Patent ID: 6893662

Claim:
A pharmaceutical composition in a solid unit dosage form for oral administration in a human or lower animal consisting essentially of: a. a safe and effective amount of a therapeutically active agent; b. an inner coating layer selected from the group consisting of poly(methiacrylic acid, methyl methacrylate) 1:2, poly(methacrylic acid, methyl methacrylate) 1:1, and mixtures thereof; and c. an outer coating layer, applied to the inner coating layer, said outer coating layer comprising an enteric polymer that begins to dissolve in an aqueous medium at a pH of less than about 7, said enteric polymer being selected from the group consisting of polymethacrylates, anionic polymethacrylates, poly(methacrylic acid, methyl methacrylate) 1:1, mixtures of poly(methacrylic acid, methyl methacrylate) 1:2 and poly(methacrylic acid, methyl methacrylate) 1;1, polyvinyl acetate phthalate, poly(methacrylic acid, ethyl acrylate) 1:1, and compatible mixtures thereof; wherein the inner coating layer is not the same as the outer coating layer; wherein if the inner coating layer is poly(methacrylic acid, methyl methacrylate) 1:1 then the outer coating layer is not poly(methacrylic acid, methyl methacrylate) 1:2 or is not a mixture of poly(methacrylic acid, methyl methacrylate) 1:1 and poly(methacrylic acid, methyl methacrylate) 1:2; and wherein the inner coating layer and the outer coating layer contain no therapeutically active agent.