Abstract: A drug delivery device for the controlled release of a therapeutically active ingredient into an environment of use is disclosed which comprises:(A) a core composition comprising(a) a plurality of controlled release solubility modulating units comprising solubility modulating agents each of which is a complexing agent or a surfactant and which is either (i) surround by a water insoluble cost containing at least one pore forming additive dispersed throughout said coat, or (ii) dispersed in an individual matrix substrate, and(b) A therapeutically active ingredient; and(B) a water insoluble microporous wall surrounding said core composition comprising:(i) a polymer material that is permeable to water but substantially impermeable to solute and(ii) 0.1 to 75% by weight, based on the total weight of (i) and (ii), of at least one water leachable pore forming additive dispersed throughout said wall.

Abstract: The instant invention is directed to a multiparticulate osmotic pump, for the controlled release of a pharmaceutically active agent to an environment of use, said pump comprising:(I) a carrier medium which does not maintain its integrity in the environment of use;(II) a multiple of tiny osmotic pump elements each consisting essentially of:(A) a core comprises at least one pharmacologically active agent soluble in an external fluid, or a mixture of an agent having a limited solubility in the external fluid with an osmotically effective solute that is soluble in the fluid, which exhibit an osmotic pressure gradient across the wall against the external fluid surrounded by(B) a rate controlling water insoluble wall, having a fluid permeability of 6.96.times.10.sup.-18 to 6.96.times.10.sup.14 cm.sup.3 sec/g and a reflection coefficient of less than 0.5, prepared from:(i) a polymer permeable to water but impermeable to solute and(ii) 0.

Abstract: The instant invention is directed to a drug delivery device for the controlled release of beneficial agents and drugs into an environment of use comprising:(A) a core composition comprising(a) a water insoluble, non-diffusible charged resin entity, and(b) a diffusible, water soluble ionizable therapeutically active ingredient carrying the same charge as said resin entity; and(B) a substantially imperforate water-insoluble wall surrounding said core composition, prepared from a semipermeable material substantially impermeable to the core composition and permeable to the passage of an external fluid in the environment of use, with said wall having a hole(s) for release of the therapeutic agent through the water insoluble wall.

Abstract: A device is disclosed for the controlled delivery of a beneficial agent. The agent is delivered to the environment surrounding the device at a substantially constant rate for a specified period with a reduced dependence on the environmental pH. The device is comprised of a core compartment containing (1) a charged, water insoluble, non-diffusible component and (2) at least one diffusable water soluble ionizable beneficial agent. The core is surrounded by a water insoluble wall containing leachable pore forming additive(s) dispersed throughout said wall, with said wall impermeable to core components (1) and permeable to beneficial agent(s) (2). In operation the insoluble charged component (often polymeric resins) and water soluble ionizable beneficial agent have the same electro-static charge and do not form an ion exchange complex.

Abstract: The invention relates to the use of carboxylic acids incorporated as a catalyst in poly(orthoester)s and other acid labile polymers such that upon exposure to aqueous environments the acid catalyzes the erosion of the polymer matrix. The rate of release of a drug substance incorporated into or surrounded by the poly(orthoester) or other acid labile polymer can be controlled in that the drug is released as the polymer is eroded in response to the catalytic action of the acid incorporated therein.