Abstract:
An injection formulation of a drug is provided to release a desired amount of the drug gradually for a desired time to a portion desired by a drug person administered to the drug by using a bio-compatible and thermosensitive polyethyleneglycol/polyester block copolymer to make the drug semi-solid or gel. An injection formulation comprises a hydrophilic portion consisting of polyethyleneglycol having a molecular weight of 350-2,000g/mole and a biodegradable polyester hydrophobic portion containing a caprolactone(CL) segment as an essential ingredient and at least one of a paradioxanone(PDO) segment and a trimethylene carbonate(TMC) segment and is characterized in that it is prepared by mixing a protein or peptide-based drug with a bio-compatible and thermosensitive polyethyleneglycol/biodegradable polyester block copolymer having a molecular weight of 2,000-7,000g/mole, wherein the protein or peptide-based drug is albumin, calcitonin, octreotide, leuprolide, adenosine deaminase, L-asparaginase, urokinase, interferon alpha-2b, interferon beta-1b, human insulin, insulin-like growth factor-1(IGF-1), erythropoietin(EPO), granulocyte colony stimulating factor(G-CSF), human growth hormone(hGH), nerve growth factor(NGF), brain-derived neurotrophic factor(BDNF), neurotrophin-3(NT-3), fibroblast growth factor(FGF), epidermal growth factor(EGF), endothelial growth factor(VEGF), transforming growth factor-beta(TGF-beta) or platelet-derived growth factor(PDGF).