This CPB has been revised to add the following criteria for burosumab-twza (Crysvita) therapy: (i) for X-linked hypophosphatemia, added radiographic evidence of rickets or bone disease, and (ii) for continuation of therapy, added examples of evidence of benefit of disease improvement or disease stability (e.g., increase or normalization in serum phosphate, improvement in bone and joint pain, reduction in fractures, improvement in skeletal deformities) and updated to include members who are currently receiving the requested medication through a "previously authorized" pharmacy or medical benefit. This CPB has been revised for X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO) to require FGF23 level to be above the upper limit of normal or abnormal for the assay. Previous version required FGF23 level to be greater than 30 pg/mL for XLH and FGF23 level greater than 100 pg/mL for TIO.