Currentsierra health and lifePolicy 2026D0105I

Amondys 45 (casimersen) — coverage criteria for Duchenne muscular dystrophy

Defines coverage criteria and requirements for Amondys 45 (casimersen) for treatment of Duchenne muscular dystrophy in members covered under UnitedHealthcare Commercial and Individual Exchange benefit plans.

Policy Summary

Payersierra health and life

PolicyAmondys 45 (casimersen) — coverage criteria for Duchenne muscular dystrophy

Policy CodePolicy 2026D0105I

Change TypeRevised coverage criteriaadded concomitant-use exclusion

Effective DateMay 1, 2026

Next Review Date

Key ActionSubmit prior authorization with medical records verifying DMD amenable to exon 45 skipping, ambulatory status, prescriber specialty, dosing per label, and absence of excluded concomitant therapies.

SourceLink

POLICY UPDATE CHANGES

Revised coverage criteria; added criterion requiring Amondys 45 will not be used concomitantly with Duvyzat (givinostat).

Added Application section to indicate this policy applies to UnitedHealthcare Commercial and Individual Exchange benefit plans.

12initial authorization maximum duration

12reauthorization maximum duration

J1426HCPCS code for casimersen

G71.01Diagnosis code referenced

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Coverage Criteria for Amondys 45 (casimersen)

Initial Therapy

Covered when ALL of the following are met

Initial Therapy criteria: Diagnosis of Duchenne muscular dystrophy by, or in consultation with, a neurologist with expertise in the diagnosis of DMD; submission of medical records confirming the DMD gene mutation is amenable to exon 45 skipping; and one of the following: (a) submission of medical records confirming a 6-Minute Walk Test (6MWT) ≥ 300 meters while walking independently prior to beginning Amondys 45; OR (b) submission of medical records confirming the patient is ambulatory without needing an assistive device AND one of: NSAA score > 17 OR time to rise (TTR) < 7 seconds. Additionally, the patient must either not have previously received gene therapy for DMD or, if previously treated with gene replacement therapy, have submitted medical records documenting a clinically meaningful functional decline since gene therapy. Amondys 45 must not be used concomitantly with Duvyzat (givinostat) or other exon skipping therapies (e.g., eteplirsen, viltolarsen, golodirsen); therapy must be prescribed by, or in consultation with, a neurologist with expertise in the treatment of DMD; dosing must follow the FDA-approved labeling; initial authorization up to 12 months.

Structured as combined AND/OR conditions per policy

Continuation Therapy

Covered for continuation when ALL of the following are met

Continuation Therapy criteria: Submission of medical records confirming the patient remains ambulatory without needing an assistive device; Amondys 45 is not used concomitantly with Duvyzat (givinostat) or other exon skipping therapies (e.g., eteplirsen, viltolarsen, golodirsen); prescribed by, or in consultation with, a neurologist with expertise in the treatment of DMD; dosing is in accordance with the United States FDA-approved labeling; reauthorization will be for no more than 12 months.

Continuation requires ongoing ambulatory status and absence of excluded concomitant therapies.

Unproven / Not Medically Necessary

Unproven / Not medically necessary: Use of Amondys 45 for the treatment of other forms of muscular dystrophy (e.g., Becker muscular dystrophy) is considered unproven and not medically necessary.

Amondys 45 (casimersen) must not be administered at the same time as Duvyzat (givinostat) or any other exon skipping therapies for Duchenne muscular dystrophy (for example, Exondys 51/eteplirsen, Viltepso/viltolarsen, Vyondys 53/golodirsen). This concomitant-use restriction applies to both initial and continuation therapy and is a requirement for authorization.

Use of Amondys 45 for muscular dystrophy forms other than Duchenne muscular dystrophy—such as Becker muscular dystrophy—is considered unproven and not medically necessary and is therefore not covered.

Coding and Test Thresholds

Applicable HCPCS CodesHCPCS

J1426

Injection, casimersen, 10 mg

Diagnosis CodesICD-10

G71.01

Duchenne or Becker muscular dystrophy

6-Minute Walk Test

6-Minute Walk Test threshold>= 300 meters (walking independently prior to starting Amondys 45)

Alternate ambulatory criteriaAmbulatory without assistive device plus NSAA > 17 or time to rise (TTR) < 7 seconds

Trial population mentionESSENCE trial entry criterion included mean 6MWT >= 300 m and <= 450 m

Provider Requirements, Authorization & Documentation

Prior Authorization

Prior Authorization Required

Prior authorization required. Submit medical records (e.g., chart notes, laboratory values) verifying diagnosis of Duchenne muscular dystrophy and that the DMD mutation is amenable to exon 45 skipping. Include documentation of baseline ambulatory status per criteria (e.g., 6-Minute Walk Test ≥ 300 meters while walking independently, or NSAA > 17 or time to rise < 7 seconds) as applicable. Initial authorizations are for up to 12 months.

Submit completed prior authorization request form
Attach chart notes, laboratory values, genetic testing confirming exon 45 amenability
Include baseline functional measures (6MWT, NSAA, TTR)

Step Therapy

Concomitant Therapy Restriction

Do not submit Amondys 45 for concurrent use with Duvyzat (givinostat) or with other exon skipping therapies for DMD (for example, Exondys 51, Viltepso, Vyondys 53). Concomitant use is not allowed and will result in denial of the request.

Prohibited concurrent therapies: Duvyzat (givinostat); other exon skipping therapies (eteplirsen, viltolarsen, golodirsen)

Background

Duchenne muscular dystrophy (DMD) is an X-linked degenerative neuromuscular disorder that leads to progressive skeletal and cardiac muscle weakness, declining pulmonary function, and early disability. Casimersen (Amondys 45) is an antisense oligonucleotide indicated for patients with DMD who have a confirmed mutation amenable to exon 45 skipping. Treatment with Amondys 45 is subject to specific coverage criteria including documentation of the qualifying genetic mutation and ambulatory function, adherence to FDA dosing, prescriber specialty requirements, and the exclusion of concomitant exon skipping agents such as Duvyzat and other listed therapies.

Key Definitions

Amenable to exon 45 skipping

DefinitionPresence of a confirmed DMD gene mutation that can be targeted so exon 45 is skipped during pre-mRNA splicing to produce functional dystrophin

Documentation requiredSubmission of medical records confirming the DMD mutation is amenable to exon 45 skipping

Regulatory indicationAmondys 45 (casimersen) is indicated for DMD patients with a confirmed mutation amenable to exon 45 skipping (FDA accelerated approval)

Clinical trial contextESSENCE trial enrolled ambulatory patients with out-of-frame deletion mutations amenable to exon 45 skipping