Neighborhood Health Plan RI Crysvita Coverage Update

Coverage Criteria for Crysvita (burosumab-twza)

Initial Therapy — XLH

Covered when ALL of the following are met

XLH initial criteria: 1) Diagnosis of X-linked hypophosphatemia (XLH) confirmed by at least one of the following: an elevated serum FGF23 per thresholds (FGF23 > 30 pg/mL; 7230 RU/mL in children 3 months-17 years; >180 RU/mL in adults using EDTA plasma) OR a pathogenic PHEX gene mutation; 2) Member is at least 6 months of age; 3) For adult patients: documentation of inadequate response to oral phosphate and active vitamin D analogs; 4) Baseline fasting serum phosphorus demonstrating hypophosphatemia (phosphate below the lower limit of the laboratory reference range); 5) Dosing consistent with weight and age: pediatric <10 kg starting 1 mg/kg every 2 weeks (rounded to nearest mg) not to exceed product limits; pediatric >=10 kg starting 0.8 mg/kg every 2 weeks (rounded) up to 90 mg; adults starting 1 mg/kg every 4 weeks (rounded) up to 90 mg — member weight and requested dose must be provided; 6) Not used concomitantly with oral phosphate and/or active vitamin D analogs; 7) Other causes of hypophosphatemia (e.g., autosomal dominant or recessive hypophosphatemic rickets) have been ruled out; 8) 25-hydroxy vitamin D levels will be monitored at baseline and intermittently and supplemented to the normal range for age when indicated.see thresholds

6-month initial authorization

Initial Therapy — TIO

Covered when ALL of the following are met

TIO initial criteria: 1) Prescribed by, or in consultation with, a nephrologist or endocrinologist; 2) Diagnosis of tumor-induced osteomalacia (TIO) associated with a phosphaturic mesenchymal tumor that cannot be curatively resected or localized; 3) Diagnosis confirmed by excessive FGF23 (e.g., ≥100 pg/mL); 4) Patient is at least 2 years of age; 5) Baseline fasting serum phosphorus demonstrating hypophosphatemia (phosphate below the lower limit of the laboratory reference range); 6) Reduced tubular reabsorption of phosphate corrected for GFR (TmP/GFR) consistent with renal phosphate wasting; 7) Not used concomitantly with oral phosphate and/or active vitamin D analogs; 8) No severe renal impairment (defined as GFR < 30 mL/min excludes therapy; GFR must be ≥ 30 mL/min to qualify); 9) Dosing: pediatric starting dose 0.4 mg/kg every 2 weeks (rounded) up to a maximum of 180 mg; adult starting dose 0.5 mg/kg every 2 weeks (rounded) up to a maximum of 180 mg — member weight and requested dose must be provided.see thresholds

6-month initial authorization

Continuation Therapy

Covered when ALL of the following are met

Continuation of therapy: 1) Patient continues to meet universal and indication-specific criteria as identified for the initial authorization; 2) Absence of unacceptable toxicity (examples include severe hypersensitivity reactions, hyperphosphatemia and/or nephrocalcinosis, severe injection site reactions); 3) Current serum phosphorus level is not above the upper limit of the laboratory normal reference range; 4) Evidence of disease response such as increased serum phosphorus, reduction in serum total alkaline phosphatase activity, improvement in symptoms (e.g., skeletal pain, linear growth), and/or radiographic improvement of rickets/osteomalacia; 5) Pediatric patients should be re-evaluated at adulthood or upon epiphyseal closure to determine continued need for therapy; 6) For TIO patients who undergo curative treatment of the underlying tumor (surgical excision or radiation), interrupt therapy and reassess serum phosphorus after treatment completion.see monitoring notes

12-month authorization possible

Requests for Crysvita (burosumab-twza) will be denied if the patient is receiving concomitant oral phosphate and/or active vitamin D analogs (examples include calcitriol, paricalcitol, doxercalciferol, calcifediol). The policy requires that Crysvita not be used at the same time as these agents for both X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO).

