| abstract |
The invention provides a pharmaceutical or veterinary implant, which when parenterally administered releases a pulse of at least one biologically active material at a controllable time interval after implantation. The implant comprises the biologically active material; an excipient comprising at least one water soluble material and at least one water insoluble material; and a polymer film coating adapted to rupture at a predetermined period of time after implantation, and wherein the excipients and polymers are biocompatible. The biologically active material is selected from the. group consisting of antigens, antibodies, hormones, growth promotants, antibiotics, nutrients, minerals and vitamins. Preferably the excipient comprises a combination of two or more water-soluble and water-insoluble materials. |