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About CRYSVITA

CRYSVITA is a FGF23 blocking antibody that targets the underlying cause of chronic hypophosphatemia in XLH—excess FGF23.1,2 It binds to and inhibits the biological activity of FGF23, restoring renal phosphorus reabsorption and increasing serum concentration of active vitamin D.1


For more information on CRYSVITA and how it works, please see Mechanism of action.

CRYSVITA is indicated for the treatment of X-linked hypophosphatemia (XLH) in adult and pediatric patients 6 months of age and older.1

For other CRYSVITA use information, please see the full Prescribing Information

CRYSVITA is manufactured by Kyowa Kirin, Inc. (U.S. License No. 2077).1

Mechanism of action for CRYSVITA

CRYSVITA is the only targeted therapy to address the underlying causes of chronic hypophosphatemia in XLH.1,3 It is a human monoclonal antibody specifically designed to inhibit the activity of FGF23.1

In XLH, CRYSVITA-mediated inhibition of FGF23 is thought to:1,4

  • Increase renal phosphate reabsorption via sodium phosphate co-transporters
  • Upregulate renal expression of 1α-hydroxylase, which increases serum concentration of active vitamin D, leading to increased intestinal phosphate absorption
Together, this can lead to normalized serum phosphorus levels.1,5

For more information on CRYSVITA and how it works, please see Mechanism of action

Efficacy and safety of CRYSVITA

Children

A phase 3 study in children with XLH between 1 and 12 years of age showed that CRYSVITA:1

  • Helped heal rickets and reduce rickets severity
  • Increased growth
  • Increased and sustained serum phosphorus levels
Adults

Two phase 3 studies in adults with XLH showed that CRYSVITA:1

  • Increased and maintained serum phosphorus levels
  • Helped heal fractures and osteomalacia
For more information on the efficacy of CRYSVITA in clinical studies, please see

Efficacy & safety in children

Efficacy & safety in adults

Children

The most common adverse reactions (≥25% in the CRYSVITA group and greater than active control) in pediatric patients with XLH were pyrexia, injection site reaction, cough, vomiting, pain in extremity, headache, tooth abscess, and dental caries.1


Adults

The most common adverse reactions (in >5% of CRYSVITA-treated patients and in at least 2 patients more than placebo) in adult patients with XLH were back pain, headache, tooth infection, restless legs syndrome, vitamin D decreased, dizziness, constipation, muscle spasms, and blood phosphorus increased.1


For more information on the safety of CRYSVITA in clinical studies, please see

Efficacy & safety in children

Efficacy & safety in adults

Dosage, administration, and storage for CRYSVITA

Children

The recommended starting dose for patients 6 months to <18 years of age who weigh:1

  • <10 kg is 1 mg/kg of body weight, rounded to the nearest 1 mg, administered every 2 weeks.
  • ≥10 kg is 0.8 mg/kg of body weight, rounded to the nearest 10 mg, administered every 2 weeks. The minimum starting dose is 10 mg up to a maximum dose of 90 mg
Adults

The recommended starting dose for patients ≥18 years of age is 1 mg/kg body weight, rounded to the nearest 10 mg, every 4 weeks. Doses may be increased up to 90 mg, administered every 4 weeks.1


For more information on dosing for CRYSVITA, please see

Dosing in children

Dosing in adults

Children

Measure fasting serum phosphorus levels every 4 weeks for the first 3 months of treatment and thereafter, as appropriate.


Adults

Assess fasting serum phosphorus on a monthly basis, measured 2 weeks post-dose, for the first 3 months of treatment and thereafter, as appropriate.


For more information on the assessment schedule for CRYSVITA, please see

Dosing in children

Dosing in adults

Children

Upon assessment, if fasting serum phosphorus levels are above the lower limit of the reference range for age and below 5 mg/dL, continue treatment with the same dose. To maintain serum phosphorus levels within the reference range for age, adjust the dose as indicated in the full Prescribing Information.1


Adults

Upon assessment, if fasting serum phosphorus is within the normal range, continue with the same dose. To maintain serum phosphorus levels within the normal range, adjust the dose as indicated in the full Prescribing Information.1




For more information on dosing adjustments for CRYSVITA, please see

Dosing in children

Dosing in adults

CRYSVITA should be administered by an HCP and via subcutaneous injection only. Injection sites should be rotated with each injection, administered at a different anatomic location than the previous injection. Injection site locations include:1

  • Upper arms
  • Upper thighs
  • Buttocks
  • Any quadrant of the abdomen
Do not inject into moles, scars, or areas where the skin is tender, bruised, red, hard, or not intact.1

For more information on the administration of CRYSVITA and general considerations, please see

Dosing in children

Dosing in adults

CRYSVITA is a sterile, preservative-free, clear to slightly opalescent and colorless to pale brown-yellow solution for subcutaneous injection. Do not use if the solution is discolored or cloudy or if the solution contains any particles or foreign particulate matter.1


For more information on the administration of CRYSVITA and general considerations, please see

Dosing in children

Dosing in adults

CRYSVITA vials must be stored in the original carton until the time of use under refrigerated conditions at 36°F to 46°F (2°C to 8°C). Keep the CRYSVITA vial in the original carton to protect it from light until the time of use.1

  • Do not freeze or shake CRYSVITA
  • Do not use CRYSVITA beyond the expiration date stamped on the carton
  • CRYSVITA vials are single-dose only. Discard any unused product
For more information on storing and handling CRYSVITA, please see Supply & storage

Treatment considerations for CRYSVITA

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.1

For more information on the use of CRYSVITA in specific populations, please see the full Prescribing Information

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.1

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

Access and support for CRYSVITA

Kyowa Kirin Cares program helps patients understand their financial options based on their insurance coverage and offers access support for eligible patients.

