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CRYSVITA was effective in adults with XLH

Actor portrayal

Two clinical studies of adults with XLH have shown that CRYSVITA can help by:

Periodic table abbreviation of phosphorus

Increasing and maintaining phosphorus levels in the blood

Leg with a cast

Helping to heal osteomalacia

Bone with fractures or pseudofractures

Healing fractures and pseudofractures

Study designs

The risks and benefits of treatment with CRYSVITA were studied in 148 adults with XLH

Click on the tabs below to see how each study was conducted

Number of patients: 134

Ages: 19 to 66 years

Length of treatment: 48 weeks

Number of patients: 14

Ages: 25 to 52 years

Length of treatment: 48 weeks

increasing phosphorus levels

CRYSVITA improved phosphorus levels

CRYSVITA helped increase and maintain phosphorus levels in the blood within the normal range for most people in the study

In Study 4:

  • Adults with XLH were given either CRYSVITA (68 adults) or placebo (66 adults) every 4 weeks for 24 weeks
  • The amount of phosphorus in their blood, described as serum phosphorus, was measured
  • At week 24, adults who started on placebo were switched to CRYSVITA every 4 weeks. Both groups were re-evaluated at week 48

More people on CRYSVITA saw their phosphorus levels increase to the normal range* compared to placebo in Study 4 (between baseline and 24 weeks)

Periodic table of abbreviation for phosphorus with an arrow pointing up

CRYSVITA

94%

64 out of 68 patients
who received
CRYSVITA

Versus

(P<0.0001)

Placebo

8%

5 out of 66 patients
who received placebo

People taking CRYSVITA from the start maintained their phosphorus levels through week 48. People who switched to CRYSVITA at 24 weeks increased their phosphorus levels between weeks 24 and 48

Periodic table of abbreviation for phosphorus with an arrow pointing up

CRYSVITA

84%

57 out of 68 patients
who continued with
CRYSVITA

Versus

(P<0.0001)

Placebo to CRYSVITA

89%

59 out of 66 patients
who switched from
placebo to CRYSVITA

At baseline, patients in both the CRYSVITA and placebo groups had phosphorus levels below the normal range. During the 24 weeks of treatment with CRYSVITA or placebo, more patients achieved phosphorus levels within the normal range in the CRYSVITA group than in the placebo group. After 24 weeks of treatment, all patients were placed on CRYSVITA. Patients receiving CRYSVITA from the start of the study maintained their phosphorus levels through week 48. Patients who transitioned to CRYSVITA treatment at week 24 saw a rapid increase in phosphorus levels after starting on treatment, similar to what was observed in the patients who began CRYSVITA at the beginning of the study.

*

Normal levels of phosphorus in the blood for this group of patients ranged from 2.5 to 4.5 milligrams/deciliter (mg/dL). The normal range of phosphorus varies by age and sex.

healing fractures

CRYSVITA helped heal fractures and pseudofractures

CRYSVITA helped heal more fractures and pseudofractures compared to placebo

In Study 4:

  • One group of 68 adults received CRYSVITA for 48 weeks
  • One group of 66 adults received placebo for 24 weeks and then CRYSVITA for 24 weeks
  • At the beginning of Study 4, there were 65 total fractures/pseudofractures in the CRYSVITA group and 91 total fractures/pseudofractures in the placebo group

Percentage of fractures and pseudofractures that were completely healed

Line graph showing increase in fully healed fractures with CRYSVITA vs placebo

After week 24 of Study 4:

  • During treatment through week 24, a total of 6 new fractures or pseudofractures appeared in 68 patients in the CRYSVITA group compared to 8 new abnormalities in 66 patients in the placebo group
  • Adults who continued receiving CRYSVITA showed continued healing of fractures at week 48
    • Healing of 8/14 active fractures (57%)
    • Healing of 33/51 active pseudofractures (65%)
  • Adults who switched from placebo to CRYSVITA showed healing of fractures at week 48
    • Healing of 6/13 active fractures (46%)
    • Healing of 26/78 active pseudofractures (33%)
Line graph showing increase in fully healed fractures with CRYSVITA vs placebo
OSTEOMALACIA

