Taken together, our results indicate that ultra-long-lasting delivery of human C-peptide from an intravitreal K9-C-peptide depot had a therapeutic effect against retinal neovascularization by normalizing hyperglycemia-induced oxidative stress, microvascular leakage, VEGF/PEDF imbalance, IL-1β expression, microglial activation, and BRB disruption (Fig. 8). Here, IL1B is linked to Hyperglycemia.