Strensiq (asfotase alfa) — Blue Cross Blue Shield of Kansas

Initial criteria

• The patient has a diagnosis of either perinatal/infantile- OR juvenile-onset hypophosphatasia (HPP) AND ALL of the following:
• A. Patient was less than 18 years of age at onset
• B. Patient is experiencing active disease (e.g., bone pain, fractures, gait problems)
• C. Patient has/had clinical manifestations consistent with hypophosphatasia prior to age 18 (e.g., vitamin B6-dependent seizures, fractures, lost teeth with roots, skeletal abnormalities such as rachitic chest deformity leading to respiratory problems or bowed arms/legs, or failure to thrive)
• D. Patient has/had radiographic imaging confirming the diagnosis of hypophosphatasia prior to age 18 (e.g., infantile rickets, alveolar bone loss, craniosynostosis)
• E. Molecular genetic testing confirming mutations in the ALPL gene that encodes the tissue nonspecific isoenzyme of ALP (TNSALP)
• F. Reduced activity of unfractionated serum alkaline phosphatase (ALP) below the normal lab reference range for age and sex, in the absence of bisphosphonate therapy
• G. ONE of the following: (1) Elevated serum pyridoxal 5'-phosphate (PLP) in absence of vitamin supplements within one week prior to test OR (2) Elevated urinary phosphoethanolamine (PEA) OR (3) Elevated urinary inorganic pyrophosphate (PPi)
• The prescriber is a specialist in the area of the patient’s diagnosis (e.g., endocrinologist, geneticist) or has consulted with a specialist
• The patient has had an ophthalmology examination and renal ultrasound at baseline (prior to therapy)
• The patient has no FDA-labeled contraindications to Strensiq
• The requested dose is within FDA-labeled dosing based on the patient’s weight

Reauthorization criteria

• The patient has been previously approved for Strensiq through the plan’s prior-authorization process
• Patient has had a decrease from baseline in at least ONE of the following: (A) Serum pyridoxal 5’-phosphate (PLP) in absence of vitamin supplements within one week prior to test OR (B) Urinary phosphoethanolamine (PEA) OR (C) Urinary inorganic pyrophosphate (PPi)
• Patient has had clinical improvement from baseline in at least ONE of the following: (A) Respiratory status OR (B) Growth OR (C) Radiographic findings
• The prescriber is a specialist in the area of the patient’s diagnosis (e.g., endocrinologist, geneticist) or has consulted with one
• Patient has been monitored for signs and symptoms of ophthalmic and renal calcifications and for changes in vision or renal function
• Patient does not have FDA-labeled contraindications to Strensiq

Approval duration

6 months