Ocular implant made by a double extrusion process
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.
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 .