Sustained-release preparation and production thereof
Patent 4894239 Issued on January 16, 1990. Estimated Expiration Date: 
May 16, 2008. 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.
May 16, 2008. 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 References 2990332 3138525 3313686 3499960 3594470 3904444 Method for making a microsealed delivery device Prolonged release pharmaceutical preparations Crosslinked, porous polymers for controlled drug delivery Sustained-release formulation containing and amino acid polymer InventorsAssigneeApplicationNo. 194210 filed on 05/16/1988US Classes:424/497, Containing solid synthetic polymers424/469, Discrete particles in supporting matrix424/489, Particulate form (e.g., powders, granules, beads, microcapsules, and pellets)424/490, Coated (e.g., microcapsules)424/494, Cellulose derivatives424/495, Ethyl cellulose424/496Containing natural gums/resinsExaminersPrimary: Page, Thurman K.Attorney, Agent or FirmForeign Patent References
International ClassA61K 009/16Foreign Application Priority Data1987-06-02 JPAbstractThe present invention concerns a sustained-release microcapsule preparation comprising an ion exchange resin with 6 to 16% crosslinking, containing a drug adsorbed in an amount not less than 80% of its theoretical ion adsorption amount and coated with a water-permeable polymer. | |
