CurrentBlue Cross Blue Shield - IowaPolicy 05.02.46

Crysvita (burosumab-twza) coverage criteria for X-linked hypophosphatemia and tumor-induced osteomalacia

Criteria and prior authorization requirements for coverage of Crysvita (burosumab-twza) for treatment of X-linked hypophosphatemia (XLH) in patients ≥6 months and FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) in patients ≥2 years within Wellmark/Blue Cross Blue Shield plans.

Policy Summary

PayerBlue Cross Blue Shield - Iowa

PolicyCrysvita (burosumab-twza) coverage criteria for X-linked hypophosphatemia and tumor-induced osteomalacia

Policy CodePolicy 05.02.46

Change TypeReview (no material clinical changes)

Effective DateMay 28, 2021

Next Review Date

Key ActionSubmit prior authorization with required diagnostic and laboratory documentation (genetic testing or FGF23 level, serum phosphorus, creatinine clearance, imaging or venous sampling for TIO) to support initial or continuation requests.

SourceLink

POLICY UPDATE CHANGES

Policy reviewed January 2026; prior revision noted April 2021.

≥6 moMinimum age for XLH indication

≥2 yrMinimum age for TIO indication

CrCl ≥30Creatinine clearance requirement

12 moApproval duration for initial therapy

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

J0584Billing HCPCS code

Coverage Criteria

Initial Therapy — X-linked hypophosphatemia

Covered when ALL of the following are met

Initial XLH criteria: 1. Diagnosis of X-linked hypophosphatemia confirmed by one of: A) genetic testing confirming a PHEX mutation in the member; B) genetic testing confirming a PHEX mutation in a directly related family member with appropriate X-linked inheritance; OR C) FGF23 level > 30 pg/mL; 2. Diagnosis made by, or in consultation with, a specialist experienced in metabolic bone disorders (Endocrinologist, Nephrologist, Rheumatologist, or Orthopedist); 3. Serum phosphorus below the normal range for age; 4. Creatinine clearance (CrCl) ≥ 30 mL/min; 5. Presence of clinical signs and/or symptoms of disease (e.g., rickets, growth retardation, musculoskeletal pain, bone fractures).

Initial approval per source chunk 7

Initial Therapy — Tumor-Induced Osteomalacia

Covered when ALL of the following are met

Initial TIO criteria: 1. Diagnosis of tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors confirmed by one of: A) functional imaging (FDG-PET/CT AND Octreoscan/CT); B) anatomical imaging (MRI AND/OR CT); OR C) venous sampling; 2. Diagnosis made by, or in consultation with, an Oncologist or a specialist experienced in metabolic bone disorders (Endocrinologist, Nephrologist, Rheumatologist, or Orthopedist); 3. Serum FGF23 level > 100 pg/mL; 4. Serum phosphorus below the normal range for age; 5. Creatinine clearance (CrCl) ≥ 30 mL/min; 6. Presence of clinical signs and/or symptoms of disease (e.g., rickets, growth retardation, musculoskeletal pain, bone fractures); 7. Tumors cannot be curatively resected or localized; 8. TmP/GFR below the normal range for age.

Initial approval per source chunk 8

Continuation Therapy

Covered when ALL of the following are met

Continuation criteria: 1. Patient meets criteria for initial approval for diagnosis and prescriber specialty; 2. (TIO only) Tumors cannot be curatively resected or localized; 3. Improvement in serum phosphorus while on therapy; 4. Clinical improvement and/or stabilization documented (e.g., enhanced height velocity, improvement in skeletal deformities, reduction of fractures, reduction of generalized bone pain, or enhanced mobility); 5. Creatinine clearance (CrCl) ≥ 30 mL/min.

Continuation requirements per source chunk 9

This policy is subject to the terms of the members benefit contract. Exclusions, limitations, or exceptions may apply and benefits can vary by contract. Individual member benefits should be verified prior to service. This medical policy may not apply to Federal Employee Program (FEP) members; benefit determinations for FEP are made by the Federal Employee Program.

Coding and Laboratory Criteria

Covered HCPCS CodesHCPCSCovered

J0584

Injection, burosumab-twza 1 mg

inv-06: FGF23 level — XLH and TIO thresholds

FGF23 threshold — XLHFGF23 level > 30 pg/mL

FGF23 threshold — TIOFGF23 level > 100 pg/mL

PurposeDiagnostic criterion to confirm FGF23-mediated hypophosphatemia for coverage

inv-07: Serum phosphorus — below normal range for age requirement

Serum phosphorus requirementSerum phosphorus below the normal range for age (required for both XLH and TIO)

When requiredRequired for initial and continuation requests per disease-specific criteria

Provider Actions and Authorization Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for requests for Crysvita (burosumab-twza). Providers must submit supporting clinical documentation for both initial and continuation therapy to initiate prior authorization review.

Prior authorization required for Crysvita (burosumab-twza)
Approval duration: 12 months (when approved)

Documentation Required

Required Documentation for Prior Authorization

For initial prior authorization requests, submit documentation confirming the diagnosis and baseline laboratory and clinical data. For continuation requests, submit documentation demonstrating clinical benefit and relevant follow-up labs. Failure to provide required documentation may result in denial or delay of the request.

