Encelto Cell Gene Therapy Drug
Effective for dates of service on or after October 1, 2025, Medicare approved a cell gene therapy drug, Encelto™, when furnished in ambulatory surgical centers (ASCs) under the ASC Fee Schedule and hospital outpatient departments (HOPDs) under the Outpatient Prospective Payment System (OPPS).
This article provides billing guidance and claim submission instructions for providers administering Encelto when provided in an ASC and HOPD settings.
Part A Billing Instructions for HOPDs
For Part A claims, report the following information on the CMS-1450 claim form (UB-04) or electronic equivalent:
- HCPCS J3403 (revakinagene taroretcel-lwey, per implant) on a separate claim line
- 1 unit per implant furnished, consistent with the HCPCS code descriptor "per implant":
- Current 2026 OPPS payment is $261,579.65 per implant (1 unit).
- Note: Access Addendum B from the Quarterly Addenda Rate to locate the current fee.
- Type of bill (TOB) 0131
- Revenue code 0636 for drugs/biologicals
- Associated procedure performed for implantation (for example, the surgical implant procedure when applicable), since OPPS payment is based on the HCPCS/CPT codes reported on the outpatient claim.
Note: Add remarks on the claim indicating charges have been verified.
Payment is processed under the OPPS/APC methodology for hospital outpatient departments.
Part B Billing Instructions for ASCs
For Part B claims, report the following on the CMS-1500 claim form or electronic equivalent:
- HCPCS J3403 (revakinagene taroretcel-lwey, per implant)
- Fractional units:
- Due to system limitations, ASCs must submit multiple claims to be reimbursed.
- Modifier LU (fractionated billing):
- Report on each claim line.
- Claims for fractional units billed without modifier LU will be denied.
- Modifier 76 (repeat service or payment by the same physician or other qualified health care professional):
- Report on subsequent fractional claims to prevent denials.
- Place of service (POS) 24
- Associated procedure performed for implantation (for example, the surgical implant procedure when applicable) from the ASC Fee Schedule (ASCFS)
Understanding Fractionated Units
The Part B Medicare Claim System (MCS) limits the charge amount to be reported on a single claim to $99,999.99. As a result, providers need to divide the Medicare allowed payment for Encelto cell gene therapy into fractional units billed across multiple claims.
Submit the necessary number of claims so the combined fractional units equal one complete unit (1.0) and the total billed amount equals the Medicare allowed payment amount.
Examples:
- Medicare allowed amounts of $499,999.99 or less, submit 5 claims, each reporting 0.2 fractional units, for a total of 1.0 unit.
- Medicare allowed amounts greater than $500,000.00 require 10 claims, each reporting 0.1 fractional units, for a total of 1.0 unit.
Part B Billing Claim Example
The Medicare allowed payment amount for one complete unit (1.0) of Encelto cell gene therapy is $261,579.65.
Billing in 0.2-unit increments
- Each claim reports 0.2 units with a charge amount of $52,315.93.
- Claim 1: Report J3403 with modifier LU billed with 0.2 units = $52,315.93.
- Bill this claim with the surgical code from ASCFS.
- Claims 2, 3, 4, and 5: Report J3403 with modifiers LU, 76 billed with 0.2 units = $52,315.93.
Billing Reminders
- Bill each fractional unit on a separate claim.
- The combined fractional units billed across all claims must equal one complete unit (1.0).
- Medicare contractors will pay up to one complete unit (1.0) per HCPCS code.
- Fractional units billed in excess of one complete unit (1.0) will be denied.
Note: Access Addendum BB from the ASC Payment Rate - Addenda to locate the current fee schedule information.
References