ModifiedHealth NetPolicy CP PHAR.421

Onasemnogene abeparvovec (Zolgensma) coverage

Defines medical necessity, authorization criteria, dosing, and exclusions for one-time IV administration of onasemnogene abeparvovec (Zolgensma) for pediatric patients with spinal muscular atrophy (SMA) under Health Net lines of business.

Policy Summary

PayerHealth Net

PolicyOnasemnogene abeparvovec (Zolgensma) coverage

Policy CodePolicy CP PHAR.421

Change TypeMaterial updates to approval criteria and boxed warning

Effective DateJun 7, 2019

Next Review Date

Key ActionSubmit prior authorization with documentation showing member meets all approval criteria; requests require medical director review.

SourceLink

POLICY UPDATE CHANGES

For initial approval criteria, added option of 'four copies of SMN2 gene' determined by a quantitative assay that can distinguish four from five or more copies.

Removed requirement of symptoms due to masking of symptoms with standard of care bridging therapy; allowed bridging to Zolgensma administration prior to therapy.

Updated boxed warnings description to 'serious liver injury and acute liver failure' with prescriber information.

Clarified wording on bridging therapy.

single-doseadministration policy (only one dose authorized)

<2 yrsFDA age indication

1.1e14 vg/kgmaximum total vector dose

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required baseline antibody titer

liver injuryboxed warning / serious risk

J3399HCPCS code described

Coverage and Medical Necessity Criteria

Initial Approval Criteria (excerpted)

Policy contains initial approval criteria and modifications; specific detailed clinical criteria appear elsewhere in full document.

SMN2 copy option: Initial approval criteria include option for four copies of SMN2 gene determined by a quantitative assay able to distinguish four from five or more copiesSMN2 = 4 copies by specific assay

Added in 2Q 2025 annual review

Requests for treatment will not be authorized for members with advanced SMA, defined in this policy as complete paralysis of limbs or permanent ventilator dependence. Non–FDA approved (off‑label) indications are also not authorized under this policy unless the provider supplies sufficient documentation of efficacy and safety consistent with the applicable off‑label use procedures (commercial, marketplace, or Medicaid references) and evidence of coverage criteria are met.

For members covered by Medicaid, state Medicaid coverage provisions take precedence over the provisions of this clinical policy. If state rules conflict with this policy, the state Medicaid manual and applicable state coverage requirements must be followed and may result in different authorization outcomes.

Zolgensma (onasemnogene abeparvovec‑xioi) is an AAV‑based, single‑dose gene replacement therapy; therefore, continued therapy is not authorized under this policy — only a single administration is supported.

Any lists of procedure or billing codes included in this policy are provided for informational purposes only. Inclusion or exclusion of codes does not guarantee coverage; claims may be denied if coding, coding guidance, or other policy requirements are not met.

Coding, Dose Limits, and Laboratory Thresholds

No explicit CPT/HCPCS/NDC codes listed in this sectionmixed

No codes listed

Referenced HCPCSHCPCS

J3399

Injection, onasemnogene abeparvovec-xioi, per treatment, up to Sx10^15 vector genomes

inv-09: Maximum total vector genomes

Maximum total vector genomes1.1 x 10^14 vector genomes per kilogram (vg/kg)

Dosing formatSingle-dose IV infusion over 60 minutes

Dose constraint sourcePolicy dosage and administration section specifying maximum dose

inv-10: Anti-AAV9 antibody titer requirement

Anti-AAV9 antibody titer requirementELISA binding immunoassay <1:50

Required baseline testingBaseline anti-AAV9 antibody titer must be documented prior to administration

Prior Authorization, Documentation, and Billing Requirements

Prior Authorization

Prior Authorization Required

Prior authorization required — submission of documentation showing all approval criteria are met; medical director review required.

All requests reviewed under this policy require medical director review.
Provider must submit supporting documentation (office chart notes, laboratory results, and other clinical information) demonstrating member meets all approval criteria.

Billing Rule

Billing / Coding

Prior authorization and billing code guidance. Coding inclusion does not guarantee coverage; claims may be denied if criteria not met.

Inclusion or exclusion of codes does not guarantee payment — reference professional coding guidance when submitting claims.

