Dosage form with a core tablet of active ingredient sheathed in a compressed annular body of powder or granular material, and process and tooling for producing it

A solid pharmaceutical dosage form for oral administration to a patient, comprising:

• a recessed core tablet having a substantially exposed first surface and a substantially exposed second surface and an outer surface extending between the exposed first and second opposed surfaces, wherein the first and second substantially exposed surfaces are opposed one to the other, and the substantially exposed surfaces are exposed to the dosage form external environment;
• the core tablet containing an active pharmaceutical ingredient;
• wherein
• the core tablet is sheathed in an annular body of compressed powder or compressed granular material that encircles the core tablet, and is in contact with the outer surface of the core tablet, leaving the opposed surfaces of the core tablet substantially exposed;
• the annular body having opposed first and second annular faces, an outer surface extending between the annular faces outer edges, and an inner surface extending between the annular faces inner edges, thereby defining an annulus;
• and wherein
• the substantially exposed first and second opposed surfaces of the core tablet are both recessed with respect to the annular faces of the annular body, such that, prior to and following oral administration, the recessed surfaces of the core tablet are shielded from contact with the mucosa lining the gastrointestinal tract.