Particle-based multi-layer therapeutic delivery device and method

A device for delivery of a first therapeutic agent and a second therapeutic agent to a site in epithelial tissue, the device comprising:

• a first layer comprising:
• a first porous, mucoadhesive, freeze-dried polymeric matrix having first and second opposed surfaces, the first matrix formed by a composition comprising chitosan, a hydration promoter, a particle adhesion inhibitor, and a particle aggregation inhibitor, and
• a plurality of first particles embedded within the first matrix so as to be directly surrounded by, and in contact with, the first matrix, the first particles containing the first therapeutic agent and having a coating around the first therapeutic agent, the coating comprising chitosan so as to provide controlled release of the first therapeutic agent from the first particles through one of the opposed surfaces of the first matrix;
• and
• a second layer, adjacent to the first layer, the second layer comprising:
• a second, freeze-dried polymeric matrix having third and fourth opposed surfaces, the second matrix containing the second therapeutic agent,
• wherein a member selected from the group consisting of the first layer, the second layer, and a combination of the first layer and the second layer, is configured to be attached to the site in the epithelial tissue.