Process for the preparation of a hot-melt extruded laminate

Abstract

A process for the preparation of a bioadhesive laminate comprising a hot-melt extruded reservoir layer and a hot-melt extruded backing layer is provided. The reservoir layer comprises a thermoplastic bioadhesive composition containing an active agent. An active agent-containing thermoplastic bioadhesive hydrophilic composition is hot-melt coextruded with a hydrophobic composition to form at least a bi-layered laminate. The hydrophilic composition and the hydrophobic composition have at least one polymer in common. In addition, the melt flow index of the hydrophobic composition is within 50% of the melt flow index of the hydrophilic composition. As a result, the laminate has a uniform transverse cross-section and/or a uniform longitudinal cross-section throughout a major of the length of the laminate. Moreover, when the laminate is divided into unit doses of approximately the same size, they have a high degree of content uniformity with respect to the active agent(s) present therein.

What is claimed is: 
     
         1 ) A bioadhesive bi-layered hot-melt extruded laminate comprising a hydrophilic bioadhesive reservoir layer and a hydrophobic backing layer, wherein a) the bioadhesive reservoir layer comprises an active agent;
 b) each of the bioadhesive reservoir layer and the backing layer comprises poly(ethylene) oxide (PEO); and   c) the backing layer comprises a hydrophilic polymer in a sufficiently low amount such that the backing layer is hydrophobic.   
     
     
         2 ) The laminate of  claim 1 , wherein the reservoir layer comprises two or more water swellable, water soluble or water erodible thermoplastic bioadhesive polymers. 
     
     
         3 ) The laminate of  claim 1 , wherein the backing layer comprises two or more hydrophobic polymers. 
     
     
         4 ) The laminate of  claim 1 , wherein the melt flow index of the reservoir layer is within 50% of the melt flow index of the backing layer. 
     
     
         5 ) The laminate of  claim 1 , wherein the PEO in each layer is selected from the group consisting of PEO Grade 1, PEO Grade 2, PEO Grade 3, and a combination thereof, wherein: PEO Grade 1 is polyethylene oxide with (i) a solution viscosity in the range of 12-8800 mPa·s at 25° C. in a 5% solution or (ii) an approximate molecular weight range from 100,000-600,000; PEO Grade 2 is polyethylene oxide with (i) a solution viscosity in the range of 8800 mPa·S at 25° C. in a 5% solution to 4000 mPa·s at 25° C. in a 2% solution or (ii) an approximate molecular weight range from 900,000-2,000,000; and PEO Grade 3 is polyethylene oxide with (i) a solution viscosity in the range of 1650-15,000 mPa·s at 25° C. in a 1% solution or (ii) an approximate molecular weight range from 4,000,000-8,000,000. 
     
     
         6 ) The laminate of  claim 1 , wherein the laminate comprises a controlled, sustained, slow, extended, or targeted release therapeutic composition. 
     
     
         7 ) The laminate of  claim 1 , wherein the laminate comprises a dosage form adapted for transdermal, transmucosal, rectal, pulmonary, nasal, vaginal, ocular, or otic drug delivery, or as an implantable drug delivery device. 
     
     
         8 ) The laminate of  claim 1 , wherein the active agent is selected from the group
 consisting of testosterone, oxybutynin, morphine, fentanyl, aspirin, lansoprazole, omeprazole, pantoprazole, rabeprazole and naltrexone.   
     
     
         9 ) The laminate of  claim 1 , wherein each of the backing layer and the reservoir layer comprises at least 10% wt. of the PEO. 
     
     
         10 ) The laminate of  claim 1  further comprising a release liner layer removably affixed to the reservoir layer. 
     
     
         11 ) The laminate of  claim 1 , wherein the reservoir layer comprises 40 to 90% by wt. of the laminate. 
     
     
         12 ) A unit dose comprising a portion of a laminate according to  claim 1 , wherein the
 reservoir layer has an average exposed surface area between 90 and 250 mm 2 .   
     
     
         13 ) The unit dose of  claim 12  comprising a surface area to dose ratio of 5 to 35 mm 2 /mg active agent based upon the exposed surface of the reservoir layer. 
     
     
         14 ) The laminate of  claim 1 , wherein the active agent is fentanyl. 
     
     
         15 ) The laminate of  claim 1 , wherein the active agent is testosterone. 
     
     
         16 ) The laminate of  claim 1 , wherein the bioadhesive reservoir layer further comprises an acidic component. 
     
     
         17 ) The laminate of  claim 5 , wherein the PEO in the bioadhesive reservoir layer comprises two or more grades of PEO selected from the group consisting of PEO Grade 1, PEO Grade 2, and PEO Grade 3. 
     
     
         18 ) The laminate of  claim 5 , wherein both the PEO in the bioadhesive reservoir layer and the PEO in the backing layer comprise two or more grades of PEO selected from the group consisting of PEO Grade 1, PEO Grade 2, and PEO Grade 3. 
     
     
         19 ) The laminate of  claim 1 , wherein the reservoir layer comprises about 10% to about 70% wt. of the PEO.