Controlled release growth hormone containing microspheres

摘要

Growth hormone polymeric controlled release systems are described wherein the growth hormone retains good biological activity and is released over an extended period of time following administration by injection. In the preferred embodiment, human growth hormone polymeric microspheres are made using very cold temperatures to freeze the polymer-growth hormone mixtures into polymeric microspheres with very high retention of biological activity and material. Sustained release of biologically active growth hormone is achieved when the microspheres are tested in vivo, extending over a period of greater than one day to several months. Altered release can be achieved by inclusion of degradation modifiers, pore forming agents, and stabilizers of the growth hormone.