This retrospective cohort study of 3277 patients receiving anti-VEGF treatment for macular oedema suggests that undesirable treatment outcomes (absence of VA improvement or VA-loss attributable to macular oedema) following anti-VEGF initiation is common in the real world and can be expected to occur in about half the patient population by the third year of treatment, in spite of appropriate loading. This evidence concerns the gene VEGFA and macular retinal edema.