Aldurazyme (laronidase)

Coverage Summary

Aldurazyme (laronidase) — covered_with_criteria. Defines medical necessity criteria, continuation criteria, exclusions, quantity limit and applicable billing codes for Aldurazyme (laronidase) when reviewed under the medical benefit/prior authorization process. Includes requirements for diagnostic confirmation, documentation for continuation (improvement or stabilization), exclusion for Scheie syndrome with mild symptoms, a quantity limit of 0.58 mg/kg once weekly for the 2.9 mg vial, and primary billing using J1931. Aldurazyme carries a black box warning for hypersensitivity; life‑threatening anaphylaxis has occurred during infusions and appropriate medical support should be available during administration.

Initial therapy - Approval criteria

Initial requests for Aldurazyme (laronidase) may be approved if the following criteria are met:

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Continuation Therapy Criteria

Continuation therapy - Approval criteria

Continuation requests for Aldurazyme (laronidase) may be approved when documentation shows clinically significant improvement or stabilization in disease-related signs and symptoms compared to the expected natural history.

ALL of the following

Documentation is provided that there is clinically significant improvement or stabilization in clinical signs and symptoms of disease compared to the predicted natural history trajectory of disease.
Examples of clinically significant improvement or stabilization include, but are not limited to: reduction in urinary GAG excretion; reduction in hepatosplenomegaly; improvement in pulmonary function; improvement in walking distance (e.g., 6-minute walk test) and/or improvement in fine or gross motor function.

Prior Authorization

Continuation authorization requirement

Prior authorization required for continuation. Provide documentation of clinical response or stabilization compared to expected natural history. Include documentation of dosing and quantity administered to justify continued therapy.

Prior authorization required for continuation requests
HCPCS: J1931 — Injection, laronidase, 0.1 mg
Quantity limit/billing: Aldurazyme 2.9 mg vial — limit = 0.58 mg/kg once a week (ensure billed units align with J1931 units: J1931 = 0.1 mg per unit)

Exclusions / Not Approved

Exclusions / Not approved

Requests may not be approved when any of the following apply:

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Denial Risk

Denial risk for Scheie with mild symptoms

Do not request Aldurazyme for individuals with Scheie syndrome who have only mild symptoms; such requests are excluded and may be denied if the exclusion applies.

Applicable Codes

HCPCS - drug administrationHCPCSCovered

J1931	Injection, laronidase, 0.1 mg (Aldurazyme)
S9357	Home infusion therapy, enzyme replacement intravenous therapy, (e.g., Imiglucerase); administrative services, professional pharmacy services, care coordination, and all necessary supplies and equipment (drugs and nursing visits coded separately), per diem

ICD-10 Diagnosis codes referencedICD-10

E76.01	Hurler's syndrome
E76.02	Hurler-Scheie syndrome
E76.03	Scheie's syndrome

Billing Rule

Quantity limit / Billing instructions

Adhere to the product-specific quantity limit and bill using the laronidase HCPCS code. Bill laronidase using J1931 (0.1 mg per unit). The quantity limit is 0.58 mg/kg once weekly; vial size is 2.9 mg.

Bill laronidase using J1931 (Injection, laronidase, 0.1 mg)
Quantity limit: 0.58 mg/kg once weekly
Vial size: 2.9 mg

Provider Actions & Documentation

Prior Authorization

Prior authorization required with diagnostic confirmation

Prior authorization is required. Submit documentation of diagnosis (Hurler, Hurler-Scheie, or Scheie with moderate–severe symptoms) AND confirmatory testing showing either alpha-L-iduronidase enzyme deficiency in fibroblasts or leukocytes OR a pathogenic alpha-L-iduronidase gene mutation to support medical necessity.

Diagnosis codes: Hurler (E76.01), Hurler-Scheie (E76.02), Scheie with moderate–severe symptoms (E76.03)
Confirmatory testing: enzyme assay in fibroblasts or leukocytes OR alpha-L-iduronidase gene mutation
Affecting HCPCS: J1931

Documentation Required

Safety monitoring and documentation

Document monitoring and precautions for hypersensitivity and anaphylaxis risk per the product labeling. Ensure appropriate medical support is available during infusions and document respiratory monitoring for individuals with compromised respiratory function or acute respiratory disease.

Clinical Evidence & References

References cited: Clarke 2021; Thomas 2010; Wang 2011; Lehman 2011; and product labeling (DailyMed). The FDA approval covers treatment of Mucopolysaccharidosis I (MPS I) syndromes (Hurler, Hurler‑Scheie, and Scheie) with the explicit limitation that Aldurazyme is not approved for individuals with Scheie syndrome who exhibit only mild symptoms.

Background

Aldurazyme (laronidase) is an FDA‑approved enzyme replacement therapy for Mucopolysaccharidosis I (MPS I). MPS I is caused by deficiency of the lysosomal enzyme alpha‑L‑iduronidase, leading to progressive accumulation of glycosaminoglycans (GAGs) in lysosomes and resulting in multi‑system complications affecting respiratory, cardiac, skeletal, neurologic and ophthalmologic systems. Aldurazyme replaces deficient alpha‑L‑iduronidase activity to address disease manifestations. The product carries a black box warning for hypersensitivity reactions; life‑threatening anaphylaxis has occurred during infusions, so appropriate medical support must be available during administration and patients with compromised or acute respiratory disease require additional monitoring.

Policy metadata quick facts

Policy numberCC-0025

SubjectAldurazyme (laronidase)

StatusCURRENT

Last review date2025-09-08

Scope summary

Revision History

2025-09-08reviewLatest

Select Review: No changes. Coding reviewed — removed ICD-10-CM E76.3. (non-material coding change)

2024-09-09review

Annual Review: No changes. Coding reviewed: No changes.

2023-09-11review

Annual Review: Wording and formatting changes; updated references. Coding reviewed: No changes.