Block copolymer matrix for transdermal drug release
US4840796A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 22, 1988 |
| Grant date | Jun 20, 1989 |
| Priority date | — |
| Expiry date | Apr 22, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/61
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
A transdermal drug delivery system, is provided which includes, in combination, an impermeable backing member, a matrix containing a medicinally active ingredient, and a pressure sensitive adhesive for affixing the system to the skin of a patient; the improvement in such system is based on the fact that said matrix is drug permeable (including to hydrophilic drugs) and is formed of a copolymer which can be softened sufficiently at temperature between 45.degree. C. and 160.degree. C. to incorporate the drugs therein without damage caused by heat or chemical reactions, the matrix being formed of a substantially linear block copolymer which is a reaction product of a polydiorganosiloxane which forms "soft" segments in said reaction product and a diisocyanate which forms "hard" segments, said copolymer having a glass transition temperature between 45.degree. C. and 160.degree. C. said soft segments comprising from 80 to 99 percent by weight, based on the weight of said copolymer, the average molecular weight of the copolymer being between 15,000 and 500,000.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.