3854480 is referenced by 319 patents and cites 8 patents.

Drug-delivery system for releasing drug at a controlled rate for a prolonged period of time is formed from a solid inner matrix material having solid particles of drug dispersed therethrough. Surrounding the inner matrix is an outer polymeric membrane, insoluble in body fluids. Both the inner matrix material and the outer polymeric membrane are permeable to passage of the drug by diffusion but the drug diffuses through the outer polymeric membrane at a lesser rate so that passage through the polymeric membrane is the drug release rate controlling step.

Drug-delivery system
Application Number
Publication Number
Application Date
June 2, 1970
Publication Date
December 17, 1974
Zaffaroni Alejandro
Sabatine Paul L
Ciotti Thomas E
Mandell Edward L
Alza Corporation
A61m 05/00
A61M 31/00
A61M 37/00
A61F 09/00
A61L 15/58
A61L 15/16
A61K 09/70
A61K 09/00
A61D 07/00
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