The product is comprised of a single molecule of human factor IX (FIX) covalently linked to the constant region (Fc) domain of human IgG1 via recombinant DNA technology in a human embryonic kidney cell line (HEK293H). Eftrenonacog alfa https://www.creativebiomart.net/therapeutic-proteins/p/66/recombinant-fusion-protein-of-human-fix-and-igg1/