Patent ID: 11891434
Assignee: CHUGAI SEIYAKU KABUSHIKI KAISHA
Field: Measurement (Instruments)
Classification: CPC C  G | IPC C  G

Claim 0:
1. A method of removing a soluble antigen from plasma, the method comprising:
(a) identifying an individual in need of having the antigen removed from the individual's plasma; and
(b) administering to the individual an antibody that is able to remove the antigen from plasma, thereby removing the antigen from the individual's plasma,
wherein the antibody comprises an antigen-binding domain and a human FcRn-binding domain,
wherein the antibody binds to the antigen through the antigen-binding domain of the antibody and has a KD(Ca2+3 μM)/KD(Ca2+2 mM) value, defined as the ratio of KD for the antigen at a 3 μM calcium ion concentration and KD for the antigen at a 2 mM calcium ion concentration, of 2 to 10,000, when KD is measured using a surface plasmon resonance technique under the following conditions:
37 degrees Celsius, pH 7.4, a running buffer comprising 0.05% polysorbate 20,
10 mmol/L N-(2-acetamido)-2-aminoethanesulfonic acid (ACES), 150 mmol/L NaCl,
and either 3 μM or 2 mM CaCl2, and where the antibody is immobilized on a CM4 sensor chip, and the antigen serves as analyte,
wherein the antibody binds to the antigen in plasma in vivo and dissociates from the bound antigen under conditions present in an endosome in vivo,
wherein the antibody is a human IgG or a humanized IgG,
wherein the antigen-binding domain comprises a light chain variable domain and a heavy chain variable domain,
wherein at least four positions selected from Kabat numbering positions 30, 31, 32, 50, and 92 of the light chain variable domain are occupied by amino acids independently selected from serine, asparagine, aspartic acid, glutamic acid, histidine, and tyrosine, and
wherein at least one of the at least four positions is occupied by glutamic acid or aspartic acid.