Porous microspheres for drug delivery and methods for making same

Patent 4818542 Issued on April 4, 1989. Estimated Expiration Date:

April 4, 2006. 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.

Abstract Claims Description Full Text

Patent References

3460972

3737337

Preparation of microcapsules
Patent #: 3943063
Issued on: 03/09/1976
Inventor: Morishita , et al.

Process for preparation of microspheres Patent #: 4384975
Issued on: 05/24/1983
Inventor: Fong

Inventors

Assignee

The University of Kentucky Research Foundation

Application

No. 06/846513 filed on 03/31/1986

US Classes:

424/491, Containing proteins and derivatives264/4.6, Solid-walled microcapsule formed by physically removing a constituent (e.g., evaporation, extraction, etc.)34/287, Including vacuum424/486, Synthetic polymer424/492, Gelatin424/497, Containing solid synthetic polymers424/499, Contains proteins or derivative or polysaccharides or derivative424/501, Contains solid synthetic resin427/213.3, Solid encapsulation process utilizing an emulsion or dispersion to form a solid-walled microcapsule (includes liposome)427/213.31, With post-treatment of encapsulant or encapsulating material (e.g., further coating, hardening, etc.)427/213.35, Solid-walled microcapsule formed from gelatin or derivative thereof427/213.36, Solid-walled microcapsule formed from preformed synthetic polymer428/402.24, Microcapsule with solid core (includes liposome)514/965Discrete particles in supporting matrix

Examiners

Primary: Lovering, Richard D.

Attorney, Agent or Firm

Burns, Doane, Swecker & Mathis

International Class

A61K 9/16 (20060101)

Abstract

Controlled release drug delivery systems comprised of spherical microporous polymeric network of interconnecting channels containing pore incorporated drugs or other agents wherein the drugs or agents are confined within the pore channel are described. Also disclosed are processing parameters in connection with the novel method of the invention for obtaining drug delivery systems especially suited for parenteral as well as oral administration.

Other References

Beck et al.: "A New Long-Acting Injectable Microcapsule System . . . ", Fertility and Sterility, vol. 31, No. 5, May 1979, pp. 545-551
Fong et al.: "Evaluation of Biodegradable Microspheres Prepared by a Solvent Evaporation Process . . . ", J. of Controlled Release, 3 (1986) 119-130