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CRYSVITA® (burosumab-twza) injection 10, 20, 30 mg/mL

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TIO is an acquired form of hypophosphatemia1

Tumor-induced osteomalacia, or TIO, is an extremely rare, difficult to diagnose disease. The mean age of diagnosis is 45 years with a wide age range, including cases reported in children.1

TIO is typically caused by slow-growing, benign, phosphaturic mesenchymal tumors that can arise in soft tissues or bones anywhere in the body. These tumors secrete excess fibroblast growth factor 23 (FGF23), which results in hypophosphatemia and osteomalacia.1,2

The underlying cause of hypophosphatemia in TIO

In normal homeostasis2:

An abstract shape in a stylized protein shape labeled FGF23, which is a hormone in the bone

Normal FGF23 activity.

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Two kidneys

FGF23 plays an important role in phosphate homeostasis via renal excretion.

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The normal function of the intestines

FGF23 also helps maintain phosphate homeostasis via intestinal absorption.

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A healthy bone

Normal bone mineralization.

In TIO2:

An abstract shape in a stylized protein shape labeled FGF23, which is a hormone in the bone. A circular shape labeled tumor is next to FGF23

Tumors produce excess FGF23.

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The kidneys removing too much phosphate from the body due to excess FGF23

Excess FGF23 results in reduced renal phosphate reabsorption or “phosphate wasting.”

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Decreased intestinal phosphate absorption due to excess FGF23

Excess FGF23 also reduces renal production of active vitamin D, resulting in decreased intestinal phosphate absorption.

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Osteomalacia in the bone

Chronic hypophosphatemia.

FGF23=fibroblast growth factor 23.

TIO is a progressive disease that is commonly misdiagnosed1,2

Symptoms of TIO are nonspecific, progressive, and can lead to long-term disabilities. Patients may experience misdiagnosis or delayed diagnosis for several years, so it is vital that TIO is treated as soon as possible.

95%

misdiagnosis rate

In a retrospective study, 95% (137/144) of patients were initially misdiagnosed.3

1,725

cases

As of 2021, there have only been 1,725 cases reported worldwide.4

Presentation of TIO can vary2,3,5

Excess FGF23 is the underlying cause of symptoms for patients with TIO. While the presentation and severity of symptoms vary, bone pain may be their initial symptom. This often starts in the lower limbs, most commonly in the feet and ankles. Other symptoms of TIO can include, but are not limited to:

A bent knee joint with surrounding tissue

Muscle pain

The vertebral column

Bone pain

A silhouette of a person leaning over meant to resemble being fatigued

Fatigue

CRYSVITA has not been studied or approved for treating muscle pain, bone pain, or fatigue.

Tumor removal can be curative, but may not be possible under certain circumstances.2

Help restore and maintain serum phosphorus levels with CRYSVITA6

How it works
Gilberto, a patient currently on CRYSVITA, smiling while standing with his hand in his pocket

Gilberto,
currently on
CRYSVITA

Indication

CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23) blocking antibody indicated for the treatment of FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors that cannot be curatively resected or localized in adult and pediatric patients 2 years of age and older.

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Indication

CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23) blocking antibody indicated for the treatment of FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors that cannot be curatively resected or localized in adult and pediatric patients 2 years of age and older.

Important Safety Information

CONTRAINDICATIONS

CRYSVITA is contraindicated:

  • In concomitant use with oral phosphate and/or active vitamin D analogs (e.g., calcitriol, paricalcitol, doxercalciferol, calcifediol) due to the risk of hyperphosphatemia.
  • When serum phosphorus is within or above the normal range for age.
  • In patients with severe renal impairment or end stage renal disease because these conditions are associated with abnormal mineral metabolism.

WARNINGS AND PRECAUTIONS

Hypersensitivity

  • Hypersensitivity reactions (e.g., rash, urticaria) have been reported in patients with CRYSVITA. Discontinue CRYSVITA if serious hypersensitivity reactions occur and initiate appropriate medical treatment.

