Human fcrn-binding modified antibodies and methods of use

An antibody, comprising a first Fc-region polypeptide and a second Fc-region polypeptide, wherein the first and the second Fc-region polypeptide are both of human IgG1 of SEQ ID NO:

• 60 and comprise the mutations H310A, H433A, and Y436A (numbering according to Kabat EU index numbering system) in the first Fc-region polypeptide and in the second Fc-region polypeptide, wherein:
• i) the first IgG1 Fc-region polypeptide and the second IgG1 Fc-region polypeptide comprise no mutations other than those stated above, or
• ii) the first IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A and the second IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, or
• iii) the first IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, 1235A, P329G and the second IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, P329G, or
• iv) the first IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, S354C, T366W and the second IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, Y349C, T366S, L368A, Y407V, or
• v) the first IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, P329G, S354C, T366W and the second IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations L234A, L235A, P329G, Y349C, T366S, L368A, Y407V, or
• vi) the first IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutation K392D and the second IgG1 Fc-region polypeptide is a human IgG1 Fc-region polypeptide with the mutations D399K, D356K, and/or E357K.