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Meet Aly,a real CRYSVITA patient

CRYSVITA was effective in treating XLH1

Two clinical studies showed that CRYSVITA:1

Illustration of phosphorus from the periodic table, with a transparent blue circle in the top corner

Increased and maintained serum phosphorus levels

Illustration of two parallel bones that bend inward, with a transparent blue circle in the top corner

Helped heal fractures and osteomalacia

Study Design

Study 4 | Phase 3, randomized1

CRYSVITA was studied in a randomized, double-blind, placebo-controlled phase 3 study in 134 adult patients with XLH. Patients were randomized to receive CRYSVITA 1 mg/kg every 4 weeks (n=68) or placebo (n=66) for 24 weeks, followed by a 24-week open-label period during which all patients received CRYSVITA.1

A figure showing the treatment arms of Study 4

Primary endpoint:2

  • Proportion of patients achieving mean serum phosphorus levels above the lower limit of normal at the midpoint of dosing interval, averaged across dose cycles from baseline to week 24

Secondary endpoints:2

  • Change from baseline to week 24 in joint stiffness and physical function (as assessed by the Western Ontario and McMaster Universities Osteoarthritis Index/WOMAC) and pain (as assessed by Brief Pain Inventory)
  • Change from baseline in serum phosphorus concentration at each study visit

Additional endpoints:3

  • Resolution of pre-existing active pseudofractures and/or fractures at postbaseline visits, as defined by skeletal survey
  • Number of patients with adverse events (AEs), serious adverse events (SAEs), and AEs leading to discontinuation

*Maximum dose was 90 mg total.2

Study 5 | Phase 34

CRYSVITA was studied in a 48-week, open-label, single-arm study in 14 adult patients with XLH. Patients received CRYSVITA 1 mg/kg every 4 weeks.4

A figure showing the treatment arms for the CRYSVITA Study 5

Primary endpoint:4

  • Percent change from baseline to week 48 in osteoid volume to bone volume as determined by iliac crest biopsies

Secondary endpoints:4

  • Percent change from baseline in additional histomorphometric parameters, including:
    • Osteoid thickness
    • Mineralization lag time

Safety endpoint:4

  • Number of patients with adverse events (AEs), serious adverse events (SAEs), and AEs leading to discontinuation.

†Maximum dose was 90 mg total.5

‡Second biopsy was only performed if osteomalacia was present in baseline biopsy.4

In both studies of adult patients with XLH, oral phosphate and active vitamin D analogs were not allowed.1

Disease burden at baseline1,2,4

Category Study 4 (n=134) Study 5 (n=14)
Mean age, years (range) 40 (19-66) 40 (25-52)
Male, n (%) 47 (35%) 6 (43%)
Mean serum phosphorus, mg/dL (SD) 1.98 (0.31) 2.2 (0.4)
Prior therapy, including oral phosphate and active vitamin D analogs, % 90% 86%
Symptoms of osteomalacia 100% had skeletal pain associated with osteomalacia/XLH

52% had active fractures/pseudofractures located predominantly in femurs, tibias/fibulas, and metatarsals of feet		 43% had evidence of prior fractures, 29% had active pseudofractures
Category

Mean age, years (range)
Study 4 (n=134)
40 (19-66)
Study 5 (n=14)
40 (25-52)
Category

Male, n (%)
Study 4 (n=134)
47 (35%)
Study 5 (n=14)
6 (43%)
Category

Mean serum phosphorus, mg/dL (SD)
Study 4 (n=134)
1.98 (0.31)
Study 5 (n=14)
2.2 (0.4)
Category

Prior therapy, including oral phosphate and active vitamin D analogs, %
Study 4 (n=134)
90%
Study 5 (n=14)
86%
Category
Symptoms of osteomalacia
Symptoms of osteomalacia
Study 4 (n=134)
100% had skeletal pain associated with osteomalacia/XLH

52% had active fractures/pseudofractures located predominantly in femurs, tibias/fibulas, and metatarsals of feet
Study 5 (n=14)
43% had evidence of prior fractures, 29% had active pseudofractures

SD=standard deviation.

