RetiredUnitedHealthcarePolicy CSLA2025D0071N

Crysvita (Burosumab-Twza) (for Louisiana Only)

Medical benefit drug policy governing coverage criteria for burosumab (Crysvita) for treatment of X-linked hypophosphatemia (XLH) and FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) for UnitedHealthcare Community Plan in Louisiana.

Policy Summary

PayerUnitedHealthcare

PolicyCrysvita (Burosumab-Twza) (for Louisiana Only)

Policy CodePolicy CSLA2025D0071N

Change TypeRetirement (LA membership) and routine review

Effective DateMay 1, 2025

Next Review DateN/A

Key ActionObtain prior authorization with documentation of diagnosis confirmation, required biochemical labs, specialist involvement, and dosing per FDA labeling.

SourceLink

POLICY UPDATE CHANGES

Retired policy; Louisiana plan membership disenrolled on Apr. 1, 2026.

Routine review; no change to coverage guidelines as of May 1, 2025.

Retired policy; Louisiana plan membership disenrolled on Apr. 1, 2026.

Routine review on 05/01/2025 with no change to coverage guidelines; archived previous policy version CSLA2024D0071M.

2FDA-indicated conditions covered (XLH, TIO)

≤12 moInitial authorization length

≤12 moReauthorization length

J0584

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Coverage Criteria for Crysvita (burosumab)

Initial Therapy (XLH)

Covered when ALL of the following are met for initial therapy (XLH):

XLH initial criteria: Diagnosis of X-linked hypophosphatemia (XLH) confirmed by genetic testing (e.g., confirmed PHEX gene mutation in the patient or a first-degree relative) OR elevated serum FGF23 > 30 pg/mL; AND biochemical findings: fasting serum phosphate < 3.0 mg/dL (0.97 mmol/L), serum creatinine below the age-adjusted upper limit of normal, and serum 25(OH)D ≥ 16 ng/mL; AND patient age ≥ 6 months; AND either open epiphyseal plate OR (epiphyseal plate fused AND presence of clinical signs/symptoms such as limited mobility, musculoskeletal pain, or bone fractures AND prior failure, contraindication, or intolerance to vitamin D analog therapy in combination with oral phosphate); AND prescribed by or in consultation with an endocrinologist or metabolic bone specialist; AND dosing per FDA-approved labeling; AND initial authorization limited to no more than 12 months.

Continuation Therapy (XLH)

Covered when ALL of the following are met for continuation:

XLH continuation criteria: Patient has previously received burosumab; AND prescribed by or in consultation with an endocrinologist or metabolic bone specialist; AND patient has experienced a positive clinical response to burosumab (e.g., enhanced height velocity, improvement in skeletal deformities, reduction of fractures, reduction of generalized bone pain); AND dosing per FDA-approved labeling; AND reauthorization limited to no more than 12 months.

Initial Therapy (TIO)

Covered when ALL of the following are met for initial therapy (TIO):

TIO initial criteria: Diagnosis of FGF23-related hypophosphatemia due to tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors; AND tumor cannot be curatively resected or localized; AND patient is age ≥ 2 years; AND prescribed by, or in consultation with, an oncologist, endocrinologist, or metabolic bone specialist; AND history of failure, contraindication, or intolerance to vitamin D analog therapy in combination with an oral phosphate agent; AND fasting serum phosphorus is below the normal range for age; AND dosing per FDA-approved labeling; AND initial authorization limited to no more than 12 months.

Continuation Therapy (TIO)

Covered when ALL of the following are met for continuation:

TIO continuation criteria: Patient has previously received burosumab; AND prescribed by, or in consultation with, an oncologist, endocrinologist, or metabolic bone specialist; AND patient has experienced a positive clinical response to burosumab (e.g., improvement in symptoms or biochemical markers); AND dosing per FDA-approved labeling; AND reauthorization limited to no more than 12 months.

The U.S. Food and Drug Administration (FDA) has approved Crysvita (burosumab) for two FGF23-mediated indications. For X-linked hypophosphatemia (XLH), the FDA indication covers adult and pediatric patients aged 6 months and older. For tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors that cannot be curatively resected or localized, the FDA indication covers adult and pediatric patients aged 2 years and older. These FDA age- and indication-specific approvals inform the policy’s scope but do not alone determine coverage decisions.

This policy was retired for UnitedHealthcare Community Plan membership in Louisiana; the retirement and disenrollment of Louisiana plan membership under this policy became effective on April 1, 2026.

