Summary & Overview
HCPCS Level II Q0240: Injection of casirivimab and imdevimab, 600 mg
HCPCS Level II code Q0240 designates a 600 mg dose of the combined monoclonal antibodies casirivimab and imdevimab administered by injection. This therapy has national relevance as a targeted biologic intervention used in outpatient settings for passive immunization or treatment related to specific viral illnesses. Accurate coding of this product is essential for throughput in infusion centers, billing clarity for payers, and monitoring utilization of high-cost biologic therapies. Key payers included in this analysis are Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of the code’s clinical context, typical sites of service, and payer coverage landscape. The publication also summarizes common billing considerations, available benchmarks where applicable, and recent policy or reimbursement updates that affect billing and claim adjudication for monoclonal antibody injections. Clinical context explains the product and administration setting to help revenue cycle and clinical leadership align coding, documentation, and operational workflows. Data not available in the input for specific modifiers, taxonomies, ICD-10 pairings, and related codes is noted elsewhere in the full publication.
Billing Code Overview
HCPCS Level II code Q0240 represents an injection of casirivimab and imdevimab, 600 mg. This code denotes a single billing unit corresponding to a combined monoclonal antibody therapy dose totaling 600 mg for passive immunization or treatment against applicable viral infections.
Service Type: Therapeutic monoclonal antibody injection
Typical Site of Service: Outpatient infusion or injection setting, including physician office, outpatient infusion center, or other ambulatory care locations capable of administering parenteral biologic therapies.
Clinical & Coding Specifications
Clinical Context
A typical patient is an adult with recent laboratory-confirmed SARS-CoV-2 infection who is at high risk for progression to severe COVID-19 due to age, immunocompromise, or comorbid conditions (for example, organ transplant recipient on immunosuppression, advanced chronic obstructive pulmonary disease, or uncontrolled diabetes). The patient presents to an outpatient infusion center, urgent care clinic, or emergency department within the early symptomatic window when monoclonal antibody treatment is indicated.
Workflow: after verification of eligibility and payer coverage, a qualified clinician orders Q0240 for administration of casirivimab and imdevimab, 600 mg. Nursing completes pre-infusion screening, vital signs, and consent; intravenous or subcutaneous administration is performed per product instructions; post-administration observation and documentation for infusion-related reactions are completed. Billing uses Q0240 with applicable modifier such as SH to indicate services provided to a specific beneficiary, and clinical documentation includes SARS-CoV-2 test result, risk factors, time from symptom onset, informed consent, lot numbers, and administration route and site.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
SH | Catheterization by physician other than the attending | Use when applicable per payer rules to indicate specific service circumstances; SH is listed in the provided modifiers and should be appended per payer guidance when required. |
QM | Monoclonal antibody administration by infusion | Use when a specific payer requires a monoclonal antibody administration modifier to distinguish this therapeutic administration (note: payer-specific). |
QW | Drug that is a single-source biosimilar | Use when payers require identification of specified biologic product status. |
JW | Drug amount discarded/not administered to any patient | Use when part of the vial is wasted and the discarded portion must be reported separately per payer guidelines. |
Q0 | Investigational clinical service provided in a clinical research study, non-covered | Use when the administration is part of a clinical trial and non-covered by standard benefits. |
XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | Use when the administration visit is a distinct encounter from other services on the same day. |
XS | Separate structure, a service that is distinct because it was performed on a separate anatomical site or organ system | Use when the administration is for a different anatomical site and payer requires distinction. |
XP | Separate practitioner, service performed by a different practitioner | Use when a different billing practitioner performed the infusion versus other services that day. |
59 | Distinct procedural service | Use when the monoclonal antibody administration is a distinct procedural service from other procedures billed the same day and documentation supports modifier 59 rules. |
RT | Right side | Use when laterality is required by payer and the administration site is side-specific (if applicable). |
| Taxonomy Code | Specialty | Notes |
|---|---|---|
| 208000000X | Internal Medicine | Frequently orders and coordinates outpatient monoclonal antibody therapy for high-risk adult patients. |
| 207Q00000X | Allergy & Immunology | Manages immunocompromised patients and may prescribe monoclonal antibodies. |
| 363L00000X | Emergency Medicine | Provides evaluation and administration in ED settings for eligible patients. |
| 164W00000X | Medical Oncology | Treats immunocompromised oncology patients and coordinates monoclonal antibody use. |
| 246QF0300X | Infectious Disease | Provides specialist assessment for infectious disease therapies including monoclonal antibodies. |
Related Diagnoses
| ICD-10 Code | Description | Clinical Relevance |
|---|---|---|
U07.1 | COVID-19 | Primary diagnosis indicating active COVID-19 infection for which monoclonal antibody therapy is indicated in eligible high-risk patients. |
Z20.828 | Contact with and (suspected) exposure to other viral communicable diseases | Used when exposure history accompanies risk stratification for prophylactic or early therapeutic consideration. |
Z79.82 | Long-term (current) use of systemic steroids | Identifies immunosuppressed status increasing risk of progression and supporting therapy eligibility. |
D89.9 | Disorder involving the immune mechanism, unspecified | Captures unspecified immunodeficiency or immune disorder contributing to high-risk status. |
E11.9 | Type 2 diabetes mellitus without complications | Comorbidity that increases risk for progression to severe disease and supports therapy consideration. |
Related CPT Codes
| CPT Code | Description | Relationship to This Procedure |
|---|---|---|
96365 | Intravenous infusion, for therapy, prophylaxis, or diagnosis; initial, up to 1 hour | Used for billing the infusion administration time for the initial hour when casirivimab and imdevimab are delivered intravenously. |
96366 | Intravenous infusion, each additional hour | Used if infusion extends beyond the initial hour and additional timed infusion reporting is appropriate. |
96372 | Therapeutic, prophylactic, or diagnostic injection (specify substance or drug); subcutaneous or intramuscular | Used when monoclonal antibody is administered subcutaneously or intramuscularly per product instructions and payer guidance. |
99024 | Postoperative follow-up visit, included in global service (not typically billed separately) | Not generally applicable but listed for workflow contexts where follow-up visits are part of bundled care; include only if payer allows separate billing. |
36415 | Collection of venous blood by venipuncture | Used when pre- or post-infusion laboratory monitoring requires blood draw prior to administration. |