CurrentMass General Brigham Health PlanPolicy N/A

Vimizim (elosulfase alfa) coverage

Defines prior authorization, quantity/step therapy and continuation criteria for Vimizim (elosulfase alfa) under Mass General Brigham Health Plan pharmacy and specialty benefits; applies to members receiving the drug for MPS IVA.

Policy Summary

PayerMass General Brigham Health Plan

PolicyVimizim (elosulfase alfa) coverage

Policy CodePolicy N/A

Change TypeOperational revision

Effective DateJan 1, 2024

Next Review DateN/A

Key ActionSubmit prior authorization with diagnostic documentation (enzyme assay or genetic testing) and evidence of clinical response for continuation.

SourceLink

POLICY UPDATE CHANGES

Policy was switched from SGM to Custom effective 1/1/2024 following Dec P&T review.

FDA-approvedCovered indication(s)

PA requiredAccess control

Clinical responseRenewal criteria

Enzyme/geneticDiagnostic verification

Coverage Criteria — Vimizim (elosulfase alfa)

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Initial Therapy

Covered when ALL of the following are met:

Initial authorization criteria: 1) Member has a diagnosis of MPS IVA (Morquio A syndrome); 2) Submission of medical records demonstrating an enzyme assay showing deficiency of N-acetylgalactosamine-6-sulfatase OR genetic testing confirming the diagnosis; 3) Prior authorization submitted — may be granted for members new to the plan who are currently receiving treatment (excluding product obtained as samples or via manufacturer patient assistance programs).

Continuation Therapy

Covered when ALL of the following are met:

Continuation criteria: Documentation of clinically positive response to therapy, defined as improvement, stabilization, or slowing of disease progression; ongoing authorization contingent on submitted documentation. For members new to the plan who are currently receiving treatment, provide records showing ongoing treatment as part of the request.

Coverage of Vimizim (elosulfase alfa) under this policy is limited to the FDA-approved indication: Mucopolysaccharidosis type IVA (MPS IVA, Morquio A syndrome). Any use outside this FDA-approved indication is considered experimental/investigational and not medically necessary.

Use of Vimizim for indications other than MPS IVA (Morquio A syndrome) is explicitly considered not medically necessary and may be denied.

Initial Therapy Requirements

Initial Therapy

Covered when ALL of the following are met:

Initial therapy: Member has MPS IVA (Morquio A syndrome); submission of medical records demonstrating enzyme assay showing deficiency of N-acetylgalactosamine-6-sulfatase OR genetic testing confirming diagnosis; prior authorization submitted — may be granted for members new to the plan who are currently receiving treatment (excluding samples or manufacturer's patient assistance program supplies).

Continuation / Renewal Criteria

Continuation Therapy

Covered when ALL of the following are met:

Continuation: Documentation of clinically positive response (improvement, stabilization, or slowing of disease progression) is required for ongoing authorization; include documentation of ongoing treatment for members new to the plan.

Provide clinical records demonstrating response as part of continuation request.

Provider Actions and Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for Vimizim (elosulfase alfa). For members new to the plan, authorization may be granted when the member is currently receiving the requested medication (excluding samples or manufacturer patient assistance program supply). Contact the plan for prior authorization submission details.

All Plans Prior Authorization Phone: 877-519-1908, Fax: 855-540-3693
Non-Specialty Medications Phone: 800-711-4555, Fax: 844-403-1029

Step Therapy

Step and Quantity Controls May Apply

Step therapy or quantity limits may apply according to the member's benefit design. Check the member's benefit plan for applicable step-therapy requirements and any specialty/quantity limits prior to prescribing.

Program Type: Quantity Limit, Step Therapy
Benefits: Pharmacy Benefit, Medical Benefit

Documentation Required

Diagnostic Documentation Required

Diagnostic documentation is required with the authorization request. Submit objective confirmation of MPS IVA, such as enzyme assay results demonstrating deficiency of N-acetylgalactosamine-6-sulfatase activity or genetic testing confirming the diagnosis.

Required: Enzyme assay demonstrating deficiency OR genetic testing confirming MPS IVA
Diagnosis must support FDA-approved indication: Mucopolysaccharidosis type IVA (MPS IVA, Morquio A syndrome)

Documentation Required

Continuation Documentation Required

For renewal/continuation requests, provide documentation of clinically positive response to therapy, defined as improvement, stabilization, or slowing of disease progression.

Documentation should include clinical notes, objective measures, or other evidence of benefit
Continuation authorization may be granted when clinically positive response is demonstrated

Denial Risk

Indication-Based Denial Risk

Requests for indications other than the FDA-approved indication for MPS IVA (Morquio A syndrome) will be considered experimental/investigational and not medically necessary.

FDA-Approved Indication: Mucopolysaccharidosis type IVA (MPS IVA, Morquio A syndrome)
All other indications: Experimental/Investigational — Not medically necessary

Authorization and Billing Codes

Authorization / billing codesmixed

affected codes

Policy references prior authorization and benefit codes; specific HCPCS/CPT/NDC codes not listed in document.

Clinical response — continuation criteria

Acceptable clinical responsesImprovement in clinical signs or symptoms of MPS IVA

StabilizationStabilization of disease without further clinical decline

Slowing of progressionSlowing of disease progression compared to prior trajectory

Step Therapy and Quantity Controls

Step	Description	Prior Authorization
1	Step therapy may apply per the plan benefit design; quantity limits and specialty medication handling may also apply.	Prior authorization required as part of step/quantity controls.

Quantity Limits

Vimizim (elosulfase alfa) — quantity limits

Quantity limit applicabilityQuantity limits applicable per plan benefit design (Pharmacy Benefit / Quantity Limit)

Program typesApplies to Commercial/Exchange; may be subject to MassHealth UPPL plan rules

Benefit handlingManaged under Pharmacy Benefit with specialty medication handling and step therapy as applicable

Site of Care and Administration

Note

Follow plan for site‑of‑care and infusion handling

Site‑of‑care is not specified in this policy; follow the member's plan benefit design and specialty medication handling (e.g., infusion center policies) for administration location.

Background

Mucopolysaccharidosis type IVA (MPS IVA, Morquio A syndrome) is the FDA-approved indication for Vimizim (elosulfase alfa). The condition is caused by deficiency of the enzyme targeted by this enzyme replacement therapy; Vimizim is indicated to treat patients with confirmed MPS IVA. Diagnostic confirmation (for authorization) requires laboratory or genetic evidence consistent with MPS IVA.

Definitions

MPS IVA definition — confirmatory testing

Confirmatory testing — enzyme assaySubmission of medical records of an enzyme assay demonstrating deficiency of N-acetylgalactosamine-6-sulfatase enzyme activity

Confirmatory testing — genetic testingGenetic testing confirming diagnosis of MPS IVA (Morquio A syndrome)

Acceptable documentationMedical records demonstrating either enzyme assay results or genetic testing must be submitted with authorization request

Revision History

2024-01-01operational changeLatest

Policy implementation type changed from SGM to Custom following the December P&T review; change effective January 1, 2024.

2023-12-13review

Policy reviewed at December P&T where decision was made to switch the policy from SGM to Custom, effective 1/1/2024.

Policy Summary

PayerMass General Brigham Health Plan

PolicyVimizim (elosulfase alfa) coverage

Policy CodePolicy N/A

Change TypeOperational revision

Effective DateJan 1, 2024

Next Review DateN/A

Key ActionSubmit prior authorization with diagnostic documentation (enzyme assay or genetic testing) and evidence of clinical response for continuation.

SourceLink

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