CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Coverage Criteria: Miplyffa (arimoclomol) and Aqneursa (levacetylleucine) for Niemann‑Pick Disease Type C

This policy governs authorization, continuation, and quantity limits for Miplyffa and Aqneursa for treatment of neurological manifestations of Niemann‑Pick disease type C (NPC) for eligible members, and applies to clinicians prescribing these therapies.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyCoverage Criteria for Miplyffa and Aqneursa for NPC

Policy CodePolicy N/A

Change TypeNo material changes

Effective DateN/A

Next Review DateN/A

Key ActionObtain prior authorization with documented baseline 5‑domain NPCCSS, diagnostic confirmation, prescriber specialty, and required concomitant therapy/dose information.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 monthsAuthorization duration

3/dayMiplyffa qty limit

4/dayAqneursa qty limit

5-domain NPCCSSAssessment tool

VariesAge-based criteria

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Coverage Criteria

Initial Therapy

Covered when ALL of the following are met for initial authorization (6 months):

Initial authorization for NPC therapy

Baseline assessment: Documentation of 5-domain NPC Clinical Severity Scale (NPCCSS) assessment to establish baseline score.
Diagnostic confirmation: Diagnosis confirmed by either (a) genetically confirmed variant in both alleles of NPC1 or NPC2 OR (b) mutation in one allele of NPC1 or NPC2 plus positive filipin staining or elevated cholestane-triol (>2× upper limit of normal).>2 times the upper limit of normal
Clinical manifestations: Medical records documenting neurological manifestations of NPC (e.g., loss of fine motor skills, swallowing, speech, ambulation).
Concomitant miglustat status (relevant for Miplyffa): Stable on miglustat (e.g., Opfolda) for 6 months, except when miglustat is not recommended (advanced neurological disease and/or dementia, early‑infantile NPC, or visceral-only disease).
Functional ambulation: Member has the ability to walk either independently or with assistance.
Prescriber specialty: Medication prescribed by or in consultation with an endocrinologist, geneticist, neurologist, or physician who specializes in metabolic disease/lysosomal storage disorders.

If request is for Aqneursa (levacetylleucine): Member is 4 to 64 years of age; documentation that member weighs ≥15 kg and prescribed dose is in accordance with FDA‑approved labeling based on current weight; requested medication will not be used in combination with Miplyffa for NPC treatment.

If request is for Miplyffa (arimoclomol): Member is 2 to 19 years of age; member does NOT have adult‑onset NPC (first neurological symptom >15 years); documentation of current weight and prescribed dose per FDA‑approved labeling; medication will be used in combination with miglustat and will not be used in combination with Aqneursa for NPC treatment.

Product-specific Initial Criteria

Product-specific initial criteria (additional requirements):

Aqneursa-specific: Member age 4 to 64 years; documented weight ≥15 kg with prescribed dose in accordance with FDA‑approved labeling based on current weight; therapy will not be used in combination with Miplyffa (arimoclomol) for treatment of NPC.

Miplyffa-specific: Member age 2 to 19 years; member does NOT have adult‑onset NPC (adult‑onset defined as first neurological symptom >15 years); documentation of current weight and dosing per FDA‑approved labeling; therapy will be used in combination with miglustat (unless miglustat is not recommended) and will not be used in combination with Aqneursa for treatment of NPC.

Continuation Therapy

Covered for continuation when ALL of the following are met for reauthorization (6 months):

Continuation Therapy: Member meets the criteria for initial approval AND there is documentation that the member is experiencing benefit from therapy (e.g., stabilization or improvement in 5‑domain NPCCSS score, fine motor skills, swallowing, speech, or ambulation).

All indications for use beyond the FDA-approved indications and compendial uses listed in this policy are considered experimental/investigational and are not covered.

Use of Miplyffa, Aqneursa, or related therapies for indications other than the specified FDA-approved indications (or recognized compendial uses) is not medically necessary and will not be approved.

Coding and Quantity Limits

Cholestane‑triol level

Diagnostic threshold>2 times the upper limit of normal

Context of useSupports diagnostic confirmation when a single NPC1 or NPC2 allele mutation is present plus elevated cholestane-triol (alternative to biallelic genetic confirmation)

Documentation requirementMust be documented in medical record or laboratory report to meet coverage criteria

Miplyffa quantity limit

Quantity limit3 capsules per day

Applies toMiplyffa 47 mg, 62 mg, 93 mg, 124 mg capsules

Provider Actions and Requirements

Prior Authorization

Prior Authorization Required

Prior authorization required. Initial authorization may be granted for up to 6 months when all diagnostic, baseline assessment, prescriber specialty, age, dosing, and combination-therapy criteria are met. Reauthorization (continuation of therapy) may be granted for up to 6 months when the member meets initial approval criteria and documentation shows clinical benefit (e.g., stabilization or improvement in 5-domain NPCCSS score or improvement in fine motor skills, swallowing, speech, or ambulation).

Initial and reauthorization approvals may be granted for 6 months.
Reauthorization requires documentation of clinical benefit (stabilization or improvement on 5-domain NPCCSS or functional measures).

Denial Risk

Insufficient Diagnostic Documentation May Lead to Denial

Requests lacking required diagnostic confirmation or documentation of neurological manifestations may be denied. Ensure genetic confirmation and clinical records are included with the request; missing baseline NPCCSS or absence of documented neurological signs increases denial risk.

Background

Niemann‑Pick disease type C (NPC) is a rare lysosomal storage disorder characterized by progressive neurological manifestations. Clinical features commonly include deficits in ambulation, fine motor skills, swallowing, speech, and cognition. These neurological manifestations are the target of the FDA‑approved therapies addressed by this policy, and severity/response is measured using the 5‑domain Niemann‑Pick Clinical Severity Scale (NPCCSS).

Definitions

Adult‑onset NPC definition

DefinitionAdult-onset NPC is defined as first neurological symptom occurring > 15 years of age.

Relevance to MiplyffaMembers with adult-onset NPC are excluded from Miplyffa eligibility (Miplyffa reserved for age 2–19 years with first symptom ≤15 years)

DocumentationAge of first neurological symptom must be documented in the medical record to determine adult-onset status