CurrentNeighborhood Health Plan of Rhode IslandPolicy nitisinone-Nityr-Orfadin 2120-A SGM P2023.docx

Nitisinone (Nityr, Orfadin) — Coverage Criteria for Hereditary Tyrosinemia Type 1

Covers prior authorization criteria and documentation requirements for nitisinone products (Nityr, Orfadin) for treatment of hereditary tyrosinemia type 1 (HT-1) for members of Neighborhood Health Plan of Rhode Island.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyNitisinone (Nityr, Orfadin) — Coverage Criteria for Hereditary Tyrosinemia Type 1

Policy CodePolicy nitisinone-Nityr-Orfadin 2120-A SGM P2023.docx

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionSubmit biochemical testing, enzyme assay, or genetic testing results supporting the diagnosis to initiate prior authorization review.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

12 monthsauthorization duration (initial and continuation)

2FDA‑approved product names listed

1required documentation types listed

Coverage Criteria for Nitisinone (Nityr, Orfadin)

inv-01: Initial Approval

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inv-02: Continuation of Therapy

Covered when ALL of the following are met for continuation:

Continuation criteria: Member is experiencing a beneficial clinical response from nitisinone therapy for hereditary tyrosinemia type 1 (HT-1).

Authorization may be granted for 12 months upon reauthorization.

inv-11: Confirmation of hereditary tyrosinemia type 1 (HT-1) to support nitisinone therapy — DNA testing/diagnostic confirmation criteria

Diagnostic confirmation to support nitisinone therapy: Genetic (DNA) testing OR biochemical testing (e.g., detection of succinylacetone in urine) confirming HT-1 is provided to support initiation of nitisinone therapy.

Used to confirm diagnosis for coverage of nitisinone; nitisinone is indicated only for HT-1 in combination with dietary restriction of tyrosine and phenylalanine.

Provider Actions and Authorization Requirements

Prior Authorization

Prior authorization may be granted for 12 months

Prior authorization is required; if coverage criteria are met, an authorization of 12 months may be granted for both initial and continued treatment.

Step Therapy

Adjunct to dietary tyrosine/phenylalanine restriction

Therapy must be used as an adjunct to dietary restriction of tyrosine and phenylalanine as part of treatment for hereditary tyrosinemia type 1.

Documentation Required

Provide diagnostic test results with prior authorization request

Submit biochemical testing, enzyme assay, or genetic (DNA) testing results that support the diagnosis to initiate prior authorization review.

Examples include detection of succinylacetone in urine (biochemical) or DNA testing confirming HT‑1.

Denial Risk

Non‑HT‑1 indications are not covered

Use of nitisinone for indications other than hereditary tyrosinemia type 1 is considered experimental/investigational and not medically necessary and may be denied.

Covered Indications

inv-11: Confirmation of hereditary tyrosinemia type 1 (HT-1) to support nitisinone therapy — DNA testing can be used to confirm diagnosis for coverage of nitisinone.

Role of DNA testing: DNA testing may be used to confirm a diagnosis of hereditary tyrosinemia type 1 (HT-1) for purposes of meeting coverage criteria for nitisinone therapy.

Confirmation can also be by biochemical testing (e.g., succinylacetone in urine); nitisinone coverage is limited to HT-1 when used with dietary restriction of tyrosine and phenylalanine.

Definitions and Diagnostic Confirmation

Diagnostic confirmation

Required diagnostic methodsConfirmation by biochemical testing (e.g., detection of succinylacetone in urine), enzyme assay, or DNA testing is required to authorize therapy.

Example biochemical testDetection of succinylacetone in urine.

Genetic confirmationDNA testing can be used to confirm diagnosis of hereditary tyrosinemia type 1 (HT-1) to support coverage.

Role of enzyme assayEnzyme assay may be used as an alternative method to confirm diagnosis.

Connection to treatment authorizationDiagnosis confirmation by one of these methods is required before nitisinone therapy is authorized.

Background

Hereditary tyrosinemia type 1 (HT‑1) is treated with nitisinone (Nityr, Orfadin) in combination with dietary restriction of tyrosine and phenylalanine. The policy covers FDA‑approved uses for adult and pediatric patients when diagnostic confirmation is provided; diagnostic confirmation may include biochemical testing (for example, detection of succinylacetone in urine) or DNA testing. Prior authorization may be granted for up to 12 months when criteria are met.