Loading...

    Explore
    • Policy Monitoring
    • Live Policy Feed
    • Billing Codes
    • Healthcare Providers
    • Health Insurance Payers
    • States
    • Service Lines
    • Taxonomy Codes
    Lookup tools
    • Billing Code Lookup
    • CPT Modifier Lookup
    • Provider Taxonomy Code Lookup
    • Healthcare Provider & Facility Lookup
    • Health Insurance Payer Lookup
    • Payer Contact Directory

    Policy & Benchmark Tools

    • Prior Authorization Lookup
    • Coverage Criteria Lookup
    • Timely Filing Lookup
    • Billing Code Reimbursement Rates
    • Payer Comparison Dashboard
    • Facility Comparison Dashboard
    • All tools

    Company

    • About OpenPayer
    • Data Sources
    • Trek Health
    OpenPayerby Trek Health
    LinkedInYouTube

    © 2026 Trek Health. All rights reserved.

    OpenPayer is built and maintained by Trek Health.

    v1.0.31
    OpenPayerBilling CodesDrugs Administered Other than Oral MethodHCPCS hcpcs-j3399-onasemnogene-abeparvovec-xioi-gene-therapy-injection
    Ask Trek AI about this page

    HCPCS Level II J3399: Onasemnogene abeparvovec-xioi Injection

    HCPCS Level II code J3399 describes the administration of onasemnogene abeparvovec-xioi provided as a one-time high‑dose gene therapy injection (up to 5x10^15 vector genomes) for spinal muscular atrophy; service type: infusion/injection gene therapy; typical site of service: hospital outpatient department or specialized infusion/administration center where advanced biologic therapies are delivered.

    For related coverage guidance, see recent payer policy updates: Bendamustine Products Coverage Criteria, T-Cell Lymphoma Agents: Beleodaq, Istodax, Lymphir, Poteligeo, and Romidepsin, Brentuximab Vedotin (Adcetris®) Coverage Criteria.

    Customize your policy alerts

    Sign up for hcpcs J3399 policy alerts

    Get alerted when payer policies referencing J3399 are released or updated.

    Monitor payer policy activity

    Receive email alerts as soon as relevant payer policies are published or updated.

    Table of contents

    Progress1 / 6

    Explore openpayer tools

    • Billing CodesCPT, HCPCS, DRG & more
    • Reimbursement RatesCommercial vs. Medicare rate reports
    • Facility ComparisonBeds, revenue & payer mix
    • ProvidersHospitals & facilities
    • PayersPlans & market footprint
    • Taxonomy CodesNUCC specialty codes
    • ModifiersCPT modifiers & usage
    • Prior AuthorizationPA policies by payer & drug
    • Timely FilingFiling deadlines by payer
    • Coverage CriteriaMedical necessity by payer
    • Payer ContactsClaims, PA & appeals contacts
    View all tools

    Clinical & Coding Specifications

    Clinical Context

    A pediatric patient with a genetically confirmed diagnosis of spinal muscular atrophy (SMA) type 1 is scheduled for a single-dose intravenous gene replacement therapy using onasemnogene abeparvovec-xioi. The clinical workflow begins with multidisciplinary pre-treatment evaluation: neurology confirms SMA with biallelic SMN1 deletion, baseline laboratory testing (CBC, liver panel, coagulation studies), and anti-AAV9 antibody titer assessment. A weight-based dose calculation is performed to confirm the total vector genomes do not exceed the single-treatment vial limit described by J3399. Pre-medications (for example, corticosteroids) are prescribed to mitigate transaminase elevations and immune responses, and caregivers receive education on monitoring and emergency contacts.

    On the day of service the child is admitted to an outpatient infusion center or inpatient pediatric unit depending on institutional protocol and clinical status. An infusion nurse and pediatric anesthesiology or sedation team establish IV access, verify patient identity and informed consent, and administer the intravenous infusion over the recommended time with continuous monitoring of vital signs. Liver enzymes and platelets are monitored post-infusion; corticosteroid taper is followed per protocol. Follow-up visits include liver function monitoring, clinical neurology assessments, and documentation of adverse events. Billing uses J3399 for the onasemnogene abeparvovec-xioi administration, with potential addition of appropriate modifiers to indicate unusual circumstances such as distinct procedural services, service reductions, or anesthesia involvement.

    Related CPT Codes

    CPT CodeDescriptionRelationship to This Procedure
    36415Collection of venous blood by venipuncturePerformed for baseline and post-infusion laboratory monitoring (CBC, liver panel, AAV9 antibody titers).
    96365Intravenous infusion, for therapy, prophylaxis, or diagnosis; initial, up to 1 hourMay be used to bill for infusion-related nursing time if payer requires CPT-level infusion codes in addition to or separate from the drug J-code documentation.
    96366Intravenous infusion, each additional hourUsed if infusion extends beyond the initial hour and payer requires time-based infusion coding.
    36416Collection of capillary blood specimenMay be used for point-of-care testing during follow-up visits for infants.
    99214Office or other outpatient visit for the evaluation and management of an established patient, moderate complexityRepresentative E/M code for pre-treatment consults or follow-up visits with the treating pediatric neurologist or geneticist.

