Summary & Overview
HCPCS J3391: Atidarsagene Autotemcel Injection, Per Treatment
HCPCS Level II code J3391 represents the per-treatment injection of atidarsagene autotemcel, a gene therapy product administered as a single treatment episode. As a specific drug administration code, J3391 is central to billing for high-cost, one-time or limited-course gene therapy treatments and affects provider reimbursement workflows, coverage determinations, and prior authorization practices nationwide. Payers commonly involved in coverage and payment decisions include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare.
Readers will find national-level context on the clinical role of atidarsagene autotemcel, typical sites of service for administration, and the billing implications of using an HCPCS Level II drug code for a gene therapy. The publication outlines payment benchmarks, policy updates relevant to specialty drug coding, and considerations for claims processing and documentation. It also highlights common modifiers used in practice and notes gaps where input data is not available. This summary is intended to inform revenue cycle teams, coding specialists, and policy analysts about how J3391 is used in administrative and payer settings and what dimensions—coverage, coding nuance, and site-of-service—are most pertinent for national planning and operational execution.
Billing Code Overview
HCPCS Level II code J3391 describes an injection of atidarsagene autotemcel, per treatment. This item represents a single administration of a gene therapy product intended for systemic delivery via injection.
Service type: Drug administration / gene therapy infusion/injection
Typical site of service: Hospital outpatient department or specialized infusion center
Data not available in the input.
Clinical & Coding Specifications
Clinical Context
A 6-month-old infant with a confirmed genetic diagnosis of Wiskott-Aldrich syndrome (or another single-gene hematopoietic disorder approved for atidarsagene autotemcel) is scheduled for administration of J3391 (injection, atidarsagene autotemcel, per treatment). The patient presents to an outpatient hospital-based ambulatory infusion center or an inpatient transplant/oncology unit for a single-dose gene-modified autologous hematopoietic stem cell infusion.
Pre-procedure workflow includes verification of identity and informed consent, review of prior leukapheresis/collection records, confirmation of product matching (chain-of-custody), baseline vital signs and laboratory assessment (CBC, chemistry panel, infectious disease screening), and documentation of eligibility criteria and payer authorization. The cell therapy product is thawed and prepared in an appropriate sterile compounding area. The infusion is administered intravenously by an experienced infusion nurse under physician supervision with continuous monitoring for acute infusion reactions and cytokine release. Post-infusion monitoring occurs in the same setting for several hours to days depending on institutional protocol, with scheduled follow-up for graft function, immune reconstitution, and long-term surveillance for treatment response and adverse events.
Typical sites of service are outpatient hospital infusion centers and inpatient hematology/oncology or bone marrow transplant units. Common payors include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, BUCA, and Medicare. Common modifiers used in billing include 22, 52, 53, 78, 80, 82, AS, SH, and to capture unusual circumstances, reduced services, surgical team participation, or site-specific billing requirements.