Mosunetuzumab-axgb (Lunsumio) — CPB 1025 | AETNA Coverage Update

TL;DR: Aetna, a CVS Health company, modified CPB 1025 covering mosunetuzumab-axgb (Lunsumio), effective November 6, 2025. The updated coverage policy now includes three indications beyond follicular lymphoma — and your prior authorization workflow needs to reflect all four before you submit a single claim.

Aetna's Lunsumio coverage policy now covers treatment for diffuse large B-cell lymphoma, HIV-related B-cell lymphomas, and post-transplant lymphoproliferative disorders (PTLD) — all in combination with polatuzumab vedotin (HCPCS J9309) — in addition to the original follicular lymphoma indication. The primary billing code is HCPCS J9350 (mosunetuzumab-axgb, 1 mg), paired with infusion administration codes CPT 96413 through 96417. If your oncology or hematology team treats any of these patient populations, this expansion changes your reimbursement picture starting November 6, 2025.

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Quick-Reference Table

Field	Detail Copy
Payer	Aetna, a CVS Health company
Policy	Mosunetuzumab-axgb (Lunsumio) — CPB 1025
Policy Code	CPB 1025
Change Type	Modified
Effective Date	November 6, 2025
Impact Level	High
Specialties Affected	Hematology, Oncology, Infectious Disease (HIV-related lymphomas), Transplant Medicine
Key Action	Update prior authorization workflows and charge capture for J9350 and J9309 to reflect all four covered indications before submitting claims against the November 6, 2025 effective date

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Aetna Mosunetuzumab-axgb Coverage Criteria and Medical Necessity Requirements 2025

The Aetna mosunetuzumab-axgb coverage policy under CPB 1025 covers four distinct indications. Each has its own medical necessity criteria. Getting these right before you submit is the difference between clean claims and preventable denials.

Follicular Lymphoma is the original indication and the most restrictive. Aetna requires two things: the disease must have had a partial response, no response, or be relapsed or progressive — and the member must have tried at least two prior lines of systemic therapy. Both criteria must be met. Miss either one in your documentation and you will not get an approval.

Diffuse Large B-cell Lymphoma (DLBCL) or High-Grade B-cell Lymphoma is now covered as subsequent treatment for relapsed or refractory disease. There's a hard requirement here: Lunsumio must be used in combination with polatuzumab vedotin (J9309). Monotherapy in this indication does not meet medical necessity under this policy.

HIV-Related B-cell Lymphomas is a new addition worth paying close attention to. Aetna covers Lunsumio in combination with polatuzumab vedotin for four specific subtypes: HIV-related diffuse large B-cell lymphoma, primary effusion lymphoma, HHV8-positive diffuse large B-cell lymphoma, and HIV-related plasmablastic lymphoma. All must be relapsed or refractory. The specificity here matters — your diagnosis codes need to match one of those four subtypes exactly.

Post-Transplant Lymphoproliferative Disorders (PTLD) rounds out the new indications. Aetna covers subsequent treatment of relapsed or refractory monomorphic PTLD of B-cell type, again in combination with polatuzumab vedotin. If the PTLD is not monomorphic B-cell type, this policy does not apply.

Precertification is mandatory for all Aetna participating providers across applicable plan designs. Call (866) 752-7021 or fax (888) 267-3277 to initiate prior authorization. Statement of Medical Necessity (SMN) precertification forms are available through Aetna's Specialty Pharmacy Precertification portal.

Continuation of therapy requires reauthorization. Aetna approves continuation when there is no evidence of unacceptable toxicity or disease progression on the current regimen. Build that into your reauthorization documentation before the prior auth lapses.

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Aetna Lunsumio Exclusions and Non-Covered Indications

Aetna is direct about this: any indication not listed in Section I of CPB 1025 is considered experimental, investigational, or unproven. There is no gray area here. If a provider submits J9350 for an off-label use — say, an early-line follicular lymphoma patient who hasn't completed two prior therapy lines — that claim will not meet medical necessity and will face denial.

The same applies to the combination requirement. For DLBCL, HIV-related lymphomas, and PTLD, Lunsumio as monotherapy is not covered under this policy. If your charge capture bills J9350 without J9309 for those indications, expect a claim denial. Make sure your billing team knows the combination requirement isn't optional — it's a coverage condition.

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Coverage Indications at a Glance

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Aetna Lunsumio Billing Guidelines and Action Items 2025

The real issue with a policy expansion like this is the gap between what your clinical team knows and what your billing team has documented. Oncology billing for bispecific antibodies is already complex. Adding three new indications with combination requirements makes clean claim submission harder — not easier — if your workflows don't catch up to the November 6, 2025 effective date.

Here's what to do now:

Copy Action Items

If your practice manages a mix of commercial Aetna plans alongside Medicare, note that CPB 1025 applies to commercial plans only. Medicare criteria fall under separate Aetna Medicare Part B guidelines. If you're not sure which policy governs a specific patient's plan, talk to your compliance officer before the claim goes out.

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CPT, HCPCS, and ICD-10 Codes for Mosunetuzumab-axgb Under CPB 1025

Covered HCPCS Codes (When Selection Criteria Are Met)

Code	Type	Description Copy
J9350	HCPCS	Injection, mosunetuzumab-axgb, 1 mg

CPT Codes for Chemotherapy Administration

These codes support Lunsumio administration claims. Pair them with J9350 for your facility or provider-based infusion billing.

Descriptions shown as listed in CPB 1025. Refer to the AMA CPT codebook for full official descriptors.

Key ICD-10-CM Diagnosis Codes

The follicular lymphoma codes span the full C82 subcategory. The table below shows a representative range from CPB 1025.

ICD-10-CM descriptions shown as listed in CPB 1025 ("Follicular lymphoma" for all C82.x codes). Site-specific descriptions are not provided in the source policy. Refer to the official ICD-10-CM tabular list for complete descriptors.

The full ICD-10-CM code set for CPB 1025 includes 102 codes spanning the complete follicular lymphoma subcategory (C82.x), DLBCL codes, HIV-related lymphoma codes, and PTLD codes. Review the full code list in the CPB 1025 policy source to confirm all applicable diagnosis codes for your claims.

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