Keytruda (pembrolizumab) is one of the highest-cost oncology drugs billed to Medicare Part B. Because of its cost, claims for J9271 ↗ are heavily audited for precise unit calculations and proper wastage documentation.
Keytruda Unit Calculation (J9271)
The HCPCS code description for J9271 ↗ is "Injection, pembrolizumab, 1 mg".
Keytruda is usually supplied in single-dose vials (e.g., 100 mg). If a patient receives a 200 mg dose, you would bill exactly 200 units.
| Drug | Code | Administered Dosage | Billing Units |
|---|---|---|---|
| Keytruda | J9271 | 200 mg | 200 |
Crucial: The JW and JZ Modifiers for Wastage
Because Keytruda comes in single-dose vials, Medicare strictly enforces the use of discarded drug modifiers:
- Modifier JW: Use this on a separate line item to report the exact amount of the drug that was discarded (wasted) from a single-dose vial.
- Modifier JZ: Use this if there was zero discarded drug (the entire vial was administered). Claims without JW or JZ will be denied.
Administration and NCCI Rules
Keytruda is administered intravenously. Bill the appropriate IV infusion CPT code (e.g., 96413 ↗ for chemotherapy administration, intravenous infusion technique; up to 1 hour). Run an NCCI check to ensure your infusion codes do not clash with other services.