J9331 — Injection, sirolimus protein-bound particles, 1 mg
J9331 is a HCPCS Level II code for injection, sirolimus protein-bound particles, 1 mg. It belongs to the Drugs Administered Other Than Oral Method section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Physician fee schedule statusE
Excluded from the physician fee schedule by regulation. Payment, where it exists, comes from another fee schedule (drugs via ASP, supplies via DMEPOS, and so on).
Global period: XXX
Want the dollar amount for your locality? The fee calculator applies your GPCI and the current conversion factor.
Medically Unlikely Edits — units per day
The most units of J9331 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 300 units MAI 3 — Date of Service Edit: Clinical · Prescribing Information
- outpatient
- 300 units MAI 3 — Date of Service Edit: Clinical · Prescribing Information
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for J9331
- Long descriptor
- Injection, sirolimus protein-bound particles, 1 mg
- Short descriptor
- Inj sirolimus prot part 1 mg
- Added
- July 1, 2022
- BETOS
- O1E
- Pricing indicator
- 51 — Other
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Drugs.
Codes adjacent to J9331
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If J9331 is not quite right, the correct code is very often within a few positions of it.
- J9322Injection, pemetrexed (bluepoint), not therapeutically equivalent to j9305, 10 mg
- J9323Injection, pemetrexed ditromethamine, 10 mg
- J9324Injection, pemetrexed (pemrydi rtu), 10 mg
- J9325Injection, talimogene laherparepvec, per 1 million plaque forming units
- J9326Injection, telisotuzumab vedotin-tllv, 1 mg
- J9328Injection, temozolomide, 1 mg
- J9329Injection, tislelizumab-jsgr, 1mg
- J9330Injection, temsirolimus, 1 mg
- J9332Injection, efgartigimod alfa-fcab, 2mg
- J9333Injection, rozanolixizumab-noli, 1 mg
- J9334Injection, efgartigimod alfa, 2 mg and hyaluronidase-qvfc
- J9340Injection, thiotepa, 15 mgterminated
- J9341Injection, thiotepa (tepylute), 1 mg
- J9342Injection, thiotepa, not otherwise specified, 1 mg
- J9345Injection, retifanlimab-dlwr, 1 mg
- J9347Injection, tremelimumab-actl, 1 mg
Questions about J9331
What is HCPCS code J9331?
J9331 is a HCPCS Level II code for injection, sirolimus protein-bound particles, 1 mg. It sits in the Drugs Administered Other Than Oral Method section.
Does Medicare cover J9331?
The CMS HCPCS file marks J9331 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
How is J9331 paid under the physician fee schedule?
J9331 carries PFS status code E. Excluded from the physician fee schedule by regulation. Payment, where it exists, comes from another fee schedule (drugs via ASP, supplies via DMEPOS, and so on).