3.1
Burosumab (Crysvita, Kyowa Kirin) is monoclonal antibody that binds to and inhibits the activity of fibroblast growth factor 23 (FGF23). By inhibiting FGF23, burosumab is expected to increase reabsorption of phosphate from the kidney and, through vitamin D production, improve intestinal absorption of calcium and phosphate. Burosumab has a conditional marketing authorisation for 'the treatment of X‑linked hypophosphataemia with radiographic evidence of bone disease in children 1 year of age and older and adolescents with growing skeletons'.