CurrentCommunity-CarePolicy N/A

Laronidase (Aldurazyme) — Medical Benefit Coverage Criteria for Mucopolysaccharidosis I (MPS I)

Medical benefit coverage criteria for initiation and continuation of laronidase (Aldurazyme) in patients with Mucopolysaccharidosis I (MPS I); affects prescribers and payers administering this therapy under the medical benefit.

Policy Summary

PayerCommunity-Care

PolicyLaronidase (Aldurazyme) — Medical Benefit Coverage Criteria for Mucopolysaccharidosis I (MPS I)

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionObtain prior authorization with documentation confirming MPS I diagnosis (IDUA mutation or deficient α-L-iduronidase) and prescriber specialty.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 monthsminimum age for treatment

1 yearauthorization period

nonequantity limits

J1931HCPCS code

Coverage Criteria for Laronidase (Aldurazyme)

Initial Therapy Criteria

Covered when ALL of the following are met for initial approval:

Initial Approval: Prescribed by a medical geneticist or other provider specialized in the treatment of Mucopolysaccharidosis I

Patient is 6 months of age or older>= 6 months

Diagnostic confirmation: Diagnosis of Mucopolysaccharidosis I confirmed by ONE of the following:

ONE of

Documentation of genetic mutation in the IDUA gene

Policy Summary

PayerCommunity-Care

PolicyLaronidase (Aldurazyme) — Medical Benefit Coverage Criteria for Mucopolysaccharidosis I (MPS I)

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionObtain prior authorization with documentation confirming MPS I diagnosis (IDUA mutation or deficient α-L-iduronidase) and prescriber specialty.

SourceLink

On This Page

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Genetic testing of the IDUA gene is acceptable diagnostic confirmation

Documentation of deficient activity of α-L-iduronidase enzyme

Enzyme assay is acceptable diagnostic confirmation

Clinical form: Diagnosis is one of the following clinical forms: Hurler; Hurler-Scheie; or Scheie with moderate to severe symptoms

Continuation Therapy Criteria

Covered when ALL of the following are met for continuation of therapy:

Continuation Approval: Existing diagnosis of one of the specified MPS I forms: Hurler; Hurler-Scheie; or Scheie with moderate to severe symptoms

Response to therapy: Documentation of positive response to treatment with laronidase (Aldurazyme)

Positive response must be documented in the medical record

The policy does not list any separate or additional exclusions beyond the diagnostic, age, prescriber specialty, and clinical-form requirements specified for coverage. In other words, there are no explicit exclusions called out outside of the stated eligibility criteria (diagnostic confirmation, minimum age, required prescriber specialty, and specified MPS I clinical forms).

Use of laronidase (Aldurazyme) outside the stated criteria—such as in patients younger than 6 months, without documented confirmation of MPS I by either a pathogenic IDUA gene mutation or deficient α‑L‑iduronidase enzyme activity, without documentation of one of the specified clinical forms (Hurler, Hurler‑Scheie, or Scheie with moderate to severe symptoms), or when not prescribed by a medical geneticist or other provider specialized in MPS I—would be considered not medically necessary under this policy.

Diagnostic Evidence and Indications

Genetic Testing for IDUA (Diagnostic Confirmation)

Identification of a pathogenic IDUA mutation is acceptable diagnostic confirmation for coverage.

Genetic confirmation: Genetic testing demonstrating a pathogenic mutation in the IDUA gene consistent with Mucopolysaccharidosis I

Testing of the IDUA gene may be used instead of an enzyme assay to confirm diagnosis

Billing and Coding

Applicable HCPCS CodesHCPCSCovered

J1931

Injection, laronidase, 0.1 mg

inv-06: Minimum patient age

Minimum patient age>= 6 months

Authorization noteA weight is required for approval (used for dosing).

Authorization period if approved1 year

Provider Requirements and Prior Authorization

Prior Authorization

Prior Authorization Required

Prior authorization is required for laronidase (Aldurazyme) billed under HCPCS code J1931. Requests must include documentation meeting the initial approval criteria (confirmed MPS I diagnosis, prescriber specialty, age ≥ 6 months, and specified clinical form) and supporting clinical information.

HCPCS: J1931

Note

Documentation Required

Required Documentation

Required documentation includes confirmation of Mucopolysaccharidosis I (MPS I) by either: 1) documented pathogenic mutation(s) in the IDUA gene, or 2) documented deficient α-L-iduronidase enzyme activity. Also include the patient’s age, weight, clinical form of MPS I (Hurler, Hurler–Scheie, or Scheie with moderate–severe symptoms), prescriber specialty (medical geneticist or other MPS I specialist), and evidence of treatment response for continuation requests.

Denial Risk

Grounds for Denial

Denial may result if there is lack of documentation confirming MPS I (no IDUA mutation or enzyme deficiency), if the prescriber is not a specialist in MPS I, if the patient is under 6 months of age, or if the submitted materials do not support the required clinical form or treatment response criteria.

Note

Provider Actions

The ordering provider must be a medical geneticist or other provider specialized in the treatment of MPS I. Patient must be ≥ 6 months of age at time of request. For continuation of therapy include documentation of positive response to laronidase. A current weight is required for dosing and approval; approvals are issued for up to one year.

Key Definitions

inv-12: Confirmed MPS I

Definitive diagnostic evidence - geneticIdentification/documentation of a pathogenic mutation in the IDUA gene

Definitive diagnostic evidence - biochemicalLaboratory demonstration/documentation of deficient activity of α-L-iduronidase enzyme

Acceptable confirmation methodsEither IDUA gene mutation OR deficient α-L-iduronidase enzyme activity satisfies diagnostic confirmation

Eligibility Requirements

There are no top-level eligibility exceptions or prerequisites listed beyond the coverage criteria themselves. Eligibility for initial approval requires meeting all elements of the initial approval criteria (specialist prescriber, patient age ≥ 6 months, confirmed diagnosis by genetic testing or enzyme assay, and an eligible clinical form).

Background

Mucopolysaccharidosis I (MPS I) is a lysosomal storage disorder caused by deficiency of the α‑L‑iduronidase enzyme due to pathogenic variants in the IDUA gene. Enzyme deficiency leads to accumulation of glycosaminoglycans and the multisystem clinical manifestations seen in MPS I. Enzyme replacement with laronidase (Aldurazyme) is used to treat the non‑neurologic manifestations of MPS I and is managed by specialists experienced in this condition.

Not Covered / Limitations

The document does not identify any specific genetic tests or indications that are explicitly excluded from coverage. It states that no explicit genetic tests or indications are listed as not covered, so genetic testing of the IDUA gene for diagnostic confirmation is recognized as acceptable for coverage.