Pharmaceutical preparation in form of coated capsule releasable at lower part of digestive tract

pharmaceutical preparation in the form of a coated capsule which can release contents of a capsule at a lower part of the digestive tract comprising

• (a) a hard capsule containing at least an acidic substance to control release of the contents of the capsule,
• (b) a polymer film soluble at low pH which is formed of a surface of said hard capsule,
• (c) an enteric coating film which is formed on a surface of said polymer film soluble at low pH, and
• (d) at least one of
• (1) a sealing means provided around a joint of a body and a cap of said hard capsule, and
• (2) an intermediate layer comprising at least one member selected from the group consisting of a medicament and a water-soluble substance between said polymer film soluble at low pH and said enteric coating film.

A pharmaceutical preparation in the form of a coated capsule which can release contents of a capsule in a lower part of the digestive tract, consisting essentially of:

• (a) a core in the form of a hard capsule containing an active agent and a solid acidic substance, and having an outer surface,
• (b) a polymer film soluble at low pH which is formed on said outer surface of said hard capsule,
• (c) optionally an intermediate layer selected from the group consisting of at least one of a medicament and a water-soluble substance formed on an outer surface of said polymer film soluble at low pH, and
• (d) an enteric coating film which is formed on an outer surface of said intermediate layer if present or on an outer surface of said polymer film soluble at low pH if said intermediate film is not present.

A pharmaceutical preparation in the form of a coated capsule which can release contents of a capsule at a lower part of the digestive tract comprising

• (a) a hard capsule containing at least an acidic substance to control release of the contents of the capsule,
• (b) a polymer film soluble at low pH which is formed on a surface of said hard capsule, and
• (c) an enteric coating film which is formed on a surface of said polymer film soluble at low pH, and wherein
• (1) said acidic substance is at least one member selected from the group consisting of an organic acid and an inorganic acid,
• (2) said polymer film soluble at low pH comprises at least one member selected from the group consisting of polyvinyl acetal diethylaminoacetate, methyl methacrylate-butyl methacrylate-dimethylaminoethyl methacrylate copolymer and polyvinyl aminoacetal, or
• (3) both (1) or (2).