CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Sapropterin dihydrochloride (treatment of PKU and biopterin metabolic defects)

Policy governs medical coverage and authorization criteria for sapropterin dihydrochloride for members with phenylketonuria (PKU) or specified biopterin metabolic defects, including initial and reauthorization requirements and quantity limits.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicySapropterin dihydrochloride (treatment of PKU and biopterin metabolic defects)

Policy CodePolicy N/A

Change TypeNo material clinical or coverage changes

Effective DateDec 12, 2018

Next Review DateN/A

Key ActionObtain prior authorization and document baseline phenylalanine ≥ 360 μmol/L, patient age ≥ 1 month, specialty involvement, and response for reauthorization.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

1 monthminimum patient age for FDA-approved indication

>=360 μmol/Lbaseline Phe for initial PKU authorization

5-20 mg/kg/daypermitted dosing range

2 monthsinitial authorization duration (PKU)

6 monthsreauthorization duration

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Coverage Criteria

Initial Therapy - Phenylketonuria (PKU)

Covered when ALL of the following are met

PKU initial criteria: 1) Prescribed by, or in consultation with, a physician who specializes in metabolic disease and/or phenylketonuria (PKU); 2) Patient is 1 month of age or older; 3) Baseline phenylalanine (Phe) >= 360 μmol/L (6 mg/dL); 4) Therapy will be used in conjunction with a phenylalanine-restricted diet; 5) Member is not receiving sapropterin dihydrochloride in combination with Palynziq (pegvaliase-pqpz) or Sephience (sepiapterin); 6) Dose does not exceed 20 mg/kg/day (responsive patients may receive 5–20 mg/kg/day).dose <= 20 mg/kg/day

Initial authorization up to 2 months; if blood Phe does not decrease after one month, increase to 20 mg/kg/day and reassess; discontinue if no decrease after one month at 20 mg/kg/day.

Initial Therapy - Biopterin Metabolic Defects

Covered for specified biopterin metabolic defects when documentation is provided

Biopterin defects initial: Autosomal dominant guanine triphosphate cyclohydrolase deficiency (Segawa disease); Autosomal recessive guanine (GTP) cyclohydrolase deficiency; 6-pyruvoyl-tetrahydropterin synthase (6-PTS) deficiency; Sepiapterin reductase deficiency; Dihydropteridine reductase (DHPR) deficiency; Pterin-4a-carbinolamine dehydratase deficiency (primapterinuria).

Authorization up to 6 months.

Continuation Therapy - PKU

Covered when ALL of the following are met

PKU reauthorization: 1) Member continues to meet all initial PKU criteria; AND 2) Chart notes or medical records demonstrate either a 30% decrease in phenylalanine from baseline OR phenylalanine < 360 μmol/L OR improvement in neuropsychiatric symptoms.30% decrease OR Phe < 360 μmol/L

Authorization up to 6 months.

Continuation Therapy - Biopterin Metabolic Defects

Covered when ALL of the following are met

Biopterin defects reauthorization: Members with any listed biopterin metabolic defect requesting reauthorization must demonstrate benefit from therapy as evidenced by disease stability or disease improvement.

Authorization up to 6 months.

All indications for sapropterin dihydrochloride that are not FDA-approved indications or the compendial uses listed in this policy are considered experimental/investigational and are not medically necessary.

Use of sapropterin for indications other than the FDA-approved indication and the specific compendial uses enumerated in this policy is not medically necessary.

Coding and Clinical Thresholds

inv-07: Baseline phenylalanine — >= 360 μmol/L

Baseline phenylalanine level>= 360 μmol/L (6 mg/dL)

Evidence sourceDocumentation of baseline Phe required for initial PKU authorization

Associated age requirementMember must be >= 1 month of age

Use with dietMust be used in conjunction with a phenylalanine-restricted diet

inv-08: Response threshold for reauthorization — 30% decrease from baseline OR phenylalanine < 360 μmol/L

Reauthorization response threshold30% decrease in Phe from baseline OR phenylalanine < 360 μmol/L

Alternative evidence for benefit

Provider Actions and Prior Authorization

Prior Authorization

Prior Authorization Required

Prior authorization is required. Initial authorizations: up to 2 months for Phenylketonuria (PKU) when initial-therapy criteria are met; up to 6 months for members with documented biopterin metabolic defects. Reauthorization for continued PKU treatment may be granted for up to 6 months when continuation criteria are met (see reauthorization requirements).

Initial authorization: PKU — up to 2 months when prescribed by or in consultation with a metabolic/PKU specialist, member ≥1 month old, baseline Phe ≥360 μmol/L, used with a Phe-restricted diet, not used concurrently with Palynziq or Sephience, and dose ≤20 mg/kg/day.
Initial authorization: Biopterin metabolic defects — up to 6 months for documented defects (autosomal dominant GTP cyclohydrolase deficiency/Segawa disease; autosomal recessive GTP cyclohydrolase deficiency; 6-pyruvoyl-tetrahydropterin synthase deficiency).
Reauthorization (PKU): up to 6 months when member continues to meet initial criteria AND there is documentation of either a 30% reduction in Phe from baseline, Phe <360 μmol/L, or improvement in neuropsychiatric symptoms.

Prior Authorization

Dose Trial and Discontinuation

Follow a structured dose trial and stop strategy. Begin therapy within the approved dosing range (responsive patients may receive 5–20 mg/kg/day) and monitor blood phenylalanine (Phe) levels monthly during dose titration. If blood Phe does not decrease after one month at the current dose, escalate to 20 mg/kg/day. If there is no decrease after one month at 20 mg/kg/day, discontinue sapropterin dihydrochloride.

Background

Sapropterin is indicated to reduce blood phenylalanine (Phe) levels in patients with BH4-responsive phenylketonuria (PKU) and is used in conjunction with a phenylalanine-restricted diet. The FDA-approved population begins at 1 month of age. The medication is also listed for several biopterin metabolic defects as compendial uses, including guanine triphosphate cyclohydrolase deficiencies, 6-pyruvoyl-tetrahydropterin synthase deficiency, sepiapterin reductase deficiency, dihydropteridine reductase deficiency, and pterin-4a-carbinolamine dehydratase deficiency.

Definitions

inv-14: BH4-responsive PKU / Hyperphenylalaninemia (HPA) — Condition in which sapropterin reduces blood phenylalanine levels; FDA-approved indication for patients one month of age and older, used ...

DefinitionCondition in which sapropterin reduces blood phenylalanine levels; FDA‑approved indication for patients one month of age and older

Required concomitant therapyUsed in conjunction with a phenylalanine-restricted diet

Approved ageMinimum patient age: 1 month

Compendial/related conditionsIncludes several biopterin metabolic defects (e.g., GTP cyclohydrolase deficiencies, 6-PTS deficiency, sepiapterin reductase deficiency, DHPR deficiency, pterin-4a-carbinolamine dehydratase deficiency)