Change in serum phosphorus levels

STUDY 4 | PRIMARY ENDPOINT*

More patients on CRYSVITA increased and maintained serum phosphorus levels over 24 weeks1

An icon of the phosphorus

94%

CRYSVITA

(95% CI: 85.8, 97.7)

A versus symbol

P<0.0001||

An icon of the phosphorus

8%

Placebo

(95% CI: 3.3, 16.5)

Through week 24, patients achieved mean serum phosphorus levels above the lower limit of normal (LLN) of 2.5 mg/dL (0.81 mmol/L):1,2

  • CRYSVITA arm: 94% (64 out of 68)
  • Placebo arm: 8% (5 out of 66)

Serum phosphorus was maintained with continued CRYSVITA treatment through week 48.1

§The primary efficacy endpoint was the proportion of patients achieving a mean serum phosphorus concentration above the LLN of 2.5 mg/dL (0.81 mmol/L) averaged across the midpoints of dosing intervals between baseline and week 24.1,2

||P-value is from Cochran-Mantel-Haenszel (CMH) testing for association between achieving the primary endpoint and treatment group, adjusting for randomization stratification.1

LLN is 2.5 mg/dL. The range of normal levels of serum phosphorus is 2.5 mg/dL to 4.5 mg/dL. Note that the range of normal levels of phosphorus differ based on age and sex.1,6

||P-value is from Cochran-Mantel-Haenszel (CMH) testing for association between achieving the primary endpoint and treatment group, adjusting for randomization stratification.1

CI=confidence interval.

STUDY 4 | SECONDARY ENDPOINT§

CRYSVITA increased mean serum phosphorus levels within the normal range1

Mean serum phosphorus levels in adults receiving CRYSVITA every 4 weeks or receiving placebo1,#

button to expand image A figure showing the mean serum phosphorus levels in adults receiving CRYSVITA every 4 weeks or placebo
Show description

A figure showing the mean serum phosphorus levels in adults receiving CRYSVITA every 4 weeks or placebo.

  • Week 0 – CRYSVITA 1.68mg/dL, Placebo 1.60mg/dL
  • Week 22 – CRYSVITA 2.73mg/dL, Placebo 1.69mg/dL
  • Week 24 – CRYSVITA 2.21mg/dL, Placebo 1.73mg/dL

In Study 4, there was a significant increase from baseline through week 24 in mean serum phosphorus levels with CRYSVITA compared with placebo. Patients treated with CRYSVITA maintained mean serum phosphorus levels within the normal range through week 48.1

#Mean serum phosphorus level (mg/dL). The dotted line represents the lower limit of normal (LLN, 2.5 mg/dL). Normal levels of serum phosphorus range from 2.5 to 4.5 mg/dL. Note that the normal levels of serum phosphorus vary by age and sex. At baseline, mean (SD) serum phosphorus levels were 2.0 (0.30) mg/dL and 1.9 (0.32) mg/dL for the CRYSVITA and placebo groups, respectively. Through week 24, mean serum phosphorus levels across midpoints of dose intervals (2 weeks post-dose) were 3.2 (0.53) mg/dL and 2.1 (0.30) mg/dL for the CRYSVITA and placebo groups, respectively.1,6

SD=standard deviation.

Joint stiffness

STUDY 4 | SECONDARY ENDPOINT

CRYSVITA was shown to improve XLH-related joint stiffness; no significant differences were noted in pain and physical function1

WOMAC stiffness1,2,††

button to expand image A figure showing the rates of WOMAC joint stiffness in adulsts receiving CRYSVITA or placebo
Show description

A figure showing the rates of WOMAC joint stiffness in adulsts receiving CRYSVITA or placebo. At Week 24 CRYSVITA has a -7.9 change from baseline, Placebo has a 0.3 change from baseline.

Study 4 evaluated patient-reported XLH-related symptoms (pain, joint stiffness, and physical function). CRYSVITA was shown to improve patient-reported joint stiffness compared with placebo; no significant differences were noted in patient-reported pain intensity or physical function score at 24 weeks. Patient-reported joint stiffness was assessed using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC).1,2

CRYSVITA improved XLH-related joint stiffness from baseline to week 24:1

  • The CRYSVITA arm showed a mean improvement from baseline (-7.9) compared with the placebo arm (+0.3) in the stiffness severity score (range 0 to 100; lower scores reflect less severe symptoms)

††The estimates of LS means at week 24 are from the GEE model. Mean (SD) baseline stiffness scores were 64.7 (20.25) and 61.4 (20.77) in the CRYSVITA and placebo groups, respectively.1,2

GEE=generalized estimating equation; LS=least squares; WOMAC=Western Ontario and McMaster Universities Osteoarthritis Index.

Osteomalacia healing

STUDY 5 | PRIMARY AND SECONDARY ENDPOINT

CRYSVITA improved the healing of osteomalacia1,4

Bone mineralization, as assessed by histomorphometry1,4,**

button to expand image A figure showing bone mineralization, as assessed by histomorphometry at baseline and after 48 weeks of CRYSVITA treatment
Show description

A figure showing bone mineralization, as assessed by histomorphometry at baseline and after 48 weeks of CRYSVITA treatment.