Coverage under this policy is granted only when the patient meets all of the specific clinical criteria listed for the applicable indication (XLH or TIO). Required elements include documented diagnostic confirmation (genetic testing or elevated FGF23 for XLH; documentation that the tumor cannot be resected or localized for TIO), age consistent with the FDA-labeled indication, relevant biochemical findings (for example, fasting serum phosphorus below the normal range and for XLH initial therapy serum phosphate < 3.0 mg/dL (0.97 mmol/L)), specialist involvement, and dosing consistent with FDA labeling. Prior authorization is required and approvals (initial and reauthorization) are limited to up to 12 months when all criteria are satisfied.

Coding and Diagnostic References

Covered HCPCS CodesHCPCSCovered

J0584

Injection, burosumab-twza, 1 mg

Diagnosis Codes (reference)ICD-10

E83.31	Familial hypophosphatemia
M83.8	Other adult osteomalacia

Serum phosphate — XLH initial threshold

Serum phosphate threshold (XLH initial)Serum phosphate < 3.0 mg/dL (0.97 mmol/L)

ContextRequired as part of biochemical findings for initial burosumab therapy in XLH (along with SCr below age‑adjusted ULN and 25(OH)D ≥ 16 ng/mL)

Measurement timingFasting serum phosphorus is specified elsewhere for monitoring; the initial XLH criterion uses a serum phosphate < 3.0 mg/dL

Provider Requirements and Prior Authorization

Prior Authorization

Prior Authorization Required

Prior authorization required. Documentation must include the indication, diagnostic confirmation (genetic testing or elevated FGF23), age, specialist involvement, and required biochemical data (including fasting serum phosphate, serum phosphate, serum creatinine, and serum 25(OH)D). Lack of the required diagnostic confirmation or missing required biochemical data may result in denial.

Affected drug: burosumab (Crysvita) — HCPCS J0584
Diagnostic confirmation: genetic testing (PHEX mutation) OR elevated FGF23 (> 30 pg/mL)
Biochemical labs: serum phosphate (< 3.0 mg/dL for XLH) and fasting serum phosphorus below age normal for TIO; serum creatinine below age-adjusted ULN; serum 25(OH)D ≥ 16 ng/mL

Denial Risk

TIO — Documentation and Denial Risk

For tumor-induced osteomalacia (TIO), prior authorization must document that the phosphaturic tumor cannot be curatively resected or localized, the patient is ≥ 2 years old, and there is prior failure, contraindication, or intolerance to vitamin D analog therapy in combination with oral phosphate. Failure to document the tumor unresectability/localization or absence of prior vitamin D analog plus phosphate failure/contraindication/intolerance places the request at high risk for denial.

Background

X-linked hypophosphatemia (XLH) is a heritable disorder of renal phosphate transport caused by excess fibroblast growth factor 23 (FGF23), resulting in hypophosphatemia and impaired bone mineralization. Elevated FGF23 reduces renal tubular phosphate reabsorption and lowers serum phosphate, producing rickets in children and osteomalacia, bone pain, fractures, and impaired growth. Burosumab (Crysvita) is a monoclonal antibody that binds and inhibits excess FGF23 activity, restoring phosphate homeostasis and improving clinical and radiographic outcomes in affected patients. Tumor-induced osteomalacia (TIO) is an acquired, FGF23-mediated paraneoplastic syndrome caused by phosphaturic mesenchymal tumors that secrete FGF23; when those tumors cannot be localized or curatively resected, medical therapy with an FGF23-blocking agent may be indicated.

Definitions

XLH — definition and key features

DefinitionX-linked hypophosphatemia (XLH) is a heritable disorder of renal phosphate transport characterized by elevated FGF23 and resulting hypophosphatemia and abnormal bone mineralization.

Biochemical thresholdSerum phosphate < 3.0 mg/dL (0.97 mmol/L) is a defined biochemical finding for initial therapy in XLH.

Clinical featuresClinical manifestations include rickets/osteomalacia in children, skeletal deformities, bone pain, fractures, and impaired growth; treatment goals differ by age and epiphyseal status.

TIO — definition and relation to FGF23-producing tumors

DefinitionTumor-induced osteomalacia (TIO) is a rare acquired paraneoplastic syndrome in which typically benign phosphaturic mesenchymal tumors ectopically secrete FGF23, producing FGF23-related hypophosphatemia and bone mineralization abnormalities similar to genetic forms of hypophosphatemic rickets.

Policy History

2026-04-01retirementLatest

Policy retired for Louisiana plan membership; Louisiana membership disenrolled effective Apr 1, 2026.

2025-05-01routine_review

Routine review completed with no change to coverage guidelines; previous policy version CSLA2024D0071M archived.