Drug delivery agents consisting of polymer compounds that facilitate the delivery of pharmaceuticals for the treatment of ocular diseases and conditions, namely, uveitis, retinal vein occlusion, macular edema, macular disease, retinal disease, and glaucoma; pharmaceutical preparations for the treatment of ocular diseases and conditions, namely, uveitis, retinal vein occlusion, macular edema, macular disease, retinal disease, and glaucoma