    Related Modifiers

    5 rows

    ModifierDescriptionWhen to Use
    26Modifier 26 (Professional Component) identifies and bills only the professional portion of a split service — the physician’s interpretation, report, and medical judgment — when the technical…- Use CPT Modifier -26 when you are billing only the professional component (PC) of a split‑bill eligible service—i.e., you performed the physician interpretation, medical judgment and prepared a…
    52Modifier ‑52 (Reduced Services) indicates that a service or procedure was partially reduced or omitted at the provider’s discretion, allowing reporting of the basic procedure number with a qualifier…- Use modifier -52 when a physician or qualified health professional electively reduces or omits part of a procedure or service (for example, performing fewer required views or omitting a portion of…
    53Modifier 53 (Discontinued Procedure) signals that a surgical or diagnostic service was begun by the physician but terminated because of extenuating circumstances that threatened the patient’s…- Use modifier -53 when a physician/qualified healthcare professional has started a surgical or diagnostic procedure (e.g., anesthesia administered, incision or scope insertion) and then discontinues…
    62Modifier 62 indicates that two surgeons function as co‑surgeons, each performing distinct parts of the same primary surgical procedure. It is appended to the primary procedure code (and any…- Use modifier -62 when two surgeons act as co‑surgeons (both primary surgeons) on a single definitive primary procedure, each performing distinct parts of the same surgical procedure (append -62 to…
    78CPT modifier -78 indicates an unplanned, related return to the operating or procedure room by the same provider during the global postoperative period. It is appended when treatment for a…- Use modifier -78 when an unplanned, related complication during the original procedure’s global postoperative period requires the patient to return to a formal operating or procedure room and the…

    Related Provider Taxonomies

    8 rows

    Taxonomy Code
    2084P0800X
    363L00000X
    364S00000X
    364SC1501X
    246RM2200X
    207QH0002X
    317400000X
    3336C0003X

    Related Payer Policy Updates

    Specialty: Hematology/Oncology1 / 3

    10 rows

    PolicyPayerEffective Date
    Bendamustine Products Coverage Criteriablue cross blue shield - tennessee2027-01-30
    T-Cell Lymphoma Agents: Beleodaq, Istodax, Lymphir, Poteligeo, and RomidepsinMass General Brigham Health Plan2027-01-04
    Brentuximab Vedotin (Adcetris®) Coverage Criteriablue cross blue shield - tennessee2026-12-31
    Pemetrexed Coverageblue cross blue shield - tennessee2026-12-31
    Tumor Treatment Fields - Medical PolicyHealth-New-England2026-12-01
    Extracorporeal PhotopheresisCigna2026-11-15
    VonvendiCigna2026-11-15
    Hematology - AphexdaCigna2026-11-15
    Extracorporeal PhotopheresisCigna2026-11-15
    Yartemlea (narsoplimab-wuug) Coverage for TA-TMANeighborhood Health Plan of Rhode Island2026-11-01

    Related Codes

    HCPCS-J0013-ESKETAMINE-NASAL-SPRAY-1MG

    HCPCS Level II J0013: Esketamine Nasal Spray, 1 mg

    HCPCS-J0120-INJECTION-TETRACYCLINE-250MG

    HCPCS Level II J0120: Injection, Tetracycline, up to 250 mg

    HCPCS-J0121-OMADACYCLINE-INJECTION-1MG

    HCPCS Level II J0121: Omadacycline Injection, 1 mg

    HCPCS-J0122-ERAVACYCLINE-INJECTION-1MG

    HCPCS Level II J0122: Injection, eravacycline, 1 mg

    HCPCS-J0129-ABATACEPT-INJECTION-10MG-PHYSICIAN-SUPERVISED

    HCPCS Level II J0129: Abatacept Injection, 10 mg

    HCPCS-J0130-INJECTION-ABCIXIMAB-10MG

    HCPCS Level II J0130: Injection abciximab, 10 mg

    HCPCS-J0131-INJECTION-ACETAMINOPHEN-10MG-PARENTERAL-ANALGESIC

    HCPCS Level II J0131: Injection, Acetaminophen 10 mg

    HCPCS-J0132-INJECTION-ACETYLCYSTEINE-100MG-INJECTABLE-MEDICATION

    HCPCS Level II J0132: Injection, Acetylcysteine 100 mg

    HCPCS-J0133-ACYCLOVIR-INJECTION-5MG

    HCPCS Level II J0133: Injection, Acyclovir 5 mg

    HCPCS-J0134-ACETAMINOPHEN-INJECTION-FRESENIUS-KABI-10MG

    HCPCS Level II J0134: Injection, Acetaminophen (10 mg)

    Showing 1–10 of 991

    • More pages

    Frequently Asked Questions

    References

    1. 1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
    2. 2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
    3. 3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.
    Published by

    Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

    Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.