Monalizumab is a recombinant anti-CD94/NKG2A monoclonal antibody derived from human IgG4. In the H-chain,the amino acid residue is substituted at 1 position (S233P). Monalizumab is produced in CHO cells. Monalizumab is a glycoprotein (molecular weight: ca. 149,000) composed of 2 H-chains (γ4-chains) consisting of 452 amino acid residues each and 2 L-chains (κ-chains) consisting of 214 amino acid residues each.