INS and neurodegenerative disease: A study aiming to explore the safety of topical insulin eyedrops in glaucoma is registered on ClinicalTrials.gov (NCT041189200); however, the trial is not yet recruiting. The positive outcomes of the use of exogenous insulin in preclinical and clinical studies and the pathologic similarities between these age-related neurodegenerative diseases make the use of exogeneous insulin a promising potential therapeutic strategy in slowing neurodegeneration in glaucoma.