Hyperphosphatemia and Risk of Nephrocalcinosis

  • Increases in serum phosphorus to above the upper limit of normal may be associated with an increased risk of nephrocalcinosis. For patients already taking CRYSVITA, dose interruption and/or dose reduction may be required based on a patient’s serum phosphorus levels.
  • Patients who undergo treatment of the underlying tumor should have dosing interrupted and adjusted to prevent hyperphosphatemia.

Hypercalcemia

  • Increases in serum calcium have been reported in patients treated with CRYSVITA. Patients with risk factors such as pre-existing hyperparathyroidism, prolonged immobilization, dehydration, hypervitaminosis D, or renal impairment, are at higher risk of hypercalcemia. Monitor these patients for serum calcium and parathyroid hormone levels before and during CRYSVITA treatment for moderate to severe hypercalcemia. In patients with moderate to severe hypercalcemia, CRYSVITA should not be administered until hypercalcemia is adequately managed.

Injection Site Reactions

  • Administration of CRYSVITA may result in local injection site reactions. Discontinue CRYSVITA if severe injection site reactions occur and administer appropriate medical treatment.

ADVERSE REACTIONS

Adult Patients

  • Adverse reactions reported in more than 10% of CRYSVITA-treated adult TIO patients in two studies are: tooth abscess (19%), muscle spasms (19%), dizziness (15%), constipation (15%), injection site reaction (15%), rash (15%), and headache (11%).

USE IN SPECIFIC POPULATIONS

  • There are no available data on CRYSVITA use in pregnant women to inform a drug-associated risk of adverse developmental outcomes. Serum phosphorus levels should be monitored throughout pregnancy. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
  • There is no information regarding the presence of CRYSVITA in human milk or the effects of CRYSVITA on milk production or the breastfed infant. Therefore, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for CRYSVITA and any potential adverse effects on the breastfed infant from CRYSVITA or from the underlying maternal condition.

PATIENT COUNSELING INFORMATION

  • Advise patients not to use any oral phosphate and/or active vitamin D analog products.
  • Instruct patients to contact their physician if hypersensitivity reactions, injection site reactions, and restless legs syndrome induction or worsening of symptoms occur.

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/
medwatch. You may also report side effects to Kyowa Kirin, Inc. at 1-844-768-3544.

For important risk and use information, please see the full Prescribing Information for CRYSVITA.

References:

  • 1. Minisola S, Peacock M, Fukumoto S, et al. Tumour-induced osteomalacia. Nat Rev Dis Primers. 2017;3:17044. doi:10.1038/nrdp.2017.44 2. Dahir K, Zanchetta MB, Stanciu I, et al. Diagnosis and management of tumor-induced osteomalacia: perspectives from clinical experience. J Endocr Soc. 2021;5(9):bvab099. doi:10.1210/jendso/bvab099 3. Feng J, Jiang Y, Wang O, et al. The diagnostic dilemma of tumor induced osteomalacia: a retrospective analysis of 144 cases. Endocr J. 2017;64(7):675-683. doi:10.1507/endocrj.EJ16-0587 4. Rendina D, Abate V, Cacace G, et al. Tumor-induced osteomalacia: a systematic review and individual patient's data analysis. J Clin Endocrinol Metab. 2022;107(8):e3428-e3436. doi:10.1210/clinem/dgac253 5. Jerkovich F, Nuñez S, Mocarbel Y, Pignatta A, Elías N, Cassinelli H, et al. Burden of disease in patients with tumor-induced osteomalacia. JBMR Plus. 2021;5(2):e10436. doi:10.1002/jbm4.10436 6. CRYSVITA (burosumab-twza). US Prescribing Information. Kyowa Kirin, Inc.; April 2026.
Indication

CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23) blocking antibody indicated for the treatment of FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors that cannot be curatively resected or localized in adult and pediatric patients 2 years of age and older.

Important Safety Information

CONTRAINDICATIONS

CRYSVITA is contraindicated:

  • In concomitant use with oral phosphate and/or active vitamin D analogs (e.g., calcitriol, paricalcitol, doxercalciferol, calcifediol) due to the risk of hyperphosphatemia.
  • When serum phosphorus is within or above the normal range for age.
  • In patients with severe renal impairment or end stage renal disease because these conditions are associated with abnormal mineral metabolism.

