Diffusion-osmotic controlled drug-release pharmaceutical composition and

Abstract

The invention relates to a novel diffusion-osmotic controlled drug-release pharmaceutical composition containing a one-layer tablet core including a polymeric film-coat, a therapeutically active agent and a hydrophilic polymer; if desired, a two-layer tablet core including active agent and hydrophilic polymer in the first layer thereof and a hydrophilic polymer in the second layer thereof; at least one bore on the part of film-coat in contact with the core or core layer containing the active agent; and, if desired, containing one or more bore(s) in the part thereof in contact with the second layer containing the hydrophilic polymer, which comprises an ammonium methacrylate copolymer as coating material and hydroxypropyl-methylcellulose as hydrophilic polymer. The composition according to the invention is useful for preparing controlled drug-release tablets containing as active agents e.g. .beta.-adrenergic inhibitors (e.g. propranolol) calcium-antagonists (e.g. nifedipine), angiotensin convertase enzyme (ACE) inhibitors (e.g. captopril); prazosin; or nitroglycerol, all used in heart and circulation diseases; vasodilatory active agents (e.g. pentoxyfylline), nonsteroidal antiinflammatory agents (e.g. naproxene), analgetic drugs (e.g. morphine) and drugs acting on the central nervous system (e.g. amitriptyline, buspiron). The invention furthermore relates to a process for the preparation of the above compositions.