The present invention relates to compositions and methods for inhibiting loss of a retinal ganglion cell in a subject, comprising non-invasively applying to the surface of the eye of the subject an ophthalmic composition comprising a therapeutically effective amount of at 5 least one siRNA which down regulates expression of a target gene associated with loss of the retinal ganglion cell, thereby inhibiting loss of the retinal ganglion cell in the subject. The methods of the invention also relate to the use of chemically modified siRNA compounds possessing structural motifs which down-regulate the expression of human genes expressed in retinal tissue in the mammalian eye.