Implantable therapeutic device

Abstract

A therapeutic device to release a therapeutic agent comprises a porous structure coupled to a container comprising a reservoir. The reservoir comprises a volume sized to release therapeutic amounts of the therapeutic agent for an extended time when coupled to the porous structure and implanted in the patient. The porous structure may comprise a first side coupled to the reservoir and a second side to couple to the patient to release the therapeutic agent. The length of the channels extending from the fist side to the second side may comprise an effective length greater than a distance across the porous structure from the first side to the second side. The therapeutic device may comprise a penetrable barrier to inject therapeutic agent into the device when implanted in the patient.

1 . An ophthalmic drug delivery system comprising:
 an extended release device configured to be implanted in an eye, the device comprising:
 a reservoir formed of a non-permeable material and defining a hollow reservoir volume; and 
 a porous structure coupled to the reservoir, the porous structure having a release rate tuned to release a predetermined rate profile of a drug formulation from the reservoir and into the eye to treat the eye for an extended period of time; and 
   a drug formulation configured to be contained in and delivered by the extended release device, wherein the drug formulation comprises:
 ranibizumab having a concentration in a solution volume and a given half-life upon bolus injection of the solution volume into the eye, 
   wherein the extended release device is tuned to the drug formulation to achieve an effective half-life in the eye when the drug formulation is delivered by the implantable extended release device that is longer than the given half-life in the eye when the drug formulation is delivered by bolus injection.   
     
     
         2 . The system of  claim 1 , wherein the given half-life is within a range from about 1 hour to about 9 days. 
     
     
         3 . The system of  claim 1 , wherein the effective half-life is within a range from about 18 days to about 250 days. 
     
     
         4 . (canceled) 
     
     
         5 . The system of  claim 1 , wherein the reservoir is refillable. 
     
     
         6 . The system of  claim 1 , wherein the reservoir is flushable. 
     
     
         7 . The system of  claim 1 , wherein the target body volume is the vitreous of the eye. 
     
     
         8 . The system of  claim 1 , wherein the effective half-life in the target body volume maintains a concentration of the drug in the target body volume that is above a therapeutic target concentration for a longer period of time than the given half-life maintains the concentration of the drug in the target body volume that is above the therapeutic target concentration. 
     
     
         9 . The system of  claim 1 , wherein the porous structure is coupled to a distal end of the reservoir near an outlet of the reservoir. 
     
     
         10 . The system of  claim 1 , wherein the eye has neovascular (wet) age-related macular degeneration. 
     
     
         11 . The system of  claim 1 , wherein the porous structure has a porosity P between about 3% to about 70% corresponding to the percentage of void spaces extending within the rigid porous structure. 
     
     
         12 . The system of  claim 1 , wherein the reservoir is formed of a rigid material and the reservoir volume is within a range from about 10 uL to about 50 uL. 
     
     
         13 . The system of  claim 1 , wherein the reservoir is formed of a material configured to enlarge between a first narrow profile configuration and a second expanded profile configuration. 
     
     
         14 . The system of  claim 13 , wherein the reservoir volume is within a range from about 10 uL to about 100 uL. 
     
     
         15 . A method of treating an eye using the system of  claim 1 , the method comprising:
 implanting the device into the eye; and   injecting into the reservoir the drug formulation comprising an amount of ranibizumab.   
     
     
         16 . The method of  claim 15 , wherein the amount of ranibizumab is within a range from about 0.1 mg to about 30 mg. 
     
     
         17 . The method of  claim 15 , wherein the drug formulation has a concentration of ranibizumab within a range from about 10 mg/ML to about 600 mg/ML. 
     
     
         18 . A method of extending the half-life of ranzibizumab when injected into the eye using the device of  claim 1 , the method comprising:
 injecting an amount of the drug formulation of  claim 1  into the reservoir of the device when implanted in the eye.   
     
     
         19 . The method of  claim 18 , wherein the given half-life is within a range from about 1 hour to about 9 days. 
     
     
         20 . The method of  claim 18 , wherein the effective half-life is within a range from about 18 days to about 250 days. 
     
     
         21 . The method of  claim 18 , further comprising implanting the device in the eye.