WARNINGS AND PRECAUTIONS

Hypersensitivity

  • Hypersensitivity reactions (e.g., rash, urticaria) have been reported in patients with CRYSVITA. Discontinue CRYSVITA if serious hypersensitivity reactions occur and initiate appropriate medical treatment.

Hyperphosphatemia and Risk of Nephrocalcinosis

  • Increases in serum phosphorus to above the upper limit of normal may be associated with an increased risk of nephrocalcinosis. For patients already taking CRYSVITA, dose interruption and/or dose reduction may be required based on a patient’s serum phosphorus levels.
  • Patients who undergo treatment of the underlying tumor should have dosing interrupted and adjusted to prevent hyperphosphatemia.

Hypercalcemia

  • Increases in serum calcium have been reported in patients treated with CRYSVITA. Patients with risk factors such as pre-existing hyperparathyroidism, prolonged immobilization, dehydration, hypervitaminosis D, or renal impairment, are at higher risk of hypercalcemia. Monitor these patients for serum calcium and parathyroid hormone levels before and during CRYSVITA treatment for moderate to severe hypercalcemia. In patients with moderate to severe hypercalcemia, CRYSVITA should not be administered until hypercalcemia is adequately managed.

Injection Site Reactions

  • Administration of CRYSVITA may result in local injection site reactions. Discontinue CRYSVITA if severe injection site reactions occur and administer appropriate medical treatment.

ADVERSE REACTIONS

Adult Patients

  • Adverse reactions reported in more than 10% of CRYSVITA-treated adult TIO patients in two studies are: tooth abscess (19%), muscle spasms (19%), dizziness (15%), constipation (15%), injection site reaction (15%), rash (15%), and headache (11%).

USE IN SPECIFIC POPULATIONS

  • There are no available data on CRYSVITA use in pregnant women to inform a drug-associated risk of adverse developmental outcomes. Serum phosphorus levels should be monitored throughout pregnancy. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
  • There is no information regarding the presence of CRYSVITA in human milk or the effects of CRYSVITA on milk production or the breastfed infant. Therefore, the developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for CRYSVITA and any potential adverse effects on the breastfed infant from CRYSVITA or from the underlying maternal condition.

PATIENT COUNSELING INFORMATION

  • Advise patients not to use any oral phosphate and/or active vitamin D analog products.
  • Instruct patients to contact their physician if hypersensitivity reactions, injection site reactions, and restless legs syndrome induction or worsening of symptoms occur.

You may report side effects to the FDA at (800) FDA-1088 or www.fda.gov/
medwatch. You may also report side effects to Kyowa Kirin, Inc. at 1-844-768-3544.

For important risk and use information, please see the full Prescribing Information for CRYSVITA.

References:

  • 1. Minisola S, Peacock M, Fukumoto S, et al. Tumour-induced osteomalacia. Nat Rev Dis Primers. 2017;3:17044. doi:10.1038/nrdp.2017.44 2. Dahir K, Zanchetta MB, Stanciu I, et al. Diagnosis and management of tumor-induced osteomalacia: perspectives from clinical experience. J Endocr Soc. 2021;5(9):bvab099. doi:10.1210/jendso/bvab099 3. Feng J, Jiang Y, Wang O, et al. The diagnostic dilemma of tumor induced osteomalacia: a retrospective analysis of 144 cases. Endocr J. 2017;64(7):675-683. doi:10.1507/endocrj.EJ16-0587 4. Rendina D, Abate V, Cacace G, et al. Tumor-induced osteomalacia: a systematic review and individual patient's data analysis. J Clin Endocrinol Metab. 2022;107(8):e3428-e3436. doi:10.1210/clinem/dgac253 5. Jerkovich F, Nuñez S, Mocarbel Y, Pignatta A, Elías N, Cassinelli H, et al. Burden of disease in patients with tumor-induced osteomalacia. JBMR Plus. 2021;5(2):e10436. doi:10.1002/jbm4.10436 6. CRYSVITA (burosumab-twza). US Prescribing Information. Kyowa Kirin, Inc.; April 2026.

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COMM-US-CRY-0997 June 2026