CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Nitisinone (Orfadin, Nityr) for hereditary tyrosinemia type 1

Covers authorization criteria for nitisinone formulations (Orfadin, Nityr, generic) for treatment of hereditary tyrosinemia type 1 (HT-1) for Medicaid members when approval criteria are met.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyNitisinone (Orfadin, Nityr) for hereditary tyrosinemia type 1

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateJun 20, 2019

Next Review DateN/A

Key ActionObtain prior authorization with documentation of diagnostic confirmation (biochemical, enzyme assay, or genetic testing) and required step-therapy documentation for brand products.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 moauthorization duration for initial and continuation approvals

HT-1covered indication (hereditary tyrosinemia type 1)

generic firstrequirement to document failure/intolerance to generic nitisinone before brand products

biochemical/enzyme/geneticdiagnostic confirmation methods

Medicaid

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Coverage Criteria for Nitisinone (Orfadin, Nityr, generic)

Initial Approval

Covered when ALL of the following are met

Initial Approval for HT-1: 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 nitisinone medication is being used as an adjunct to dietary restriction of tyrosine and phenylalanine; 3) If brand Nityr (nitisinone) tablets are requested, documentation of failure or intolerance to generic nitisinone capsules is provided; 4) If brand Orfadin (nitisinone) suspension is requested, documentation of failure or intolerance to generic nitisinone capsules AND to Nityr (nitisinone) tablets is provided; 5) If oral suspension is requested, documentation that the member is unable to tolerate/swallow the oral tablet AND capsuleauthorization 6 months

Authorization of 6 months may be granted

Continuation of Therapy

Covered when ALL of the following are met

Continuation of Therapy: 1) Member continues to meet all initial authorization criteria for HT-1 treatment; 2) Member shows evidence of positive clinical response (e.g., decrease in urinary/plasma succinylacetone and alpha-1-microglobulin levels) while on therapyauthorization 6 months

Authorization of 6 months for continuation

All indications for nitisinone other than treatment of hereditary tyrosinemia type 1 (HT-1) are considered experimental/investigational and are not covered.

Diagnostic confirmation acceptable

Diagnostic confirmation via genetic testing: Diagnostic confirmation of hereditary tyrosinemia type 1 (HT-1) by genetic testing is acceptable to meet the initial approval requirement for diagnosis; biochemical testing (e.g., succinylacetone) or enzyme assay are also acceptable methods

Authorization Duration and Coding Notes

Authorization duration

Authorization duration6 months

Policy effective/review datesEffective 6/2019; revised 10/2019, 06/2020; reviewed through 3/2025

ScopeMedicaid

Provider Requirements and Prior Authorization Actions

Prior Authorization

Prior Authorization Required

Prior authorization is required for coverage and is approved for up to 6 months.

Duration: Authorization of 6 months for initial and continuation approvals.
PA applies when medication is used as adjunct to dietary restriction of tyrosine and phenylalanine.

Documentation Required

Required Documentation for Initial Approval

Initial authorization requires documentation confirming the diagnosis of hereditary tyrosinemia type 1 (HT-1) and evidence that the medication will be used with dietary restriction.

Diagnosis confirmed by biochemical testing (e.g., detection of succinylacetone in urine), enzyme assay, or genetic testing.
Documentation that the requested medication is being used as an adjunct to dietary restriction of tyrosine and phenylalanine.

Background on Nitisinone and Indications

Nitisinone (marketed as Orfadin, Nityr, and generic nitisinone) is indicated for treatment of hereditary tyrosinemia type 1 (HT-1) in adults and pediatric patients when used in combination with dietary restriction of tyrosine and phenylalanine. Diagnostic confirmation for HT-1 may be biochemical (for example, detection of succinylacetone in urine), by enzyme assay, or by genetic testing. Therapy is managed alongside dietary measures and clinical monitoring of biochemical markers to assess response.

Definitions and Clinical Response

positive clinical response

DefinitionPositive clinical response: decrease in urinary/plasma succinylacetone and alpha-1-microglobulin levels while on therapy.

Use in continuation criteriaEvidence of positive clinical response is required for continuation of therapy (authorization of 6 months).

Examples of measurementsUrinary or plasma succinylacetone; alpha-1-microglobulin levels.

Member Eligibility Requirements

Coverage is limited to members with a confirmed diagnosis of hereditary tyrosinemia type 1 (HT-1). Diagnostic confirmation acceptable for authorization includes biochemical testing (e.g., detection of succinylacetone in urine), enzyme assay, or genetic testing. This policy applies to Medicaid members within the payer program scope and requires prior authorization; approvals are ordinarily granted for 6 months when initial criteria are met.

Not Covered Uses

Use of nitisinone for any indication other than treatment of hereditary tyrosinemia type 1 (HT-1) is considered experimental/investigational and is not covered.