CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23)–blocking antibody1

CRYSVITA® (burosumab-twza) is an FGF23-blocking antibody1

Benign tumors produce excess FGF23 in TIO
Benign tumors produce excess FGF23 in TIO

In TIO, benign tumors produce excess FGF23. This suppresses renal tubular phosphate reabsorption and renal production of 1,25 dihydroxy vitamin D, which play a role in phosphate absorption in the small intestine.1,2

CRYSVITA® inhibits FGF23 activity
CRYSVITA® inhibits FGF23 activity

CRYSVITA binds to and inhibits the biological activity of FGF23, restoring renal phosphate reabsorption and increasing the serum concentration of 1,25 dihydroxy vitamin D.1

CRYSVITA targets the underlying cause of FGF23-related hypophosphatemia in TIO

Tumor-induced osteomalacia—mechanism of disease

Mechanism of disease (MOD)

Small, usually benign tumors express FGF23, which results in hypophosphatemia. Excess FGF23 activity suppresses renal tubular phosphate reabsorption and production of active vitamin D.4

CRYSVITA® for TIO—mechanism of action

Proposed mechanism of action (MOA)

Based on preclinical studies, inhibition of FGF23 is thought to restore phosphate homeostasis by promoting renal phosphate reabsorption through increased renal expression of sodium phosphate cotransporters and by increasing the renal expression of 1α-hydroxylase, a vitamin D–metabolizing enzyme involved in vitamin D production.3,4

CRYSVITA is a human monoclonal antibody specifically designed to inhibit the activity of FGF23

  1. CRYSVITA (burosumab-twza) US Prescribing Information; June 2020.

  2. Martin A, Quarles LD. Evidence for FGF23 involvement in a bone-kidney axis regulating bone mineralization and systemic phosphate and vitamin D homeostasis. Adv Exp Med Biol. 2012;728:65-83.

  3. Aono Y, Yamazaki Y, Yasutake J, et al. Therapeutic effects of anti-FGF23 antibodies in hypophosphatemic rickets/osteomalacia. J Bone Miner Res. 2009;24(11):1879-1888.

  4. Erben RG, Andrukhova O. FGF23-Klotho signaling axis in the kidney. Bone. 2017;100:62-68.