Patent ID: 6340742
Filing Date: 2002-01-22
Classification: A61K,A61P,C07K

Abstract:
A conjugate, said conjugate comprising an erythropoietin glycoprotein having at least one free amino group and having the in vivo biological activity of causing bone marrow cells to increase production of reticulocytes and red blood cells and selected from the group consisting of human erythropoietin and analogs thereof which have the primary structure of human erythropoietin modified by the addition of from 1 to 6 glycosylation sites or by the rearrangement of at least one glycosylation site; said glycoprotein being covalently linked to from one to three lower-alkoxy poly(ethylene glycol) groups, each poly(ethylene glycol) group being covalently linked to the glycoprotein via a linker of the formula â€”C(O)â€”Xâ€”Sâ€”Yâ€” with the C(O) of the linker forming an amide bond with one of said amino groups, X is â€”CH2)kâ€” or â€”CH2(Oâ€”CH2â€”CH2)kâ€”, k is from 1 to 10, Y is the average molecular weight of each poly(ethylene glycol) group is from about 20 kilodaltons to about 40 kilodaltons, and the molecular weight of the conjugate is from about 51 kilodaltons to about 175 kilodaltons.