For more information on access and reimbursement assistance for CRYSVITA, please see Patient access

Kyowa Kirin Cares provides personalized support to your patients and caregivers throughout their treatment journey with CRYSVITA:

  • Case Managers available to answer questions
  • Help patients understand their financial options based on their insurance coverage
  • Address treatment onboarding inquiries
  • Educational information (non-medical)
For more information on patient support and access to helpful resources, please see

Patient support

Resources for your practice & patients

FGF23= fibroblast growth factor 23; HCP=healthcare professional; XLH=X-linked hypophosphatemia.

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Indication

CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23) blocking antibody indicated for the treatment of X-linked hypophosphatemia (XLH) in adult and pediatric patients 6 months 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.

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

Pediatric Patients

  • Adverse reactions reported in 10% or more of CRYSVITA-treated pediatric XLH patients across three studies are: pyrexia (55%, 44%, and 62%), injection site reaction (52%, 67%, and 23%), cough (52%), vomiting (41%, 48%, and 46%), pain in extremity (38%, 46%, and 23%), headache (34% and 73%), tooth abscess (34%, 15%, and 23%), dental caries (31%), diarrhea (24%), vitamin D decreased (24%, 37%, and 15%), toothache (23% and 15%), constipation (17%), myalgia (17%), rash (14% and 27%), dizziness (15%), and nausea (10%).
  • Postmarketing experience reported in CRYSVITA-treated pediatric XLH patients: blood phosphorus increased.

Adult Patients

  • Adverse reactions reported in more than 5% of CRYSVITA-treated adult XLH patients and in at least 2 patients more than placebo in one study are: back pain (15%), headache (13%), tooth infection (13%), restless legs syndrome (12%), vitamin D decreased (12%), dizziness (10%), constipation (9%), muscle spasms (7%), and blood phosphorus increased (6%).
  • Spinal stenosis is prevalent in adults with XLH, and spinal cord compression has been reported. It is unknown if CRYSVITA therapy exacerbates spinal stenosis or spinal cord compression.

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 COUNSELLING 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.

Indication

CRYSVITA® (burosumab-twza) is a fibroblast growth factor 23 (FGF23) blocking antibody indicated for the treatment of X-linked hypophosphatemia (XLH) in adult and pediatric patients 6 months 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.

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

Pediatric Patients

  • Adverse reactions reported in 10% or more of CRYSVITA-treated pediatric XLH patients across three studies are: pyrexia (55%, 44%, and 62%), injection site reaction (52%, 67%, and 23%), cough (52%), vomiting (41%, 48%, and 46%), pain in extremity (38%, 46%, and 23%), headache (34% and 73%), tooth abscess (34%, 15%, and 23%), dental caries (31%), diarrhea (24%), vitamin D decreased (24%, 37%, and 15%), toothache (23% and 15%), constipation (17%), myalgia (17%), rash (14% and 27%), dizziness (15%), and nausea (10%).
  • Postmarketing experience reported in CRYSVITA-treated pediatric XLH patients: blood phosphorus increased.

Adult Patients

  • Adverse reactions reported in more than 5% of CRYSVITA-treated adult XLH patients and in at least 2 patients more than placebo in one study are: back pain (15%), headache (13%), tooth infection (13%), restless legs syndrome (12%), vitamin D decreased (12%), dizziness (10%), constipation (9%), muscle spasms (7%), and blood phosphorus increased (6%).
  • Spinal stenosis is prevalent in adults with XLH, and spinal cord compression has been reported. It is unknown if CRYSVITA therapy exacerbates spinal stenosis or spinal cord compression.

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 COUNSELLING 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. CRYSVITA (burosumab-twza). US Prescribing Information. Kyowa Kirin, Inc. March 2023. 2. Glorieux FH, et al. Potential influences on optimizing long-term musculoskeletal health in children and adolescents with X-linked hypophosphatemia (XLH). Orphanet J Rare Dis. 2022;17(1):30. 3. Carpenter TO, et al. Randomized trial of the anti-FGF23 antibody KRN23 in X-linked hypophosphatemia. J Clin Invest. 2014;124(4):1587-1597. 4. Aono Y, et al. Therapeutic effects of anti-FGF23 antibodies in hypophosphatemic rickets/osteomalacia. J Bone Miner Res. 2009;24(11):1879-1888. 5. Erben RG, et al. FGF23-Klotho signaling axis in the kidney. Bone. 2017;100:62-68.

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COMM-US-CRY-0076 | March 2025