COMPOSICIONES FARMACEUTICAS DE LIBERACION CONTROLADA Y PROCESO PARA SU PREPARACION

This invention relates to a controlled release pharmaceutical composition comprising: (a) an outer layer comprising a pH independent hydrophilic polymer together with one or more fillers; and (b) one or more inner layers each comprising an active ingredient; wherein the outer layer is gradually removed by a combination of dissolution and erosion following administration and the inner layer or layers is gradually removed by a combination of dissolution and erosion or disintegrates rapidly once exposed; and processes for the preparation thereof. In particular the invention relates to pharmaceutical compositions for the controlled release of H2-antagonists or serotonin agonists or antagonists.