Details for Patent: 8,778,381

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:	Mar 12, 2013
Application Number:	13/797,230
Claims:	1. A method for making a bioerodible implant for treating a medical condition of the eye, the method comprising: a) milling a hydrophilic ended poly(D,L-lactide-co-glycolide) (PLGA) copolymer; b) milling a hydrophobic ended poly(D,L-lactide-co-glycolide) (PLGA) copolymer; c) blending the milled polymers together with particles of a steroidal anti-inflammatory agent to form a blended mixture comprising hydrophilic ended PLGA, hydrophobic ended PLGA, and a steroidal anti-inflammatory agent, wherein at least about 75% of the particles of the steroidal anti-inflammatory agent have a diameter of less than about 20 .mu.m; d) carrying out a first extrusion of the blended mixture to thereby obtain a first extrusion product; e) pelletizing the first extrusion product; and f) carrying out a second extrusion of the pelletized first extrusion product, thereby obtaining a bioerodible implant for treating a medical condition of the eye; wherein the implant has a total weight ranging from about 100-5000 .mu.g. 2. The method of claim 1, wherein the steroidal anti-inflammatory agent is dexamethasone, fluocinolone, hydrocortisone, methylprednisolone, prednisolone, prednisone, or triamcinolone. 3. The method of claim 2, wherein the hydrophilic ended PLGA and hydrophobic ended PLGA together constitute about 20 to about 90 weight percent of the bioerodible implant. 4. The method of claim 3, wherein the ratio of lactic to glycolic acid monomers in the hydrophilic ended PLGA and in the hydrophobic ended PLGA is about 50/50 weight percentage. 5. The method of claim 4, wherein the ratio of hydrophilic end PLGA to hydrophobic end PLGA in the blended mixture is 3:1 by weight.