A novel matrix composition for pharmaceutical use. The matrix composition has been designed so that it is especially suitable in those situation where an improved bioavailability is desired and/or in those situation where a slightly or insoluble active substance is employed. Accordingly, a controlled release pharmaceutical composition for oral use is provided in the form of a coated matrix composition, the matrix composition comprising i) a mixture of a first and a second polymer that have plasticizing properties and which have melting points or melting intervals of a temperature of at the most 200°C, the first polymer being selected from the group consisting of polyethylene glycols and polyethylene oxides, and the second polymer being selected form block copolymer of ethylene oxide and propylene oxide including poly(ethylene-glycol-b-(DL-lactic acid-co-glycolic acid) - b-ethylene glycol (PEG-PLGA PEG), poly((DL-lactic acid-co-glycolic acid) - g-ethylene glycol) (PLGA-g-PEG), poloxamers and polyethylene oxide - polypropylene oxide (PEO-PPO), ii) a therapeutically, prophylactically and/or diagnostically active substance, the matrix composition being provided with a coating having at least one opening exposing at one surface of said matrix, wherein the active substance is released with a substantially zero order release.Linvention porte sur une nouvelle composition matricielle destinée à un usage pharmaceutique. La composition matricielle a été conçue de façon à être appropriée notamment dans les situations où lon souhaite obtenir une meilleure biodisponibilité et/ou dans celles où lon veut utiliser une substance active légère ou insoluble. En conséquence, on a décidé de produire une composition pharmaceutique à libération contrôlée, à usage oral, se présentant sous la forme dune composition matricielle enrobée comprenant : i) un mélange dun premier et dun second polymère ayant des propriétés plastifiantes et dont les points de fusion ou intervalles de fusion de la te