Tumor-induced osteomalacia (TIO) is excluded from treatment with Crysvita when the patient has severe renal impairment defined as a glomerular filtration rate (GFR) < 30 mL/min. This renal function threshold must be met to consider burosumab for TIO.

Coverage is limited to the labeled indications of X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO) that meet the policy’s specific diagnostic and laboratory criteria. Use of Crysvita for other diagnoses, or when the required confirmatory tests (for example, appropriate FGF23 levels, PHEX mutation when applicable, baseline fasting hypophosphatemia, and TmP/GFR) are not provided, is considered not medically necessary and is not supported by this policy.

Coding and Test Thresholds

HCPCS codeHCPCS

J0584

Injection, burosumab-twza, 1 mg

Billing unit guidancemixed

90 billable units every 14 days (pediatrics)
90 billable units every 28 days (adults)
180 billable units every 14 days

inv-09: FGF23 level for diagnosis — thresholds for XLH and TIO

XLH — diagnostic FGF23 thresholdSerum FGF23 > 30 pg/mL (children 3 months–17 years: 7230 RU/mL; adults: >180 RU/mL in EDTA plasma)

XLH — alternative diagnostic evidencePresence of PHEX gene mutation supports diagnosis

TIO — diagnostic FGF23 thresholdExcessive FGF23 (e.g., ≥100 pg/mL) supports diagnosis of tumor‑induced osteomalacia

inv-10: Renal function threshold — Severe renal impairment defined as GFR < 30 mL/min excludes TIO treatment

Renal function exclusion for TIOSevere renal impairment defined as glomerular filtration rate (GFR) < 30 mL/min excludes TIO treatment

Monitoring requirement

Prior Authorization, Documentation, and Denial Triggers

Prior Authorization

Prior Authorization Required

Prior authorization required. Initial approvals are typically granted for 6 months when all indication‑specific criteria are met. Continuation approvals and duration are described in the Continuation of Therapy section (authorization may be extended up to 12 months when continuation criteria are met).

Initial authorization: up to 6 months when all criteria for the requested indication are documented
Continuation authorization: up to 12 months when continuation criteria are met and no unacceptable toxicity is present

Step Therapy

Step Requirement for Adults with XLH

For adults with X‑linked hypophosphatemia (XLH), documentation must show inadequate clinical response to conventional therapy with oral phosphate and active vitamin D analogs prior to approval.

Background on Burosumab (Crysvita)

Burosumab (Crysvita) is a monoclonal antibody that targets and inhibits fibroblast growth factor-23 (FGF23). It is indicated for treatment of X-linked hypophosphatemia (XLH) and tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors not amenable to curative resection. Clinical studies have shown that treatment with burosumab can increase and, in some patients, normalize serum phosphorus levels and lead to improvements in biochemical markers and clinical outcomes such as bone lesion healing and symptom reduction. Common adverse reactions reported include tooth abscess, muscle spasms, dizziness, constipation, injection site reactions, rash, and headaches.

Definitions

inv-17: XLH — X-linked hypophosphatemia (XLH)

DefinitionX-linked hypophosphatemia (XLH)

Typical age indicationIndication includes adults and pediatric patients 6 months of age and older

Diagnostic criteria summaryDiagnosis confirmed by elevated FGF23 per thresholds or PHEX gene mutation; baseline hypophosphatemia required

inv-18: TIO — Tumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors not amenable to curative resection

DefinitionTumor-induced osteomalacia (TIO) associated with phosphaturic mesenchymal tumors not amenable to curative resection

Diagnostic confirmationDiagnosis confirmed by excessive FGF23 (e.g., ≥100 pg/mL) and reduced TmP/GFR with hypophosphatemia

OpenPayer

Crysvita (burosumab-twza) — Clinical Coverage Criteria for XLH and TIO

Coverage Criteria for Crysvita (burosumab-twza)

Coding and Test Thresholds

Prior Authorization, Documentation, and Denial Triggers

Background on Burosumab (Crysvita)

Definitions