title: Slow-release drug delivery through Elvax 40W to the rat retina: implications for the treatment of chronic conditions.
abstract: Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.
authors.affiliation: Biotechnology and Applied Clinical Sciences Department, University of L'Aquila.
authors.forename: Lavinia
authors.initials: L
authors.lastname: Fiorani
authors.affiliation: Biotechnology and Applied Clinical Sciences Department, University of L'Aquila.
authors.forename: Rita
authors.initials: R
authors.lastname: Maccarone
authors.affiliation: ARC Centre of Excellence in Vision Science; John Curtin School of Medical Research, Australian National University.
authors.forename: Nilisha
authors.initials: N
authors.lastname: Fernando
authors.affiliation: Biotechnology and Applied Clinical Sciences Department, University of L'Aquila.
authors.forename: Linda
authors.initials: L
authors.lastname: Colecchi
authors.affiliation: Biotechnology and Applied Clinical Sciences Department, University of L'Aquila; ARC Centre of Excellence in Vision Science.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bisti
authors.affiliation: ARC Centre of Excellence in Vision Science; John Curtin School of Medical Research, Australian National University; ANU Medical School, Australian National University; krisztina.valter-kocsi@anu.edu.au.
authors.forename: Krisztina
authors.initials: K
authors.lastname: Valter
mesh_terms: D000613:Aminobutyrates / Q000008:administration & dosage*; D000818:Animals; D003692:Delayed-Action Preparations; D016503:Drug Delivery Systems / Q000379:methods*; D011145:Polyvinyls / Q000008:administration & dosage*; D051381:Rats; D012160:Retina / Q000187:drug effects*
chemical_list: D000613:Aminobutyrates; D003692:Delayed-Action Preparations; D011145:Polyvinyls; C016438:ethylenevinylacetate copolymer; C012729:2-amino-4-phosphonobutyric acid