CurrentmhnPolicy CP.PHAR.374

Vestronidase Alfa-vjbk (Mepsevii)

Medical necessity and prior authorization criteria for coverage of Mepsevii (vestronidase alfa-vjbk) for treatment of Mucopolysaccharidosis VII (MPS VII, Sly syndrome) for commercial, HIM and Medicaid lines of business.

Policy Summary

Payermhn

PolicyVestronidase Alfa-vjbk (Mepsevii)

Policy CodePolicy CP.PHAR.374

Change TypeNo material changes

Effective DateSep 1, 2018

Next Review Date

Key ActionSubmit prior authorization with clinical documentation including diagnosis confirmation and the member's current weight.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

4 mg/kgMax dose

6 monthsApproval duration

J3397HCPCS

Boxed anaphylaxisSafety

Current weightReq docs

2018Effective year

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Coverage Criteria

inv-21: Diagnostic confirmation of MPS VII via DNA testing showing GUSB gene mutation

Diagnostic confirmation acceptable for coverage:

Diagnostic confirmation of MPS VII: One DNA test showing a GUSB gene mutation is acceptable to confirm diagnosis for coverage purposes.

Alternatively, diagnosis may be confirmed by two repeated enzyme assay tests demonstrating beta-glucuronidase deficiency.

Non-FDA approved indications not addressed in this policy are not authorized unless there is sufficient documentation of efficacy and safety according to the applicable off-label use policies (e.g., CP.CPA.09, HIM.PA.154, CP.PMN.53) or the member's evidence of coverage documents.

Coverage decisions and the administration of benefits are subject to all terms, conditions, exclusions, and limitations of the member's coverage documents (for example, evidence of coverage, certificate of coverage, policy, contract of insurance) as well as state and federal requirements and applicable Health Plan-level administrative policies and procedures.

Uses for indications that are not FDA-approved and are not supported by the off-label use policies or the member's evidence of coverage are considered not authorized and may be denied.

Coding

HCPCS CodesHCPCS

J3397

Injection, vestronidase alfa-vjbk, 1 mg

Maximum dose

Maximum dose4 mg/kg IV every 2 weeks

Dosing frequencyEvery 2 weeks (IV)

Route of administrationIntravenous (IV)

Provider Actions & Prior Authorization

Prior Authorization

Prior Authorization Required

Prior authorization is required. Providers must submit clinical documentation (such as office chart notes, lab results, genetic or enzyme testing results, current weight in kg, and specialty consultation notes) demonstrating the member meets all approval criteria for MPS VII (Sly syndrome). Approvals are issued for 6 months for Medicaid/HIM and for 6 months or to the member's renewal date (whichever is longer) for Commercial lines of business.

Prior authorization required for initiation and continuation of Mepsevii for MPS VII (Sly syndrome).
Approval durations: Medicaid/HIM — 6 months; Commercial — 6 months or to member renewal date, whichever is longer.

Denial Risk

Non‑FDA Use May Trigger Denial

Requests for indications that are not FDA‑approved and are not addressed in this policy may be denied unless sufficient documentation of efficacy and safety is provided in accordance with applicable off‑label use policies and the member's coverage documents. Refer to off‑label policies CP.CPA.09 (Commercial), HIM.PA.154 (Health Insurance Marketplace), and CP.PMN.53 (Medicaid) as applicable.

Definitions

Vestronidase alfa (Mepsevii)

Generic and brand nameVestronidase alfa (Mepsevii)

Drug classRecombinant human lysosomal beta-glucuronidase enzyme replacement therapy

FDA indicationTreatment of Mucopolysaccharidosis VII (MPS VII, Sly syndrome) in pediatric and adult patients

Limitation of useEffect on central nervous system manifestations of MPS VII has not been determined

Confirmed MPS VII diagnosis

Diagnostic confirmation optionsTwo repeated enzyme assay tests demonstrating beta-glucuronidase deficiency OR one DNA test showing GUSB gene mutation

Enzyme assay requirement

Eligibility Requirements

There are no top-level eligibility requirement nodes specified for this policy.

Background

Mucopolysaccharidosis VII (Sly syndrome) is a lysosomal storage disease caused by deficiency of beta-glucuronidase. Vestronidase alfa (Mepsevii) is a recombinant human lysosomal beta-glucuronidase enzyme replacement therapy indicated for pediatric and adult patients with MPS VII; its effect on central nervous system manifestations is undetermined. Diagnosis for coverage may be confirmed by either two repeated enzyme assays demonstrating beta-glucuronidase deficiency or one DNA test showing a GUSB gene mutation. Treatment must be prescribed by or in consultation with a specialist with expertise in lysosomal storage diseases, and documentation of the member's current weight (kg) is required for initial and continued approval. The dosing regimen should not exceed 4 mg/kg IV every 2 weeks.

Policy Summary

Payermhn

PolicyVestronidase Alfa-vjbk (Mepsevii)

Policy CodePolicy CP.PHAR.374

Change TypeNo material changes

Effective DateSep 1, 2018

Next Review Date

Key ActionSubmit prior authorization with clinical documentation including diagnosis confirmation and the member's current weight.

SourceLink

On This Page

Non‑FDA uses require documentation per applicable off‑label policies (CP.CPA.09, HIM.PA.154, CP.PMN.53).
Coverage denied when off‑label requests lack sufficient supporting evidence per the Health Plan's off‑label and coverage policies.

Documentation Required

Required Clinical Documentation & Administrative Adherence

Providers must follow Health Plan‑level administrative policies and the member's coverage documents when requesting coverage. Treatment must be prescribed by or in consultation with a specialist with expertise in lysosomal storage diseases. All requests should include supporting documentation that the member meets clinical criteria (diagnostic confirmation by enzyme assay or genetic testing, clinical signs of disease, current weight, dosing not to exceed 4 mg/kg IV every 2 weeks) and any additional documents requested by the Health Plan.

Provider must submit office/chart notes, lab results, genetic or enzyme testing, weight, and specialist consultation notes.
Treatment must be prescribed by or in consultation with a lysosomal storage disease specialist.

Two repeated beta-glucuronidase enzyme assays demonstrating deficiency

Genetic test requirementDNA testing showing a GUSB gene mutation (single test acceptable)

Clinical policy

Purpose of clinical policyProvides guidance to assist in making coverage decisions and administering benefits

Not a contractDoes not constitute a contract or guarantee regarding payment or results

Basis for developmentDeveloped by experienced health care professionals using accepted standards, literature, and regulatory status

Provider role

Provider statusProviders referenced are independent contractors who exercise independent medical judgment

Policy does not dictate carePolicy is not intended to dictate how providers practice medicine

Provider responsibilityProviders are solely responsible for medical advice and treatment of members