CRYSVITA helped heal osteomalacia

CRYSVITA improved bone mineralization, or bone hardening, in Study 5

In Study 5:

  • Small samples of bone were taken from 14 adults with XLH and examined for signs of healing of osteomalacia
  • Bone samples were taken before the patients started treatment with CRYSVITA and then again after the patients were treated with CRYSVITA every 4 weeks for 48 weeks
  • Healing of osteomalacia was observed in 10 out of 14 patients. Their bone biopsies showed a 57% reduction in osteoid volume to bone volume (OV/BV), which is a measurement of unmineralized bone
Leg with cast and arrow pointing down
57%
Reduction in unmineralized or soft bone

(at 48 weeks on CRYSVITA)

PATIENT-REPORTED RESULTS

CRYSVITA helped improve XLH-related joint stiffness

People on CRYSVITA reported an improvement in their joint stiffness compared with those on placebo (lower scores reflect symptom improvement). No significant difference between CRYSVITA and placebo was observed in patient-reported pain intensity or physical function at week 24.

Bar graph of improvement in joint stiffness

In Study 4, patient-reported stiffness was measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). At week 24, CRYSVITA showed improvement from baseline (-7.9) compared with placebo (+0.3) in the stiffness severity score (range 0 to 100; lower scores reflect less severe symptoms).

Learn more about the possible side effects of CRYSVITA in adults

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What is CRYSVITA?

CRYSVITA is a prescription medicine used to treat adults and children 6 months of age and older with X-linked hypophosphatemia (XLH).

What is CRYSVITA?

CRYSVITA is a prescription medicine used to treat adults and children 6 months of age and older with X-linked hypophosphatemia (XLH).

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. Your treatment may need to be discontinued for serious allergic reactions.
  • 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. If you are already taking CRYSVITA, dose interruption and/or dose reduction may be required based on your serum phosphorus 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). Call your doctor if you develop an injection site reaction. CRYSVITA may be discontinued if severe injection site reactions occur.

What are the possible side effects of CRYSVITA?

  • Adverse reactions that were seen in children with XLH are:

    • Fever
    • Injection site reaction
    • Cough
    • Vomiting
    • Pain in arms and legs
    • Headache
    • Tooth abscess
    • Dental cavities
    • Diarrhea
    • Decreased vitamin D levels
    • Toothache
    • Constipation
    • Muscle pain
    • Rash
    • Dizziness
    • Nausea

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

    • Back pain
    • Headache
    • Tooth infection
    • Restless legs syndrome
    • Decreased vitamin D levels
    • Dizziness
    • Constipation
    • Muscle spasms
    • Phosphorus levels increased in the blood
  • Narrowing of the spaces within the spine is common in adults with XLH, and pressure on the spinal cord has been reported in adults taking CRYSVITA. It is not known if taking CRYSVITA worsens the narrowing of the spaces within the spine or the pressure on the spinal cord.

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 6 months of age and older with X-linked hypophosphatemia (XLH).

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. Your treatment may need to be discontinued for serious allergic reactions.
  • 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. If you are already taking CRYSVITA, dose interruption and/or dose reduction may be required based on your serum phosphorus 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). Call your doctor if you develop an injection site reaction. CRYSVITA may be discontinued if severe injection site reactions occur.

What are the possible side effects of CRYSVITA?

  • Adverse reactions that were seen in children with XLH are:

    • Fever
    • Injection site reaction
    • Cough
    • Vomiting
    • Pain in arms and legs
    • Headache
    • Tooth abscess
    • Dental cavities
    • Diarrhea
    • Decreased vitamin D levels
    • Toothache
    • Constipation
    • Muscle pain
    • Rash
    • Dizziness
    • Nausea

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

    • Back pain
    • Headache
    • Tooth infection
    • Restless legs syndrome
    • Decreased vitamin D levels
    • Dizziness
    • Constipation
    • Muscle spasms
    • Phosphorus levels increased in the blood
  • Narrowing of the spaces within the spine is common in adults with XLH, and pressure on the spinal cord has been reported in adults taking CRYSVITA. It is not known if taking CRYSVITA worsens the narrowing of the spaces within the spine or the pressure on the spinal cord.

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.