| abstract |
The present invention relates to a controlled release agent having antiprogestin properties over a prolonged period of time, said agent comprising a drug-containing core or a membrane surrounding said core, wherein the core and membrane are made of a siloxane-based elastomer composition comprising at least one elastomer and optionally uncrosslinked polymer. The compositions are characterized in that the elastomeric composition comprises poly (alkylene oxide) groups and that the poly (alkylene oxide) groups are present in the elastomer or polymer in the form of alkoxy-terminated grafts of polysiloxane units, or as blocks, said bolts or blocks attached. to polysiloxane units by carbon-silicon bonding or as a mixture of these forms. The composition may be in the form of an implant, an intra-lintel intracervical or intravaginal device, or a transdermal patch. |