ModifiedUnitedHealthcarePolicy CSOH2025D0105.D

Amondys 45 (Casimersen) (for Ohio Only)

State-specific UnitedHealthcare medical benefit drug policy for Amondys 45 (casimersen) applying only in Ohio; defines initial and continuation coverage criteria, unproven indications, applicable HCPCS and ICD-10 codes, dosing conformity and authorization durations.

Policy Summary

PayerUnitedHealthcare

PolicyAmondys 45 (Casimersen) (for Ohio Only)

Policy CodePolicy CSOH2025D0105.D

Change TypeRevised coverage criteria for initial therapy (added prior gene therapy branching)

Effective DateAug 1, 2025

Next Review Date

Key ActionPrior authorization requires submission of medical records confirming exon 45 amenable DMD mutation, documentation of ambulatory status, neurologist involvement, and documentation regarding prior gene therapy or documented decline after gene therapy if applicable; initial auth limited to ≤ 12 months.

POLICY UPDATE CHANGES

1Primary HCPCS code listed

1Diagnosis codes listed

12 moInitial authorization length (max)

12 moReauthorization length (max)

Coverage Summary

coverage_stance: covered_with_criteria; subject: Amondys 45 (casimersen) for Duchenne muscular dystrophy; scope_summary: State-specific UnitedHealthcare medical benefit drug policy for Amondys 45 (casimersen) applying only in Ohio; defines initial and continuation coverage criteria, unproven indications, applicable HCPCS and ICD-10 codes, dosing conformity and authorization durations.; effective_date: 2025-08-01; policy_number: CSOH2025D0105.D; note: Applies only in Ohio (state-specific policy).

Key thresholds and quick facts

Initial authorization (max)12 months

Reauthorization (max)12 months

Primary HCPCS code listed1

Diagnosis codes listed1

Ambulatory threshold (trial context)mean 6-minute walk test ≥ 300 m and ≤ 450 m

Initial Therapy Criteria

Coverage Rationale - Initial Therapy

Amondys 45 (casimersen) may be covered when ALL of the following are met:

ALL of the following

Diagnosis of Duchenne muscular dystrophy by, or in consultation with, a neurologist with expertise in the diagnosis of DMD
Submission of medical records (e.g., chart notes, laboratory values) confirming the mutation of the DMD gene is amenable to exon 45 skipping
Submission of medical records (e.g., chart notes, laboratory values) confirming that the patient is ambulatory prior to beginning Amondys 45 therapy
ONE of the following

Continuation Therapy Criteria

Coverage Rationale - Continuation Therapy

Reauthorization for Amondys 45 may be granted when ALL of the following are met:

ALL of the following

Submission of medical records (e.g., chart notes) demonstrating that the patient continues to remain ambulatory
Amondys 45 is not used concomitantly with other exon skipping therapies for DMD (e.g., Exondys 51 [eteplirsen], Viltepso [viltolarsen], Vyondys 53 [golodirsen])
Prescribed by, or in consultation with, a neurologist with expertise in the treatment of DMD
Dosing is in accordance with the United States Food and Drug Administration approved labeling

Unproven / Not Medically Necessary

ALL of the following

Amondys 45 is unproven and not medically necessary for the treatment of other forms of muscular dystrophy (e.g., Becker muscular dystrophy)

Denial Risk

Concomitant exon skipping therapies

Amondys 45 must not be used concomitantly with other exon skipping therapies for DMD. Concurrent use with exon skipping agents such as Exondys 51 (eteplirsen), Viltepso (viltolarsen), or Vyondys 53 (golodirsen) is disallowed and may result in denial of coverage.

Applicable Codes

Drug HCPCS (primary billing code)HCPCSCovered

J1426

Injection, casimersen, 10 mg

Diagnosis codes referencedICD-10

G71.01

Duchenne or Becker muscular dystrophy

Provider Actions

Prior Authorization

Prior authorization checklist

Checklist for prior authorization submissions: confirm the patient has a DMD mutation amenable to exon 45 skipping; confirm the patient was ambulatory prior to initiating Amondys 45; document that the therapy is prescribed by or in consultation with a neurologist with expertise in DMD; and if the patient previously received gene therapy (e.g., Elevidys), include records documenting clinically meaningful decline since gene therapy. Initial authorization is limited to no more than 12 months.

J1426

Documentation Required

Documentation requirement for prior gene therapy

When prior gene therapy was administered (for example, Elevidys [delandistrogene moxparvovec-rokl]), submit clinical records that document a clinically meaningful functional decline after gene replacement therapy to support coverage. Examples include loss of muscle strength or loss of a motor milestone.

