Osmotic devices having composite walls
Patent 4077407 Issued on March 7, 1978. Estimated Expiration Date: 
March 7, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
March 7, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesInventorsApplicationNo. 05/634859 filed on 11/24/1975US Classes:424/427, Ocular106/168.01, Cellulose ester or salt thereof106/171.1, Cellulose acetate210/500.28, Cyclic264/49, By treating occluded solids424/431, Tampon424/436, Anal, rectal (e.g., suppositories, etc.)424/449, Transdermal or percutaneous424/473, With porous, perforated, apertured, or sieved layer (e.g., dialyzing layer, microporous layer, etc.)604/11MEANS FOR INSERTING FIBROUS OR FORAMINOUS RESIDENT PACKING, RECEPTOR, OR MEDICAMENT CARRIER INTO BODY ORIFICEExaminersPrimary: Pellegrino, Stephen C.Assistant: Gron, Teddy S. Attorney, Agent or FirmInternational ClassA61K 9/00 (20060101)AbstractAn osmotic device for delivering an active agent is disclosed. The device is comprised of a wall surrounding a compartment and has a passageway through the wall for releasing the agent. The wall is formed of a multiplicity of materials comprising a material permeable to an external fluid and substantially impermeable to agent and at least one additional material selected from a material that imparts stability to the wall, enhances the permeability of the wall to fluids, or aids in forming the wall. The compartment comprises an active agent that exhibits an osmotic pressure gradient against an external fluid, or the agent is mixed with an osmotically effective compound that exhibits an osmotic pressure gradient against the fluid. Agent is released from the device by fluid being imbibed through the wall into the compartment at a rate controlled by the permeability of the wall and the osmotic pressure gradient across the wall, to produce a solution containing agent that is released through the passageway at a controlled and continuous rate over a prolonged period of time. | |