Clinical Background and Therapy Description

Spinal muscular atrophy (SMA) is an autosomal recessive disorder caused by bi‑allelic mutations in the SMN1 gene. Disease severity is modulated by the number of copies of the SMN2 gene: higher SMN2 copy number generally correlates with a milder phenotype. Zolgensma is an AAV9 vector‑based single‑dose gene‑replacement therapy indicated for pediatric patients younger than 2 years of age with bi‑allelic SMN1 mutations; notable risks include boxed warnings for serious liver injury and acute liver failure.

inv-27: Onasemnogene abeparvovec-xioi (Zolgensma)

Therapy descriptionAAV-based single-dose gene-replacement therapy (onasemnogene abeparvovec-xioi, trade name Zolgensma)

Clinical contextReferenced in clinical trials and guideline literature for treatment of SMA

Administration noteDesigned as a one-time IV gene-replacement treatment for eligible pediatric patients

Definitions and Clinical Measures

inv-24: Spinal muscular atrophy (SMA)

Genetic definitionSMA is an autosomal recessive disorder caused by bi-allelic SMN1 mutations on chromosome 5

SMN2 modifierSMN2 copy number modulates disease severity; higher SMN2 copies typically correlate with less severe disease

Population notes>95% of individuals with SMA retain at least one SMN2 copy; copy number distributions vary by SMA type

inv-25: CHOP-INTEND

CHOP-INTEND overview16-item, 64-point neuromuscular score validated for SMA type I

Clinical interpretationA CHOP-INTEND score >40 is considered a clinically meaningful change

Policy Summary

PayerHealth Net

PolicyOnasemnogene abeparvovec (Zolgensma) coverage

Policy CodePolicy CP PHAR.421

Change TypeMaterial updates to approval criteria and boxed warning

Effective DateJun 7, 2019

Next Review Date

Key ActionSubmit prior authorization with documentation showing member meets all approval criteria; requests require medical director review.

SourceLink

On This Page

Assay typeELISA binding immunoassay as specified in policy

inv-11: FDA age limit

FDA age indicationPediatric patients less than 2 years of age

Genetic requirementBi-allelic SMN1 mutations required per FDA indication

Implication for eligibilityPatient must be younger than 2 years at time of treatment to meet FDA indication

inv-12: SMN2 gene copy distinction

SMN2 copy option addedOption to consider four copies of SMN2 when determined by a quantitative assay that can distinguish four from five or more copies

SMN2 roleSMN2 copy number correlates with disease severity and is used in initial approval criteria

Assay requirementQuantitative assay capable of distinguishing 4 vs ≥5 SMN2 copies per policy update

Documentation Required

Concomitant Therapy / Transition

Concomitant therapy and transition requirements — Zolgensma is not to be prescribed concurrently with nusinersen (Spinraza) or risdiplam (Evrysdi). If the member has been receiving nusinersen or risdiplam prior to Zolgensma, the provider must document the clinical rationale for transition and meet the policy's bridging/transition documentation requirements.

Zolgensma cannot be used concurrently with Spinraza (nusinersen) or Evrysdi (risdiplam).
If member previously received Spinraza or Evrysdi, provider must submit documentation per policy (e.g., evidence of clinical deterioration such as sustained decrease in CHOP-INTEND over 3–6 months, and provider attestation of discontinuation when bridging to Zolgensma).

Note

Bridging Therapy Allowed

Bridging therapy allowance — standard-of-care bridging with nusinersen or risdiplam to permit eventual administration of Zolgensma is allowed. Removed requirement that bridging be justified by masking of symptoms. Providers must still submit documentation supporting the use of bridging therapy and, when applicable, evidence of clinical deterioration and plan for discontinuation of the bridge therapy prior to Zolgensma administration.

Bridging to Zolgensma from Spinraza or Evrysdi is permitted.
Documentation should include clinical rationale for bridging, timeline, evidence of deterioration if claimed, and provider attestation of discontinuation prior to Zolgensma dosing.

Baseline CHOP-INTEND score is required documentation for eligibility assessment

inv-26: HINE Section 2

HINE Section 2 descriptionStandardized motor milestone exam for infants aged 2–24 months

ScoringEvaluates seven motor milestone areas with a total maximum score of 26

Policy useBaseline HINE Section 2 motor milestone score is acceptable documentation for eligibility assessment

inv-28: SMN2 gene copy number

SMN2 copy number criterionSMN2 copy number is included in initial approval criteria; policy explicitly allows an option for 4 copies when determined by a quantitative assay that distinguishes 4 vs ≥5 copies

Clinical rationaleSMN2 copy number correlates with disease severity and informs eligibility

Documentation requirementGenetic testing quantifying SMN2 copy number must be performed using an appropriate quantitative assay