Biodegradable drug delivery compositions

Abstract

A biodegradable drug delivery compositions comprising a triblock copolymer containing a polyester and a polyethylene glycol and a diblock copolymer containing a polyester and an end-capped polyethylene glycol, as well as a pharmaceutically active principle is disclosed.

What is claimed is: 
     
         1 . A syringe comprising a biodegradable drug delivery composition comprising
 (a) a biodegradable triblock copolymer having the formula: poly(lactic acid) v -poly(ethylene glycol) w -poly(lactic acid) x , wherein v and x are the number of repeat units ranging from 24 to 682 and w is the number of repeat units ranging from 4 to 273 and v=x or v≠x;   (b) a biodegradable diblock copolymer having the formula: methoxy poly(ethylene glycol) y -poly(lactic acid) z , wherein y and z are the number of repeat units, with y ranging from 3 to 45 and z ranging from 7 to 327, wherein the ratio of the biodegradable triblock copolymer of (a) and the biodegradable diblock copolymer of (b) is 1:3 to 1:8 or 1:1 to 1:19 or 3:2 to 1:19 in said biodegradable drug composition, which is insoluble in an aqueous environment; and   (c) risperidone.   
     
     
         2 . The syringe according to  claim 1 , wherein the biodegradable drug delivery composition delivers the risperidone for at least 7 days when administered to a patient. 
     
     
         3 . The syringe according to  claim 1 , wherein the biodegradable drug delivery composition delivers the risperidone for at least 30 days when administered to a patient. 
     
     
         4 . A method of administering risperidone to a patient in need thereof which comprises injecting said patient using the syringe according to  claim 1  to the biodegradable drug delivery composition containing risperidone. 
     
     
         5 . A method of treating a condition which is responsive to risperidone which comprises administering to a patient in need thereof a biodegradable drug delivery composition with the drug implant according  claim 7 . 
     
     
         6 . The method according to  claim 5 , wherein said drug implant is administered using a syringe. 
     
     
         7 . A drug implant comprising
 (a) a biodegradable triblock copolymer having the formula: poly(lactic acid) v -poly(ethylene glycol) w -poly(lactic acid) x , wherein v and x are the number of repeat units ranging from 24 to 682 and w is the number of repeat units ranging from 4 to 273 and v=x or v≠x;   (b) a biodegradable diblock copolymer having the formula: methoxy poly(ethylene glycol) y -poly(lactic acid) z , wherein y and z are the number of repeat units, with y ranging from 3 to 45 and z ranging from 7 to 327, wherein the ratio of the biodegradable triblock copolymer of (a) and the biodegradable diblock copolymer of (b) is 1:3 to 1:8 or 1:1 to 1:19 or 3:2 to 1:19; and   (c) risperidone.   
     
     
         8 . The syringe according to  claim 1 , further comprising an organic solvent.