New prior authorization requirements for Burosumab-Twza(Crysvita)

Attention: Nephrologists and Endocrinologists Effective Date: 1/6/2021 Call to action: Texas Children’s Health Plan (TCHP) is aligning prior authorization criteria for burosumab-twza (Crysvita), J0584, with the Texas Medicaid Provider Procedures Manual (TMPPM). Crysvita is a clinician administered drug indicated for members with X-linked hypophosphatemia (XLH) and Fibroblast Growth Factor 23 (FGF23)-related hypophosphatemia. Below are the new prior authorization criteria for TCHP members effective 01/06/2021. For initial therapy, the following criteria must be met:

• The client has a diagnosis of X-linked hypophosphatemia (XLH) (diagnosis code E8330 or E8331) that is supported by one of the following:
  • Confirmed phosphate regulating gene with homology to endopeptidases located on the X chromosome (PHEX-gene) mutation
  • Serum fibroblast growth factor-23 (FGF23) level >30 pg/ml
• The client is six months of age or older
• The prescriber discontinues any oral phosphate or active vitamin D analog supplementation at least one week prior to starting burosumab-twza (Crysvita) therapy.
• The prescriber agrees to measure serum phosphate throughout therapy and withhold medication when serum phosphorus is above 5 mg/dl.

OR

• The client has a diagnosis of fibroblast growth factor 23 (FGF23)-related hypophosphatemia in tumor-induced osteomalacia associated with phosphaturic mesenchymal tumors that cannot be localized or are not amenable to surgical excision.
• The client is two years of age or older.
• The prescriber discontinues any oral phosphate or vitamin D analog supplement at least two weeks prior to starting burosumab-twza (Crysvita) therapy.
• The prescriber agrees to measure serum phosphate throughout therapy.

For both indications: For renewal or continuation of therapy, the following criteria must be met:

• Previous treatment of Burosumab-twza (Crysvita)
• Provider continues to monitor serum phosphate level
• Documentation from the provider that:

• Patient has achieved normal levels of phosphate OR
• Patient has demonstrated positive clinical response to Burosumab-twza (Crysvita) (e.g., enhanced height velocity, improvement in askeletal deformity, reduction of fractures, and reduction of generalized bone pain)

How this impacts providers: Prescribers should adjust their prescribing patterns accordingly and communicate these changes to their staff. Next steps for providers: Providers should communicate these changes to their staff. If you have any questions, please email Provider Network Management at: providerrelations@texaschildrens.org.For access to all provider alerts,log into: www.thecheckup.org or www.texaschildrenshealthplan.org/for-providers.