Clinical Evidence

6-13ESSENCE trial population: ambulatory male patients aged 6-13 with mean 6MWT ≥300 and ≤450 m, FVC% predicted >50%, stable corticosteroid dose ≥6 months

0.81% vs 0.22%Dystrophin increase (interim): mean change baseline to week 48 casimersen 0.81% (0.93%→1.74%) vs placebo 0.22% (0.54%→0.76%); between-group difference 0.59 (p=0.004)

The pivotal evidence comes from the ongoing ESSENCE Phase III randomized, double-blind, placebo-controlled trial in ambulatory male DMD patients aged 6–13 years with out-of-frame deletions amenable to exon 45 skipping, defined in the trial by a mean 6-minute walk test ≥ 300 m and ≤ 450 m, percent predicted FVC > 50%, and stable corticosteroid dose ≥ 6 months. Interim Western blot results showed an increase in dystrophin: mean change from baseline to week 48 with casimersen was 0.81% (from 0.93% to 1.74%) versus placebo 0.22% (from 0.54% to 0.76%), a between-group difference of 0.59 (p=0.004). The indication is approved under accelerated approval with efficacy evaluated in the ESSENCE trial.

Background

Casimersen is an antisense oligonucleotide indicated under accelerated approval for treatment of Duchenne muscular dystrophy in patients with confirmed DMD gene mutations amenable to exon 45 skipping. It binds exon 45 of dystrophin pre-mRNA to induce exon skipping and production of truncated but functional dystrophin protein. The ESSENCE trial defined ambulatory eligibility as a mean 6-minute walk test ≥ 300 m and ≤ 450 m and required stable pulmonary function and corticosteroid use.

Revision History

2025-08-01revisedLatest

Revised coverage criteria for initial therapy to add requirement that ONE of: patient has not previously received gene therapy OR both prior gene therapy and documentation of clinically meaningful functional decline since gene therapy. Added explicit branching allowing prior Elevidys recipients to qualify only if medical records document clinically meaningful decline; archived previous policy version CSOH2025D0105.C

Policy Summary

PayerUnitedHealthcare

PolicyAmondys 45 (Casimersen) (for Ohio Only)

Policy CodePolicy CSOH2025D0105.D

Change TypeRevised coverage criteria for initial therapy (added prior gene therapy branching)

Effective DateAug 1, 2025

Next Review Date

On This Page

Patient has not previously received gene therapy (e.g., Elevidys [delandistrogene moxparvovec-rokl]) for the treatment of DMD

OR both of the following

Patient has previously received gene therapy (e.g., Elevidys [delandistrogene moxparvovec-rokl]) for the treatment of DMD
Submission of medical records (e.g., chart notes, laboratory values) documenting a clinically meaningful functional decline resulting from loss of muscle strength/motor ability (e.g., loss of a motor milestone) since receiving gene replacement therapy (e.g., Elevidys)

Amondys 45 is not used concomitantly with other exon skipping therapies for DMD (e.g., Exondys 51 [eteplirsen], Viltepso [viltolarsen], Vyondys 53 [golodirsen])

Prescribed by, or in consultation with, a neurologist with expertise in the treatment of DMD

Dosing is in accordance with the United States Food and Drug Administration approved labeling

Initial authorization will be for no more than 12 months

Prior Authorization

Initial prior authorization requirements

Prior authorization requires submission of medical records confirming the DMD mutation is amenable to exon 45 skipping, documentation that the patient is ambulatory prior to starting Amondys 45, evidence of neurologist involvement (prescribed by or in consultation with a neurologist with expertise in DMD), and documentation regarding prior gene therapy or documented clinically meaningful decline after gene therapy if applicable. Initial authorization will be for no more than 12 months.

J1426

Documentation Required

Documentation of prior gene therapy and functional decline

If the patient previously received gene therapy (e.g., Elevidys [delandistrogene moxparvovec-rokl]), submit medical records documenting a clinically meaningful functional decline since gene replacement therapy to support coverage. Examples of clinically meaningful decline include loss of muscle strength or loss of a motor milestone. Reference prior gene therapy (Elevidys) in the submitted records to map the documentation to the policy exception allowing coverage when decline is documented.

Prior Authorization

Reauthorization requirements

Reauthorization requires submission of medical records demonstrating the patient remains ambulatory, continued involvement of a neurologist with expertise in DMD (prescribed by or in consultation with such a neurologist), and dosing consistent with the FDA-approved labeling. Reauthorization will be for no more than 12 months.

J1426

Denial Risk

Concomitant exon skipping therapies — denial risk

Do not bill Amondys 45 concurrently with other exon skipping therapies. Use of Amondys 45 together with other exon skipping agents (e.g., Exondys 51 [eteplirsen], Viltepso [viltolarsen], Vyondys 53 [golodirsen]) is disallowed and may lead to claim denial.