CurrentNeighborhood Health Plan of Rhode IslandPolicy N/A

Firdapse (amifampridine) for Lambert-Eaton myasthenic syndrome — Coverage Criteria

Covers authorization, continuation, exclusions, and quantity limits for Firdapse used to treat Lambert-Eaton myasthenic syndrome (LEMS) for members of Neighborhood Health Plan of Rhode Island when approval criteria are met.

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyFirdapse (amifampridine) for Lambert-Eaton myasthenic syndrome — Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionObtain prior authorization: initial approvals up to 6 months (reauthorization up to 12 months) and provide required documentation including diagnosis confirmation (EMG or antibody test) and prescriber specialty.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

6 moInitial authorization duration for LEMS

12 moContinuation authorization duration for responders

10/dayQuantity limit for Firdapse 10 mg

>=6Minimum age for covered indication

seizure hxExplicit exclusion

Policy Summary

PayerNeighborhood Health Plan of Rhode Island

PolicyFirdapse (amifampridine) for Lambert-Eaton myasthenic syndrome — Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

SourceLink

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Coverage Criteria for Firdapse (amifampridine)

Initial Therapy

Authorization of 6 months may be granted for treatment of LEMS in members 6 years and older when ALL of the following are met:

Initial Authorization Criteria: A. The prescriber is a neurologist.

Diagnosis Confirmation (one of):: B. Diagnosis is confirmed with documentation of one of the following:

1) EMG showing compound muscle action potential (CMAP) that increased at least 2-fold after maximum voluntary contraction of the tested muscle.>= 2-fold change

Cite EMG report documenting CMAP increase.

2) A positive anti–P/Q type voltage-gated calcium channel antibody test.

Provide laboratory report.

Additional Clinical Criteria: C. Documentation that the member has proximal muscle weakness.

Physical exam or clinical notes required.

Baseline Severity for Treatment-Naive Members: D. For treatment-naïve members, documentation of the Quantitative Myasthenia Gravis (QMG) score is at least 5.>= 5

Provide QMG score at baseline.

Continuation Therapy

Authorization of 12 months may be granted for continued treatment in members 6 years and older requesting reauthorization for LEMS when the following is met:

Continuation Criteria: Documentation of responding to therapy (i.e., stability or improvement in symptoms relative to the natural course of LEMS).

Authorization duration: up to 12 months. Provide clinical assessment comparing current status to pre-treatment baseline or prior visit notes.

Coverage is explicitly excluded for members with a documented history of seizures. Requests for Firdapse (amifampridine) will be denied when medical records indicate a prior seizure disorder or seizure event, per policy exclusion.

Firdapse is covered only for its FDA‑approved indication(s) and compendial uses. All other indications beyond FDA‑approved and compendial uses are considered experimental/investigational and not medically necessary. Requests for coverage for non‑approved indications should be denied as not medically necessary.

Coding and Clinical Measures

Quantitative Myasthenia Gravis (QMG) score

QMG score thresholdQuantitative Myasthenia Gravis (QMG) score is at least 5 for treatment‑naïve members

Context of useRequired only for treatment‑naïve members as part of initial authorization for LEMS

Authorization linkageMeets this threshold supports initial authorization of up to 6 months

Provider Actions and Authorization Requirements

Prior Authorization

Prior authorization durations

Prior authorization is required. Initial authorizations for treatment of LEMS may be granted for up to 6 months; reauthorization for members who are responding may be granted for up to 12 months.

Step Therapy

Step therapy

No step therapy requirements are specified in this policy.

Documentation Required

Required documentation for initial authorization

For initial authorization, provide documentation confirming the diagnosis: EMG showing CMAP that increased at least 2-fold after maximum voluntary contraction OR a positive anti‑P/Q type voltage-gated calcium channel antibody test; documentation of proximal muscle weakness; for treatment‑naïve members, QMG score of at least 5; and the prescriber must be a neurologist.

Background

Firdapse (amifampridine) is indicated for the treatment of Lambert‑Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years and older. Coverage under this policy is limited to that FDA‑approved indication and compendial uses; other uses are considered experimental/investigational and not medically necessary.

Definitions and Diagnostic Criteria

LEMS indication

Indication statementFirdapse is indicated for treatment of Lambert‑Eaton myasthenic syndrome (LEMS) in adults and pediatric patients 6 years and older

Minimum ageApplies to members aged 6 years and older

ScopeCoverage limited to FDA‑approved indication; other uses considered experimental/investigational and not medically necessary

Diagnosis confirmation

EMG diagnostic criterionEMG showing compound muscle action potential (CMAP) that increased at least 2‑fold after maximum voluntary contraction of the tested muscle

Serologic diagnostic criterionA positive anti‑P/Q type voltage‑gated calcium channel (VGCC) antibody test