title: Biodegradable intraocular therapies for retinal disorders: progress to date.
abstract: In general, it is difficult to achieve effective levels of drugs in the vitreous and the retina via topical and/or systemic administration. Intraocular drug delivery systems that achieve longer duration of pharmacological effect with lower administration frequency are urgently needed. Intraocular sustained drug release via implantable devices or injectable particles has been investigated for the treatment of various vitreoretinal disorders. Several non-biodegradable implants are available in clinical practice or in the late developmental phase: Vitrasert (ganciclovir intravitreal implant) for cytomegalovirus retinitis, Retisert (fluocinolone acetonide intravitreal implant) for non-infectious uveitis, Iluvien (fluocinolone acetonide intravitreal implant) for diabetic macular oedema, and NT-501 (a polymer implant containing human retinal epithelial cells genetically modified to secrete ciliary neurotrophic factor) for non-neovascular (dry) age-related macular degeneration and/or retinitis pigmentosa. Many biodegradable formulations, including different shapes of rods, nail-like plugs, discs, or micro- or nanoparticles, have also been investigated, but are not available as yet for the treatment of vitreoretinal disorders. The most developed biodegradable device, Ozurdex (dexamethasone intravitreal implant), is approved as first-line therapy for the treatment of macular oedema following branch retinal vein occlusion or central retinal vein occlusion. In this article, we review the progress of major biodegradable drug delivery systems currently in clinical trials or in experimental stages for the treatment of vitreoretinal disorders.
authors.affiliation: Research and Development Center, Santen Pharmaceutical Co. Ltd, Ikoma-shi, Nara, Japan. noriyuki.kuno@santen.co.jp
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Kuno
authors.forename: Shinobu
authors.initials: S
authors.lastname: Fujii
mesh_terms: D020341:Absorbable Implants / Q000639:trends; D020533:Angiogenesis Inhibitors / Q000627:therapeutic use; D002986:Clinical Trials as Topic; D003907:Dexamethasone / Q000627:therapeutic use; D003930:Diabetic Retinopathy / Q000378:metabolism*; D004333:Drug Administration Routes; D016503:Drug Delivery Systems; D004847:Epithelial Cells / Q000637:transplantation*; D005446:Fluocinolone Acetonide / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D008268:Macular Degeneration / Q000378:metabolism / Q000628:therapy; D008269:Macular Edema / Q000188:drug therapy / Q000378:metabolism; D012164:Retinal Diseases / Q000378:metabolism / Q000628:therapy*; D012170:Retinal Vein Occlusion / Q000378:metabolism / Q000628:therapy*; D014605:Uveitis / Q000378:metabolism; D014822:Vitreous Body / Q000378:metabolism
chemical_list: D020533:Angiogenesis Inhibitors; D005446:Fluocinolone Acetonide; D003907:Dexamethasone; C035394:fluocinolone