Crysvita® is a recombinant fully human monoclonal IgG1 antibody against the phosphaturic hormone fibroblast growth factor 23 (FGF23).
By blocking excess FGF23 in patients, Crysvita® is intended to increase phosphate reabsorption in the kidney and increase the production of vitamin D, which enhances intestinal absorption of phosphate and calcium in patients with X linked hypophosphatemia.