Initial and continuation requests require submission of relevant medical records and laboratory data

Background

Burosumab (Crysvita) is a human monoclonal antibody that targets FGF23. It is indicated for the treatment of X-linked hypophosphatemia (XLH) in adults and pediatric patients 6 months and older, and for the treatment of FGF23-related hypophosphatemia in tumor-induced osteomalacia (TIO) in patients 2 years and older. Coverage under this policy aligns with these FDA-approved indications and requires diagnostic confirmation and specialist involvement for initiation and continuation of therapy.

Definitions

inv-15: X-linked hypophosphatemia (XLH) definition

DefinitionX-linked hypophosphatemia (XLH) is a phosphate-wasting genetic disorder often associated with PHEX mutations and elevated FGF23.

Age indicationFDA indication: XLH in adult and pediatric patients 6 months of age or older.

Diagnostic confirmationDiagnosis may be confirmed by genetic testing for a PHEX mutation or elevated FGF23 (>30 pg/mL) per policy criteria.

inv-16: Tumor-induced osteomalacia (TIO) definition

DefinitionTumor-induced osteomalacia (TIO) is FGF23-related hypophosphatemia caused by phosphaturic mesenchymal tumors that cannot be curatively resected or localized.

Age indicationFDA indication: TIO in adult and pediatric patients 2 years of age and older.

Revision History

2026-01reviewLatest

Policy reviewed (no material clinical changes noted).

2021-04revision

Policy revised (prior revision recorded).

2021-05-28effective_date

Current policy effective date established.

Policy Summary

PayerBlue Cross Blue Shield - Iowa

PolicyCrysvita (burosumab-twza) coverage criteria for X-linked hypophosphatemia and tumor-induced osteomalacia

Policy CodePolicy 05.02.46

Change TypeReview (no material clinical changes)

Effective DateMay 28, 2021

Next Review Date

SourceLink

On This Page

PurposeConfirms biochemical hypophosphatemia alongside other diagnostic testing

inv-08: TmP/GFR — below normal range for age (TIO)

TmP/GFR requirementTmP/GFR (tubular reabsorption of phosphate/ GFR) below the normal range for age (required for TIO)

When requestedRequired as part of initial documentation for TIO to demonstrate renal phosphate wasting

SourceSpecified in TIO initial criteria and prior authorization submission requirements

inv-09: Creatinine clearance requirement

Creatinine clearance thresholdCreatinine clearance (CrCl) ≥ 30 mL/min

Applies toRequired for initial and continuation eligibility for both XLH and TIO

PurposeEnsures adequate renal function for safe use and monitoring of therapy

Missing or incomplete documentation may result in denial or delay of coverage

Documentation Required

Indication-Specific Supporting Documents

Required documentation varies by indication. Provide the items listed below as applicable to X-linked hypophosphatemia (XLH) or tumor-induced osteomalacia (TIO).

X-linked hypophosphatemia — Initial requests: genetic testing results confirming a PHEX mutation in the member or a directly related family member with appropriate X-linked inheritance; serum FGF23 level (if applicable); medical records documenting clinical findings and radiographic features supporting XLH; serum phosphorus levels; creatinine clearance.
X-linked hypophosphatemia — Continuation requests: medical records documenting clinical benefit; serum FGF23 level (if applicable); serum phosphorus levels; creatinine clearance.
Tumor-induced osteomalacia — Initial requests: serum FGF23 level; medical records documenting clinical findings and radiographic features supporting FGF23-related hypophosphatemia in TIO; medical records documenting TmP/GFR (ratio of renal tubular reabsorption of phosphate to GFR); serum phosphorus levels; creatinine clearance; imaging/diagnostic evidence as applicable to localize or attempt to localize phosphaturic mesenchymal tumors.
Tumor-induced osteomalacia — Continuation requests: medical records documenting clinical benefit; serum FGF23 level; serum phosphorus level; creatinine clearance.

Prior Authorization

Age, Dosing, and Prescriber Requirements

Approvals may be subject to age and dosing limits consistent with FDA-approved labeling, accepted compendia, and evidence-based practice guidelines. Include prescriber specialty and patient age as part of the submission.

Age limits: XLH — patients 6 months of age and older; TIO — patients 2 years of age and older (per clinical criteria).
Prescriber specialty: diagnosis must be made by or in consultation with an appropriate specialist (Endocrinologist, Nephrologist, Rheumatologist, Orthopedist, or Oncologist for TIO).

Denial Risk

Missing Documentation — Consequences & Common Omissions

If required documentation is missing or incomplete, the prior authorization request may be denied or returned for additional information. To prevent delays, include all applicable genetic testing, FGF23 levels, serum phosphorus, creatinine clearance, imaging and clinical/radiographic records demonstrating diagnosis and treatment response.

Common missing items: genetic test results (PHEX), FGF23 levels, TmP/GFR, serum phosphorus, creatinine clearance, specialist consult notes, radiographic evidence, documentation of clinical benefit for renewals.
Consequence: incomplete submissions may be denied or delayed pending receipt of required records.

Diagnostic confirmationDiagnosis requires tumor localization by functional/anatomical imaging or venous sampling, elevated FGF23 (>100 pg/mL), and TmP/GFR below age-normal range per policy criteria.