CurrentAetnaPolicy N/A

Amondys 45 (casimersen) Injectable Medication Precertification Request - Coverage Criteria

Precertification form and requirements for initiating or continuing Amondys 45 (casimersen) for members covered by Aetna; used by prescribers, infusion sites, and dispensing providers to request authorization.

Policy Summary

PayerAetna

PolicyAmondys 45 (casimersen) Precertification / Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionSubmit a completed precertification form with demographics, weight/height, prescriber and dispensing provider information, product dose/frequency, genetic testing confirming DMD and mutation amenable to exon 45 skipping, 6-minute walk test result, and prior gene therapy history.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

300 m6-minute walk test minimum

≤30 mg/kgDose limit

NeurologistPreferred prescriber

Part BMedicare note

Coverage Criteria for Amondys 45 (casimersen)

Policy Summary

PayerAetna

PolicyAmondys 45 (casimersen) Precertification / Coverage Criteria

Policy CodePolicy N/A

Change TypeNo material changes

Effective Date

Next Review Date

SourceLink

On This Page

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Initial request requirements: 1) Genetic testing confirming diagnosis of Duchenne muscular dystrophy (DMD); 2) Genetic testing identifying the specific DMD gene mutation that is amenable to exon 45 skipping; 3) Patient is able to achieve an average distance of at least 300 meters on the 6-minute walk test while walking independently; 4) Treatment will be initiated prior to age 14; 5) Documentation of prior gene replacement therapy status (has not received gene replacement therapy, or if received, documentation regarding clinical course including whether there has been clinical worsening)

As listed on the initial requests section of the precertification form

Re-starting Therapy After Gene Replacement

Re-starting therapy after gene replacement is allowed when ALL of the following are met

Re-start requirements after gene replacement: 1) Genetic testing confirming diagnosis of Duchenne muscular dystrophy (DMD); 2) Genetic testing identifying the specific DMD gene mutation that is amenable to exon 45 skipping; 3) Patient is able to achieve an average distance of at least 300 meters on the 6-minute walk test while walking independently; 4) Treatment is being initiated prior to age 14; 5) Documentation that the patient has experienced clinical worsening since receiving gene replacement therapy (e.g., decline in ambulatory function) when applicable

Per re-starting therapy section of the precertification form

Coverage is not provided when genetic testing does not confirm Duchenne muscular dystrophy (DMD) or when testing documents a DMD gene mutation that is not amenable to exon 45 skipping. The precertification form requires documentation that genetic testing both confirms the diagnosis of DMD and identifies the specific mutation, and it specifically asks whether the mutation is amenable to exon 45 skipping; lack of these items may result in denial of the request.

Other exclusionary considerations documented on the form include absence of required clinical information (for example, missing genetic test results) and failure to meet the stated age/therapy-status requirements (such as treatment initiated prior to age 14 or appropriate documentation regarding prior gene replacement therapy status).

Requests will be considered not medically necessary when the patient cannot meet the policy's functional threshold: the form requires that the patient be able to walk independently and achieve an average distance of at least 300 meters on the 6-minute walk test (6MWT). Patients who are non-ambulatory or who record a 6MWT < 300 meters do not meet the form's initiation/restart criteria.

The form also screens for dose safety: it asks whether the patient's dose exceeds 30 mg/kg once weekly. Dosing above this threshold is not consistent with the administration parameters captured on the form and may be deemed not medically necessary.

Coding and Test Thresholds

Administration/infusion codesmixed

Administration code(s) (CPT)

Administration CPT codes to be provided on the form

Diagnosis codesICD-10

Primary ICD Code

Primary diagnosis ICD code for DMD to be supplied

inv-08: 6-Minute Walk Test — minimum average distance requirement

Minimum average distancePatient must achieve an average distance of at least 300 meters on the 6-minute walk test

Ambulation requirementMust walk independently during the 6-minute walk test (no wheelchair dependence)

Applies to initial and re-start requestsRequirement is specified for both initial therapy and re-starting therapy after gene replacement

Precertification & Provider Requirements

Prior Authorization

Prior Authorization Required

Prior authorization is required for initiation or continuation of therapy. Contact Aetna Precertification Notification to request prior authorization.

Precertification required for both initial and continuation requests
Use the completed precertification form (demographics, weight/height, prescriber/dispensing provider, product dose/frequency, and supporting clinical documentation)

Documentation Required

Infusion Site Justification

If infusion in an outpatient hospital setting is requested, document why alternate sites are not appropriate. Justify the infusion site with specific clinical details such as severe infusion reactions not responding to conventional interventions, severe venous access issues, significant behavioral or cognitive impairments without caregiver access, or medical instability (respiratory, cardiovascular, renal) that requires hospital-level monitoring and equipment.

Document adverse events or severe infusion reactions (anaphylaxis, myocardial infarction, thromboembolism, seizures) and failed conventional interventions (acetaminophen, steroids, antihistamines, fluids, slowing infusion)
Document severe venous access issues requiring special interventions only available in outpatient hospital setting
Document significant behavioral/physical/cognitive impairment impacting safety of infusion and lack of caregiver support
Document medical instability (cardiopulmonary, respiratory, renal or other) that precludes safe infusion in alternate settings

Denial Risk

Triggers for Possible Denial

Missing or insufficient documentation may lead to denial. Common triggers for possible denial include lack of genetic confirmation of Duchenne muscular dystrophy, absence of DMD gene mutation testing or mutation not amenable to exon 45 skipping, failure to meet the 6-minute walk test threshold (average ≥ 300 meters) when required, prior gene therapy without documented clinical worsening, dosing that exceeds 30 mg/kg once weekly, or incomplete precertification form.

No documented genetic confirmation of DMD
DMD mutation not identified or not amenable to exon 45 skipping
Failure to meet average 6-minute walk test distance ≥ 300 meters when applicable
Dose exceeds 30 mg/kg once weekly
Prior gene replacement therapy without documented clinical decline when applicable
Incomplete or illegible precertification form or missing supporting clinical documentation

Key Definitions

inv-14: Amenable to exon 45 skipping — definition of amenable genetic mutation

DefinitionA DMD gene mutation identified by genetic testing that is amenable (responsive) to exon 45 skipping therapy

Documentation requiredGenetic testing identifying the specific DMD gene mutation must be submitted on the form

Coverage implicationPatients whose mutation is not amenable to exon 45 skipping are excluded from coverage

inv-15: 6-minute walk test (6MWT) — definition and requirement to walk independently and achieve ≥ 300 meters

Test description6-minute walk test (6MWT) is a functional assessment of ambulatory capacity over six minutes

Independence requirementThe patient must be able to walk independently during the test

Distance thresholdAn average distance of at least 300 meters is required for consideration for initiation or re-starting of therapy

Background

Amondys 45 (casimersen) is an exon-skipping therapy indicated for patients with Duchenne muscular dystrophy whose genetic mutation is specifically amenable to exon 45 skipping. The precertification form collects confirmatory genetic testing (diagnosis and mutation type), baseline functional status including the 6-minute walk test with a minimum average of 300 meters while walking independently, prior gene replacement therapy history, and safety considerations relevant to infusion administration.

Providers must complete the form fields documenting patient demographics, prescriber/dispensing provider and place of administration, product dose and frequency, and clinical evidence (genetic test results, 6MWT, and prior therapy history) to support a request for initiation, re-start, or continuation of Amondys 45.