Osmotic drug delivery system
US4475916A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 18, 1982 |
| Grant date | Oct 9, 1984 |
| Priority date | — |
| Expiry date | Mar 18, 2002 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K9/0004
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
An osmotic drug (or other beneficial substance) delivery system comprises a compartment with one or more chambers in series formed by an external shell and chamber-dividing walls of a microporous material and successive overlayers of semipermeable membranes completely covering the outer shell of all but one chamber and substantially covering the outer shell of that one chamber, each successive overlayer completely covering all but one more chamber and substantially covering that one more chamber. Osmotic agents, adjuvants, enzymes, drugs, pro-drugs, pesticides and the like are incorporated in the chambers covered by the semipermeable membranes, and external fluids that diffuse into that chamber form solutions and by osmotic pressure are forced through the microporous chamber-dividing wall to the drug or drug-forming chamber to form a solution thereof and then through the exposed microporous shell to the exterior of the device at a rate controlled by the permeability of the semipermeable overlay and the osmotic pressure gradient across the shell.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.