Compositions with controlled zero-order delivery rate and method of preparing these compositions

摘要

The present invention relates to compositions having a controlled zero-order delivery rate of the active component. The composition comprises a core or a protective layer coated with a continuous matrix of constant composition containing such a mixture of active substance(s) and excipient(s) that the concentration of the active substance(s) decreases from the core or the protective layer towards the outside, and the concentration of the excipient(s) increases in the same direction, whereas the sum of two substantially remains constant over the whole distance.