A Study to Evaluate THR-687 Treatment for Diabetic Macular Oedema.

The subjects in this study will be subjects with central-involved DME (CI-DME). Both treatment-naïve and previously treated subjects will be included. Inclusion Criteria: * Written informed consent obtained from the subject prior to screening procedures * Male or female aged 18 years or older at the time of signing the informed consent * Type 1 or type 2 diabetes * BCVA ETDRS letter score ≥ 39 in the study eye * CI-DME with CST of ≥ 300µm in men (or equivalent in women), measured from RPE to ILM inclusively, on SD-OCT, in the study eye * BCVA ETDRS letter score ≥ 34 in the fellow eye Exclusion Criteria: * Macular edema due to causes other than DME in the study eye * Concurrent disease in the study eye, other than DME, that could require medical or surgical intervention during the study period or could confound interpretation of the results * Any condition in the study eye that could confound the ability to detect the efficacy of the investigational medicinal product * Previous confounding medications / interventions, or their planned administration during the study * Presence of iris neovascularisation in the study eye * Uncontrolled glaucoma in the study eye * Previously received THR-687 or any other experimental therapy for DME, in either eye * Any active or suspected ocular or periocular infection, or active intraocular inflammation, in either eye * Untreated Diabetes * Glycated haemoglobin A (HbA1c) \> 12% * Uncontrolled hypertension