CurrentCareSourcePolicy N/A

Aldurazyme (laronidase) prior authorization for Mucopolysaccharidosis I (MPS I)

Defines medical necessity and prior authorization requirements for coverage of Aldurazyme (laronidase) for members with MPS I under the Arkansas PASSE medical benefit; applies to providers requesting coverage for this therapy.

Policy Summary

PayerCareSource

PolicyAldurazyme (laronidase) prior authorization for Mucopolysaccharidosis I (MPS I)

Policy CodePolicy N/A

Change TypeRemoved age limitadded severity terms

Effective DateJul 1, 2024

Next Review DateN/A

Key ActionObtain prior authorization; initial approvals granted for 6 months when diagnostic and prescribing criteria are met.

SourceLink

POLICY UPDATE CHANGES

Removed age limit.

Added the terms severe and attenuated.

0.58 mg/kgauthorized IV dose per infusion

6 moinitial approval duration

12 moreauthorization approval duration

prior authcoverage status

Coverage and Medical Necessity Criteria

Policy Summary

PayerCareSource

PolicyAldurazyme (laronidase) prior authorization for Mucopolysaccharidosis I (MPS I)

Policy CodePolicy N/A

Change TypeRemoved age limitadded severity terms

Effective DateJul 1, 2024

Next Review DateN/A

Key ActionObtain prior authorization; initial approvals granted for 6 months when diagnostic and prescribing criteria are met.

SourceLink

On This Page

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Prescriber: Medication must be prescribed by or in consultation with a geneticist, metabolic specialist, or pediatrician experienced with managing mucopolysaccharidoses

Diagnosis: Member has a documented diagnosis of ONE of the following forms of MPS I: Hurler syndrome (severe), Hurler-Scheie syndrome (attenuated), OR Scheie syndrome with moderate to severe symptoms

Diagnostic Confirmation: Member's MPS diagnosis confirmed by at least one of: low IDUA enzyme activity (<10%) and/or molecular genetic testing identifying pathogenic IDUA mutationsIDUA <10%

Dose and Duration: Dosage allowed: 0.58 mg/kg IV infusion once weekly; if criteria met, initial approval for 6 months0.58 mg/kg weekly; approval 6 months

inv-02: Continuation Therapy / Reauthorization — Covered for continuation when ALL of the following are met

Covered for continuation when ALL of the following are met

Clinical Response: Chart notes must show improvement or stabilized signs and symptoms of disease such as improved functional capacity (e.g., 6-minute walk test, forced vital capacity), reduced hepatomegaly, and/or reduced uGAG levels compared to baseline

If met, approve for additional 12 months

Initial Therapy Requirements

inv-14: Initial Therapy — Initial approval when diagnostic and prescriber criteria are met

Initial approval when diagnostic and prescriber criteria are met

Prescriber: Prescribed by or in consultation with a geneticist, metabolic specialist, or experienced pediatrician

Diagnostic confirmation: Low IDUA enzyme activity (<10%) and/or molecular genetic testing identifying pathogenic IDUA mutationsIDUA <10%

Dose: 0.58 mg/kg IV infusion once weekly; initial approval for 6 months0.58 mg/kg weekly

Reauthorization / Continuation Requirements

inv-15: Reauthorization — Reauthorization requirements for continuation of Aldurazyme

Reauthorization requirements for continuation of Aldurazyme

Clinical benefit: Documentation of improvement or stabilization in disease signs/symptoms (e.g., 6-minute walk test, FVC), reduced hepatomegaly, and/or reduced uGAG levels

Approval for 12 months if met

Coding, Dosage and Laboratory Thresholds

Dosage/Quantitymixed

0.58 mg/kg

Dosage allowed per IV infusion (documented as quantity limit)

inv-06: Low IDUA enzyme activity — < 10%

ThresholdLow IDUA enzyme activity < 10%

ContextDefined as part of diagnostic confirmation for MPS I in this policy

UseAcceptable as one method to confirm MPS I when combined with clinical diagnosis

inv-13: Low IDUA activity — Low IDUA enzyme activity defined in this policy as less than 10%

DefinitionLow IDUA enzyme activity is defined in this policy as less than 10%

Role in criteriaServes as one option for diagnostic confirmation of MPS I (may be used alone or with genetic testing)

ApplicationRequired for initial authorization when documenting MPS I diagnosis per policy

Provider Requirements and Documentation

Prior Authorization

Prior Authorization Required

Prior authorization is required for Aldurazyme (laronidase) under the medical benefit. Initial approvals are granted for 6 months; reauthorization approvals are granted for 12 months when continuation criteria are met.

Benefit type: Medical
Initial approval: 6 months
Reauthorization: 12 months (if criteria met)

Step Therapy

No step therapy requirements are specified in this policy.

Documentation Required

Required Clinical Documentation

Prescriber documentation must include confirmation of diagnosis and supporting clinical information. For initial authorization, documentation must show: diagnosis of MPS I (Hurler, Hurler–Scheie, or Scheie with moderate–severe symptoms); low IDUA enzyme activity (<10%) and/or molecular genetic testing identifying pathogenic IDUA mutations; and that the medication is prescribed by or in consultation with a geneticist, metabolic specialist, or pediatrician experienced in MPS. Include proposed dose (0.58 mg/kg IV once weekly). For reauthorization, chart notes must document improvement or stabilization of signs/symptoms (for example, improved 6-minute walk test, increased FVC, reduced hepatomegaly, and/or reduced urinary GAG levels).

Prescriber: geneticist, metabolic specialist, or pediatrician experienced with mucopolysaccharidoses
Initial documentation: diagnosis subtype, <10% IDUA activity and/or pathogenic IDUA mutation
Dose specified: 0.58 mg/kg IV weekly
Reauthorization documentation: clinical improvement or stabilization (e.g., 6MWT, FVC, hepatomegaly, uGAG)

Denial Risk

Off‑label/Other Indications

Use of Aldurazyme for indications not listed in this policy is considered not medically necessary and may be denied. Refer to the payer's Off‑Label policy for other indications.

Definitions and Background

Mucopolysaccharidosis type I (MPS I) is a rare lysosomal storage disorder caused by pathogenic mutations in the IDUA gene resulting in deficient or absent alpha‑L‑iduronidase activity and accumulation of glycosaminoglycans (heparan sulfate and dermatan sulfate) with multisystem manifestations. Aldurazyme (laronidase) is an enzyme replacement therapy (ERT) that provides exogenous IDUA to reduce substrate accumulation; it does not address central nervous system manifestations, and the benefit in mildly affected Scheie patients is not well established.

inv-12: ERT — Enzyme replacement therapy (ERT)

TermEnzyme replacement therapy (ERT)

DescriptionAldurazyme is an ERT that provides exogenous alpha-L-iduronidase to replace deficient endogenous enzyme

IndicationUsed to treat Mucopolysaccharidosis type I (MPS I) per policy and FDA approval

OpenPayer