CurrentNeighborhood Health Plan of Rhode IslandPolicy 2120-A

nitisinone (Nityr, Orfadin, Harliku) prior authorization and coverage

Defines coverage, prior authorization requirements, and clinical criteria for nitisinone products (Nityr, Orfadin, Harliku) for treatment of hereditary tyrosinemia type 1 and alkaptonuria for members when approval criteria are met.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

Policynitisinone (Nityr, Orfadin, Harliku) prior authorization and coverage

Policy CodePolicy 2120-A

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionSubmit biochemical, enzyme assay, or genetic testing results to confirm diagnosis when requesting prior authorization.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

12 monthstypical authorization period

2covered labeled indications

3products referenced

specialistprescriber requirement

Coverage Criteria for Nitisinone Products

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HT-1 initial therapy criteria: 1) Diagnosis of hereditary tyrosinemia type 1 (HT-1) confirmed by biochemical testing (e.g., detection of succinylacetone in urine), enzyme assay, or genetic testing; 2) Requested medication is nitisinone (generic), Nityr, or Orfadin; 3) Medication is used as an adjunct to dietary restriction of tyrosine and phenylalanine.

Authorization duration: 12 months.

inv-02: Alkaptonuria (AKU) — Initial Authorization (Harliku only)

Authorization of 12 months may be granted for AKU when ALL of the following are met:

AKU initial therapy criteria (Harliku only): 1) Member is 18 years of age or older; 2) Diagnosis of alkaptonuria (AKU) confirmed by biochemical testing (e.g., detection of increased levels of homogentisic acid (HGA) in urine), enzyme assay, or genetic testing; 3) Requested medication is Harliku.

Authorization duration: 12 months; other indications considered experimental/investigational and not medically necessary.

inv-03: Continuation of Therapy

Authorization of 12 months may be granted for continued treatment when ALL of the following are met:

Continuation of therapy: 1) Member requests reauthorization for an indication listed in the coverage criteria; 2) Member is experiencing beneficial clinical response from therapy.

Authorization duration: 12 months.

All indications for nitisinone products that are not explicitly listed in this policy are considered experimental/investigational and not medically necessary. Coverage is limited to the specific, approved indications described in the criteria sets (e.g., hereditary tyrosinemia type 1 and alkaptonuria for the products and populations specified).

Use of Harliku or other nitisinone products for indications other than those explicitly listed in this policy is considered experimental/investigational and not medically necessary. Harliku is indicated for reduction of urine homogentisic acid (HGA) in adults with alkaptonuria (AKU); it and other nitisinone formulations are not covered for off‑label uses outside the approved indications described here.

Prior Authorization, Documentation, and Step Therapy

Prior Authorization

Prior Authorization Requirement

Authorization of 12 months may be granted when coverage criteria are met for the listed indications (e.g., HT-1 for nitisinone products; AKU for Harliku). Prior authorization is required for initiation and continuation of therapy.

Authorization may be granted for up to 12 months for initial and continuation therapy when criteria are met.
Prior authorization required for nitisinone products and Harliku for the indicated diagnoses.

Step Therapy

No step therapy requirements are specified in this document.

Documentation Required

Required Diagnostic Documentation

Submission of diagnostic documentation is required to initiate prior authorization review. Acceptable documentation includes biochemical testing, enzyme assay, or genetic testing results supporting the diagnosis (for example: detection of succinylacetone in urine for HT-1; increased homogentisic acid (HGA) in urine for AKU).

Required: biochemical testing, enzyme assay, or genetic testing results supporting the diagnosis.
Examples: succinylacetone in urine for HT-1; increased HGA in urine for AKU.

Denial Risk

Missing Diagnostic Documentation

If diagnostic documentation (biochemical testing, enzyme assay, or genetic testing results) supporting the diagnosis is not submitted, prior authorization cannot be initiated and the request may be denied.

Lack of required diagnostic documentation will prevent initiation of prior authorization and may result in denial.

Key Definitions

HT-1 definition — Hereditary tyrosinemia type 1 (HT-1)

DefinitionHereditary tyrosinemia type 1 (HT-1): a metabolic disorder treated with nitisinone (Nityr/Orfadin or generic) in combination with dietary restriction of tyrosine and phenylalanine.

Diagnostic confirmation requiredDiagnosis must be confirmed by biochemical testing (e.g., detection of succinylacetone in urine), enzyme assay, or genetic testing.

Therapeutic roleNitisinone is used as adjunct therapy alongside dietary restriction of tyrosine and phenylalanine.

AKU definition — Alkaptonuria (AKU)

DefinitionAlkaptonuria (AKU): a rare metabolic disorder characterized by elevated homogentisic acid (HGA).

Indicated productHarliku is indicated to reduce urine homogentisic acid (HGA) in adult patients with AKU.

Diagnostic confirmation requiredDiagnosis must be confirmed by biochemical testing, enzyme assay, or genetic testing.

Background on Nitisinone and Indications

Nitisinone products are indicated for specific metabolic disorders and coverage is restricted to those labeled uses. Specifically, Harliku is indicated for reduction of urine homogentisic acid (HGA) in adults with alkaptonuria (AKU). The policy requires that use be for an approved indication; any other uses are considered experimental/investigational and not medically necessary.