  • Osteoid volume/bone volume (Primary endpoint) – Baseline 26.1%, CRYSVITA 11.9% (57% Reduction)
  • Osteoid thickness (Secondary endpoint) – Baseline 17.2 μm, CRYSVITA 11.6 μm (33% Reduction)
  • Mineralization lag time (Secondary endpoint) – Baseline 580 days, CRYSVITA 170 days (74% reduction)

In Study 5:

  • Histological and histomorphometric assessments of iliac bone crest (biopsies) were examined for signs of osteomalacia healing1
  • CRYSVITA improved healing at week 48, with significant reductions in osteoid volume to bone volume (OV/BV), osteoid thickness (O.Th), and mineralization lag time (MLt)1,5
    • In 10 patients, the mean (SD) score decreased in OV/BV from 26% (12.4) at baseline to 11% (6.5), a 57% reduction
    • O.Th declined in 11 patients from a mean (SD) of 17 (4.1) μm to 12 (3.1) μm, a 33% reduction
    • In 6 patients, MLt was reduced from a mean (SD) of 594 (675) days to 156 (77) days, a 74% decrease

**Reference values (in postmenopausal women) were defined as 0.3% to 3.1% for osteoid volume to bone volume; 5.5 to 12 μm for osteoid thickness; and 15 to 50 days for mineralization lag time.5

SD=standard deviation.

Osteomalacia and bone histomorphom
etry overview

Mineralization of the bone matrix (osteoid) is a critical step during bone formation. During this process, minerals are deposited to allow the “hardening” of the matrix into bone, hence the term mineralization.

In Study 5, histological assessments of the iliac bone crest were used to determine the histomorphometric features of bone associated with osteomalacia.5

Normal bone

Cross-section of bone showing a thin orange layer labelled “osteoid” and thicker light blue and dark blue layers labelled “new bone” and “old bone,” respectively.

Normal bone

An image of normal bone showing mineralized bone in green, and unmineralized osteoid in orange or red.

Mineralized bone is shown in green and unmineralized osteoid is shown in orange or red.8

Normal femur

An X-ray of a normal femur.

In a normal bone: 8

  • Osteoid volume to bone volume (OV/BV) ratio is the amount of unmineralized bone matrix (osteoid) relative to the total amount of bone (mineralized and unmineralized)9
  • Osteoid thickness (O.Th) is a measurement of the width of mineralized bone matrix (osteoid)9
  • Mineralization lag time (MLt) is the average interval of time between osteoid formation and osteoid mineralization5,9

Osteomalacia

Cross-section of bone showing thick orange and dark blue layers labelled osteoid and old bone, respectively, and a thinner light blue layer labelled new bone.

XLH (osteomalacia)

An image of bone showing mineralized bone in green, and prominent unmineralized osteoid in orange or red.

Mineralized bone is shown in green and unmineralized osteoid is shown in orange or red.8

Pseudofracture

An X-ray of a femur with a pseudofracture.

Osteomalacia is characterized by the following histomorphometric features:10,11

  • Increased osteoid volume to bone volume
  • Increased osteoid thickness
  • Prolonged mineralization lag time

Together, these indicate a greater presence of osteoid relative to mineralized bone, indicative of defective mineralization.10,11

Fracture healing

STUDY 4 | EXPLORATORY ENDPOINT

CRYSVITA helped heal osteomalacia-related fractures/
pseudofractures1

Switching to CRYSVITA from placebo led to a higher rate of fracture healing1,3

button to expand image A figure showing the rates of fracture healing in adults receiving CRYSVITA vs. placebo
Show description

A figure showing the rates of fracture healing in adults receiving CRYSVITA vs. placebo.

  • Week 24 – CRYSVITA 43% (28/65 Complete healing), Placebo 8% (7/91 Complete healing),
  • Week 48 – CRYSVITA 63% (41/65 Complete healing), Placebo 35% (32/91 Complete healing)

At week 24, 43% of baseline fractures/pseudofractures were healed in the CRYSVITA arm. During the open-label treatment period, patients who continued receiving CRYSVITA showed a higher rate of fracture healing with 63% of fractures/pseudofractures healed at week 48.1,3,12

A total of 6 new fractures or pseudofractures occurred among the 68 patients receiving CRYSVITA, compared with 8 new abnormalities in 66 patients receiving placebo.1

Radiographic examples of demonstrated osteomalacia-related pseudofracture healing2

The radiographic examples show pseudofracture healing from baseline to week 24 in a 38-year-old female patient with XLH who received CRYSVITA every 4 weeks in Study 4.

Pseudofracture at baseline2

An X-ray image of a bone with a pseudofracture, with a zoomed-in image of the fracture.

Healed pseudofractures at week 24 with CRYSVITA2

An X-ray image of a bone with a pseudofracture after 24 weeks of CRYSVITA, with a zoomed-in image of the healed fracture.

