Process for the preparation of a hot-melt extruded laminate

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,
• 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,
• wherein the PEO in the bioadhesive reservoir layer comprises PEO Grade 1, PEO Grade 2, and PEO Grade 3.