vascular endothelial growth factor (VEGF) treatment with ITV injections will increase the rate of success of Panretinal Photocoagulation in regression of neovascularization with improved final visual acuity.