Individual results may vary.

Safety

STUDY 4 | SAFETY ENDPOINT

CRYSVITA clinical safety profile in adults with XLH

Adverse reactions (>5%) in CRYSVITA-treated patients and in ≥2 patients more than with placebo in the 24-week placebo-controlled period of Study 41

Adverse Reaction Crysvita
(n=68) 		Placebo
(n=66)
Back pain 15% 9%
Headaches‡‡ 13% 9%
Tooth infection§§ 12% 9%
Restless legs syndrome 12% 5%
Vitamin D decreased|||| 12% 5%
Dizziness 10% 6%
Muscle spasms 7% 3%
Constipation 9% 0%
Blood phosphorus increased¶¶ 6% 0%
Adverse Reaction

Back pain
Crysvita
(n=68)
15%
Placebo
(n=66)
9%
Adverse Reaction

Headaches ‡‡
Crysvita
(n=68)
13%
Placebo
(n=66)
9%
Adverse Reaction

Tooth infection §§
Crysvita
(n=68)
12%
Placebo
(n=66)
9%
Adverse Reaction

Restless legs syndrome
Crysvita
(n=68)
12%
Placebo
(n=66)
5%
Adverse Reaction

Vitamin D decreased ||||
Crysvita
(n=68)
12%
Placebo
(n=66)
5%
Adverse Reaction

Dizziness
Crysvita
(n=68)
10%
Placebo
(n=66)
6%
Adverse Reaction

Muscle spasms
Crysvita
(n=68)
7%
Placebo
(n=66)
3%
Adverse Reaction

Constipation
Crysvita
(n=68)
9%
Placebo
(n=66)
0%
Adverse Reaction

Blood phosphorus increased¶¶
Crysvita
(n=68)
6%
Placebo
(n=66)
0%

n=total number of patients who received at least 1 dose of CRYSVITA or placebo.

‡‡Headache includes: headache and head discomfort.1

§§Tooth infection includes: tooth abscess and tooth infection.1

||||Vitamin D decreased includes: vitamin D deficiency, blood 25-hydroxycholecalciferol decreased, and vitamin D decreased.1

¶¶Blood phosphorus increased includes: blood phosphorus increased and hyperphosphatemia.1

The 24-week placebo-controlled study was followed by a 24-week open-label treatment period in which all patients received CRYSVITA subcutaneously every 4 weeks. No new adverse reactions were identified in the open-label extension period.1

Adverse reactions:

Outline of a person with grey circles of different sizes on their body

Hypersensitivity reactions

In the double-blind period of Study 4, approximately 6% of patients in both the CRYSVITA and placebo treatment groups experienced a hypersensitivity event. The events were mild or moderate and did not require discontinuation.1

Illustration of phosphorus from the periodic table

Hyperphosphatemia

In the double-blind period of Study 4, 7% of patients in the CRYSVITA treatment group experienced hyperphosphatemia, meeting the protocol-specified criteria for dose reduction (either a single serum phosphorus greater than 5.0 mg/dL or serum phosphorus greater than 4.5 mg/dL [the upper limit of normal] on 2 occasions). The hyperphosphatemia was managed with dose reduction. The dose for all patients meeting the protocol-specified criteria was reduced by 50%. One patient required a second dose reduction for continued hyperphosphatemia.1

Illustration of a syringe

Injection site reaction

In the double-blind period of Study 4, approximately 12% of patients in both the CRYSVITA and placebo treatment groups had a local reaction (e.g., injection site reaction, erythema, rash, bruising, pain, pruritus, and hematoma) at the site of the injection. Injection site reactions were generally mild in severity, occurred within 1 day of injection, lasted approximately 1 to 3 days, required no treatment, and resolved in almost all instances.1

Illustration of a knee with waves radiating outward

Restless legs syndrome (RLS)

In the double-blind period of Study 4, approximately 12% of the CRYSVITA treatment group had worsening of baseline RLS or new onset RLS of mild to moderate severity; these events did not lead to dose discontinuation. Nonserious RLS has also been reported in other repeat-dose adult XLH studies; in 1 case, worsening baseline RLS led to drug discontinuation and subsequent resolution of the event.1

Illustration of 3 vertebra compressed tightly together

Spinal stenosis

Spinal stenosis is prevalent in adults with XLH, and spinal cord compression has been reported. In the CRYSVITA phase 2 and phase 3 studies of adults with XLH (N=176), a total of 7 patients underwent spinal surgery. Most of these cases appeared to involve progression of a preexisting spinal stenosis. It is unknown if CRYSVITA therapy exacerbates spinal stenosis or spinal cord compression.1

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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.

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COMM-US-CRY-0076 | March 2025