Abstract: A swellable intermediate layer that includes a swellable material selected from the group of starch, starch derivatives such as pregelatinised starch, sodium carboxyethyl starch, sodium starch gycolate, cellulose, cellulose ethers such as HPMC, HPC, HEC MC, sodium carboxymethyl cellulose, carrageenans, aginates, pectins, xanthanes and their derivatives, guar gum, tragacanth, polyvinyl pyrrolidones and mixtures thereof, in a delayed-release, solid pharmaceutical formulation for peroral use. The formulation has a substrate containing an active substance, the swellable intermediate layer and a retarding coating layer for the adjustment of a release profile for the active substance which essentially permits complete release near the end.