This study evaluates the safety and preliminary efficacy of topical sterile human insulin eye drops (EYED-002) in patients with open-angle glaucoma. The study uses a phase 1/2 dose-escalation design followed by a masked, randomized, placebo-controlled phase. Insulin is formulated as preservative-free eye drops and delivered once daily. The primary objective is to determine the safety profile of topical insulin; secondary objectives assess effects on retinal structure, visual field, visual acuity, contrast sensitivity, and quality of life.