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TIO is a rare disease caused by slow-growing tumors that occur throughout the body

scalpel with plus sign above

The tumors responsible for tumor-induced osteomalacia (TIO) can be removed with surgery, which can lead to the levels of phosphorus in the body returning to normal. But the tumors are sometimes too small to find or are in a location where they can't be removed.

Tumor

The symptoms of TIO get worse over time, so it’s important to treat it as early as possible.

Bone bending in pain

Osteomalacia, or "soft bones," is a weakening of the bones due to low levels of vitamins and minerals, including phosphorus, calcium, and vitamin D. Phosphorus is a mineral that is important for bone health.

In a clinical review of 895 unique cases of TIO, the majority of cases occurred in adults between 30 and 60 years of age.

More is known about TIO than ever before, including how to treat it. Starting treatment now can help you manage the symptoms of this condition.

In people with TIO, the most common locations for fractures are:

Vertabrae

Vertebrae

Ribcage

Rib

Two bones

Femur

Pelvic area of skeleton

Pelvis

TIO can get worse over time. Speak to your doctor to see if CRYSVITA is right for you.

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Getting started on CRYSVITA can help you begin to manage this condition.

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Discover how CRYSVITA helped people with TIO

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What is CRYSVITA?

CRYSVITA is a prescription medicine used to treat adults and children 2 years of age and older with fibroblast growth factor 23 (FGF23)–related hypophosphatemia in tumor-induced osteomalacia (TIO) when the tumor cannot be located or removed.

What is CRYSVITA?

CRYSVITA is a prescription medicine used to treat adults and children 2 years of age and older with fibroblast growth factor 23 (FGF23)–related hypophosphatemia in tumor-induced osteomalacia (TIO) when the tumor cannot be located or removed.

Important Safety Information

You should not take CRYSVITA if:

  • You take an oral phosphate supplement and/or a specific form of vitamin D supplement (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
  • Your phosphorus levels from a blood sample are within or above the normal range for age.
  • You have kidney problems.

What is the most important information you should know about CRYSVITA?

  • Some patients developed allergic reactions (e.g., rash and hives) while taking CRYSVITA. Your doctor will monitor you for symptoms of an allergic reaction while you are taking CRYSVITA.
  • High levels of phosphorus in the blood have been reported in some patients taking CRYSVITA. This may be related to a risk of high calcium levels in the kidneys. Your doctor will collect blood samples to monitor your levels.
  • Administration of CRYSVITA may result in reactions at the injection site, such as hives, reddening of the skin, rash, swelling, bruising, pain, severe itching of the skin, and collection of blood outside of a blood vessel (i.e., hematoma).
  • If you are taking CRYSVITA for TIO, your doctor will have you stop your CRYSVITA treatment temporarily if you are undergoing treatment for your tumor (e.g., surgical removal of the tumor or radiation therapy).

What are the possible side effects of CRYSVITA?

  • Adverse reactions that were seen in adults with TIO are:

    • Tooth abscess
    • Muscle spasms
    • Dizziness
    • Constipation
    • Injection site reaction
    • Rash
    • Headache

Before taking CRYSVITA, tell your doctor about all of your medications (including supplements) and medical conditions, including if you:

  • Are taking oral phosphate and/or active vitamin D (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
  • Are pregnant, think you may be pregnant, or plan to become pregnant. There is not enough experience to know if CRYSVITA may harm your unborn baby. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
  • Are breastfeeding or plan to breastfeed. There is not enough experience to know if CRYSVITA passes into your breast milk. Talk with your doctor about the best way to feed your baby while you receive CRYSVITA.

While taking CRYSVITA, tell your doctor if you experience:

  • An allergic reaction such as rash or hives
  • A rash, swelling, bruising, or other reaction at the injection site
  • New or worsening restless legs syndrome

These are not all the possible side effects of CRYSVITA. Call your doctor for medical advice about side effects.

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.

What is CRYSVITA?

CRYSVITA is a prescription medicine used to treat adults and children 2 years of age and older with fibroblast growth factor 23 (FGF23)–related hypophosphatemia in tumor-induced osteomalacia (TIO) when the tumor cannot be located or removed.

Important Safety Information

You should not take CRYSVITA if:

  • You take an oral phosphate supplement and/or a specific form of vitamin D supplement (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
  • Your phosphorus levels from a blood sample are within or above the normal range for age.
  • You have kidney problems.

What is the most important information you should know about CRYSVITA?

  • Some patients developed allergic reactions (e.g., rash and hives) while taking CRYSVITA. Your doctor will monitor you for symptoms of an allergic reaction while you are taking CRYSVITA.
  • High levels of phosphorus in the blood have been reported in some patients taking CRYSVITA. This may be related to a risk of high calcium levels in the kidneys. Your doctor will collect blood samples to monitor your levels.
  • Administration of CRYSVITA may result in reactions at the injection site, such as hives, reddening of the skin, rash, swelling, bruising, pain, severe itching of the skin, and collection of blood outside of a blood vessel (i.e., hematoma).
  • If you are taking CRYSVITA for TIO, your doctor will have you stop your CRYSVITA treatment temporarily if you are undergoing treatment for your tumor (e.g., surgical removal of the tumor or radiation therapy).

What are the possible side effects of CRYSVITA?

  • Adverse reactions that were seen in adults with TIO are:

    • Tooth abscess
    • Muscle spasms
    • Dizziness
    • Constipation
    • Injection site reaction
    • Rash
    • Headache

Before taking CRYSVITA, tell your doctor about all of your medications (including supplements) and medical conditions, including if you:

  • Are taking oral phosphate and/or active vitamin D (such as calcitriol, paricalcitol, doxercalciferol, calcifediol).
  • Are pregnant, think you may be pregnant, or plan to become pregnant. There is not enough experience to know if CRYSVITA may harm your unborn baby. Report pregnancies to the Kyowa Kirin, Inc. Adverse Event reporting line at 1-844-768-3544.
  • Are breastfeeding or plan to breastfeed. There is not enough experience to know if CRYSVITA passes into your breast milk. Talk with your doctor about the best way to feed your baby while you receive CRYSVITA.

While taking CRYSVITA, tell your doctor if you experience:

  • An allergic reaction such as rash or hives
  • A rash, swelling, bruising, or other reaction at the injection site
  • New or worsening restless legs syndrome

These are not all the possible side effects of CRYSVITA. Call your doctor for medical advice about side effects.

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.