Ibritumomab Tiuxetan (Zevalin) — CPB 0659 | AETNA Coverage Update

Aetna modified CPB 0659 for ibritumomab tiuxetan (Zevalin), effective November 27, 2025. Here's what billing teams need to know.

Aetna, a CVS Health company, updated its Zevalin coverage policy under CPB 0659 Aetna system. The revision defines two covered indications and draws a hard line around everything else. If your team bills CPT 79403 or HCPCS A9543 for radioimmunotherapy, this policy update directly affects your prior authorization submissions and claim documentation.

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Quick-Reference Table

Field	Detail Copy
Payer	Aetna, a CVS Health company
Policy	Ibritumomab Tiuxetan (Zevalin) — CPB 0659
Policy Code	CPB 0659
Change Type	Modified
Effective Date	November 27, 2025
Impact Level	Medium
Specialties Affected	Hematology/Oncology, Nuclear Medicine, Radiation Oncology, Hospital Outpatient
Key Action	Confirm your patient meets one of the two covered indications before submitting claims for CPT 79403 or HCPCS A9543

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Aetna Ibritumomab Tiuxetan Coverage Criteria and Medical Necessity Requirements 2025

Aetna's Zevalin coverage policy covers exactly two indications. Everything else is denied.

The first covered indication is relapsed or refractory, low-grade or follicular B-cell non-Hodgkin's lymphoma (NHL). Aetna considers Zevalin medically necessary for these patients. Your documentation needs to show that the disease is relapsed or refractory — not just that the patient carries an NHL diagnosis.

The second covered indication is previously untreated follicular NHL — but only for patients who achieved a partial or complete response to first-line chemotherapy. This is a consolidation use case. The patient must have responded to chemo first. No response, no coverage.

The primary billable procedure is CPT 79403, the radiopharmaceutical therapy code for radiolabeled monoclonal antibody by intravenous infusion. Pair it with HCPCS A9543 for the Yttrium Y-90 ibritumomab tiuxetan therapeutic dose (up to 40 millicuries). HCPCS A9542 covers the Indium In-111 diagnostic imaging dose used in dosimetry — that's a separate billing event.

Prior authorization is standard for high-cost radioimmunotherapy under Aetna commercial plans. Submit documentation showing the diagnosis code from the C82 family (follicular lymphoma) and clinical notes confirming relapsed/refractory status or confirmed chemotherapy response. Thin documentation is the fastest route to a claim denial on this drug.

If your patient is on Medicare, this CPB 0659 Aetna policy does not govern. Aetna's published bulletin redirects Medicare criteria to Part B step therapy guidelines. Check those separately before billing Medicare Advantage plans — the criteria may differ.

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Aetna Ibritumomab Tiuxetan Exclusions and Non-Covered Indications

Aetna is blunt on this: all other indications are considered experimental, investigational, or unproven.

That's a broad sweep. Any use case that doesn't fit the two covered indications above — diffuse large B-cell lymphoma, mantle cell lymphoma, off-label solid tumor use — gets denied. The policy data includes C22.0 (liver cell carcinoma) in the ICD-10 code set listed in the policy, but that code does not appear in a covered group. If you're seeing that code on a Zevalin claim, expect a denial.

The real risk here is billing Zevalin for any NHL subtype that isn't clearly follicular or low-grade. High-grade transformations, for example, would not meet the medical necessity criteria as written. Document the histology clearly in your prior authorization request.

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Coverage Indications at a Glance

Indication	Status	Relevant Codes	Notes Copy
Relapsed or refractory, low-grade or follicular B-cell NHL	Covered	CPT 79403; HCPCS A9543; ICD-10 C82.0–C82.19+	Prior auth required; document relapsed/refractory status
Previously untreated follicular NHL — partial or complete response to first-line chemo	Covered	CPT 79403; HCPCS A9543; ICD-10 C82.xx	Must confirm chemotherapy response before Zevalin approval
All other indications (including off-label solid tumor, high-grade NHL)	Not Covered — Experimental/Investigational	Any	Aetna will deny; no exceptions stated in policy

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Aetna Ibritumomab Tiuxetan Billing Guidelines and Action Items 2025

Copy Action Items

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CPT, HCPCS, and ICD-10 Codes for Ibritumomab Tiuxetan Under CPB 0659

Covered CPT and HCPCS Codes (When Selection Criteria Are Met)

Code	Type	Description Copy
79403	CPT	Radiopharmaceutical therapy, radiolabeled monoclonal antibody by intravenous infusion
A9543	HCPCS	Yttrium Y-90 ibritumomab tiuxetan, therapeutic, per treatment dose, up to 40 millicuries

Other CPT and HCPCS Codes Related to This Policy

These codes appear in the policy but are not the primary covered service. They support the Zevalin protocol. Review bundling and billing guidelines for your payer contract.

Key ICD-10-CM Diagnosis Codes

The policy lists 174 ICD-10-CM codes. Below are the primary follicular lymphoma codes tied to the covered indications. Use the most specific code available.

The full code set includes additional C82.xx codes through all follicular lymphoma grade and site combinations, plus related NHL subtypes. Work with your coding team to select the code that matches the pathology report exactly.

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A Note on Reimbursement and the Chemotherapy Administration Codes

The 96401–96450 series in this policy covers chemotherapy administration. Zevalin billing doesn't typically use these codes for the radioimmunotherapy infusion itself — CPT 79403 is the right code for that. The chemo admin codes are likely included because Zevalin protocols often include rituximab pretreatment. Rituximab infusion uses codes from the 96413/96415 range. Don't mix these up. Using a chemo admin code instead of 79403 for the Zevalin infusion itself is a coding error that affects reimbursement and creates audit exposure.

Blood count codes 85032 and 85049 are also listed. These cover the CBC monitoring required during Zevalin therapy. Bill them separately on the appropriate service dates with documentation showing the clinical indication.

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