The present invention discloses stable pharmaceutical preparation and drug delivery device.In certain embodiments, the drug delivery device accommodates Reservoir Body, and the Reservoir Body is contacted when being implanted in patients body with organizational environment part.The Reservoir Body is kept in contact via the porous structure in the shell of the delivery apparatus with the environment.The Reservoir Body accommodates therapeutic biomolecule and dimolecular combination, and second molecule is used to make the therapeutic biomolecule stable and limits the solubility of the therapeutic biomolecule, thus controls the amount of therapeutic biomolecule dissolving.The concentration of the solubility therapeutic biomolecule or the size of the surface area of the porous structure control the rate that the therapeutic biomolecule is delivered to target tissue.
