Details for Patent: 8,048,445

Title:	Ocular implant made by a double extrusion process
Abstract:	The invention provides biodegradable implants sized for implantation in an ocular region and methods for treating medical conditions of the eye. The implants are formed from a mixture of hydrophilic end and hydrophobic end PLGA, and deliver active agents into an ocular region without a high burst release.
Inventor(s):	Shiah; Jane-Guo (Irvine, CA), Bhagat; Rahul (Irvine, CA), Blanda; Wendy M. (Tustin, CA), Nivaggioli; Thierry (Atherton, CA), Peng; Lin (South San Francisco, CA), Chou; David (Palo Alto, CA), Weber; David A. (Danville, CA)
Assignee:	Allergan, Inc. (Irvine, CA)
Filing Date:	Jul 15, 2008
Application Number:	12/173,746
Claims:	1. A method for making an ocular bioerodible implant for treating a condition of the eye, the method comprising performing a plurality of heat extrusions of a biodegradable polymer and at least one corticosteroid thereby forming a filament including a homogeneous distribution of the at least one corticosteroid, wherein the ocular bioerodible implant has a reduced in-batch variability relative to a single extrusion implant. 2. The method of claim 1 further comprising the step of milling the biodegradable polymer prior to a first extrusion. 3. The method of claim 1, wherein the biodegradable polymer comprises poly(lactic-co-glycolic)acid (PLGA) copolymer. 4. The method of claim 3 wherein the ratio of lactic to glycolic acid monomers is about 50/50 weight percentage. 5. The method of claim 3 wherein the PLGA copolymer is about 20 to about 90 weight percent of the bioerodible implant. 6. The method of claim 5 wherein the PLGA copolymer is about 40 percent by weight of the bioerodible implant. 7. A method for making a bioerodible implant for treating an ocular condition, the method comprising the steps of: (a) milling a biodegradable polymer; (b) blending the milled biodegradable polymer and particles of an active agent, to thereby obtain a blended mixture of the milled biodegradable polymer and the particles of the active agent, wherein at least about 75% of the particles of the active agent have a diameter of less than about 201 Jm; (c) carrying out a first heat extrusion of the blended mixture, to thereby obtain a first extrusion product; (d) pelletizing the first heat extrusion product, and; (e) carrying out a second heat extrusion of the pelletized first extrusion product, thereby obtaining a bioerodible implant for an ocular condition including a homogeneous distribution of the active agent, wherein the bioerodible implant has a reduced in-batch variability relative to a single extrusion implant. 8. A bioerodible implant for treating an ocular condition made by the method of claim 1.