The present invention relates to a drug carrier composition comprising i) one or more biodegradable hydrating ceramics ii) one or more expandable agents, and iii) sorbed aqueous medium which in solid form has a ruptured structure. The function of the expandable agent is to create a ruptured structure in the solidified composition, either a foam-like structure or a disintegrated structure where it is split into a large number of parts, particles, units, granules or pieces, so as to obtain an enlarged apparent surface area that is exposed to degradation or erosion upon administration. Suitable substances to obtain this surface enlarging effect are gas-forming agents or swelling agents, gelling agents or disintegrants, here referred to as expandable agents. The expandable agents may be bioresorbable or non-bioresorbable.