Patent ID: 8852888

Claim:
A method for producing a recombinant Von Willebrand Factor (rVWF) composition, the method comprising the steps of: (a) providing a basal cell culture media; (b) supplementing the basal cell culture media with copper to provide a final copper concentration of at least 2.4 μg/L; (c) providing one or more cells comprising a nucleic acid encoding a rVWF protein; (d) culturing the one or more cells in the copper supplemented cell culture media such that rVWF is expressed and excreted from the cells into a culture supernatant and the NH 4 + content of the cell culture supernatant is maintained at a concentration below 4 mM or below 10 mM; and (e) recovering at least a portion of the culture supernatant, wherein the recovered supernatant has a rVWF specific ristocetin cofactor activity of at least 30 mU/μg rVWF.