Optic nerve degeneration is a major cause of irreversible blindness worldwide with glaucoma being the most common optic neuropathy, affecting approximately 76 million people worldwide in 2020. The optic nerve comprises axons of retinal ganglion cells (RGCs), the output neurons of the inner retina. Protecting RGCs and axons from degeneration and regenerating RGC axons to preserve and recover vision in patients with progressive optic neuropathy is an unmet need.