Romidepsin — CPB 0865 | AETNA Coverage Update

Aetna modified CPB 0865 for romidepsin (Istodax), effective September 26, 2025. Here's what billing teams need to know.

Aetna, a CVS Health company, updated its romidepsin coverage policy under CPB 0865 Aetna system on September 26, 2025. The policy covers IV administration of romidepsin billed under CPT codes 96401–96549 for chemotherapy administration. Two approved indications remain — cutaneous T-cell lymphoma (CTCL) and peripheral T-cell lymphoma (PTCL) — while more than two dozen other diagnoses stay firmly in the experimental column. If your oncology or hematology billing team handles Aetna claims for T-cell lymphoma treatment, this update needs your attention before you bill another cycle.

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Quick-Reference Table

Field	Detail Copy
Payer	Aetna, a CVS Health company
Policy	Romidepsin (Istodax) — CPB 0865
Policy Code	CPB 0865
Change Type	Modified
Effective Date	September 26, 2025
Impact Level	Medium
Specialties Affected	Hematology/Oncology, Medical Oncology, Infusion Centers
Key Action	Confirm CTCL or PTCL diagnosis codes on all romidepsin claims before billing CPT 96413 or related chemotherapy administration codes

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Aetna Romidepsin Coverage Criteria and Medical Necessity Requirements 2025

Aetna's romidepsin coverage policy under CPB 0865 is narrow on purpose. Medical necessity approval requires one of two diagnoses — and only two.

Covered indications for initial approval:

#	Covered Indication Copy
1	Cutaneous T-cell lymphoma (CTCL) — including mycosis fungoides, Sézary syndrome, primary cutaneous anaplastic large cell lymphoma, and subcutaneous panniculitis-like T-cell lymphoma
2	Peripheral T-cell lymphoma (PTCL) — per the Appendix in the full CPB 0865 policy document

That's the complete list. Every other diagnosis is experimental, investigational, or unproven in Aetna's view.

For continuation of therapy, Aetna applies a straightforward standard: the member must show no unacceptable toxicity and no disease progression on the current regimen. Your documentation needs to support both conditions clearly at each authorization renewal.

The dosing protocol tied to this coverage policy is fixed. Romidepsin — whether Istodax brand or generic — is dosed at 14 mg/m² IV over four hours on days 1, 8, and 15 of a 28-day cycle. Aetna expects cycles to repeat every 28 days as long as the patient tolerates and benefits from the drug. If your billing team sees claims submitted with a different cycle structure, flag them. Deviations from this schedule could trigger a medical necessity review or claim denial.

Prior authorization is the real gating mechanism here. Given the narrow covered indications and the relatively high cost of romidepsin infusion visits, Aetna will scrutinize both initial and continuation requests. Make sure your prior auth submissions include the specific CTCL or PTCL subtype, documented response or stability, and absence of unacceptable toxicity. Vague documentation kills these approvals fast.

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Aetna Romidepsin Exclusions and Non-Covered Indications

The experimental list in CPB 0865 is long — and some of the diagnoses on it are ones oncology practices commonly inquire about for off-label romidepsin use. Aetna draws a hard line.

Romidepsin is considered experimental, investigational, or unproven for all of the following:

The real issue here is systemic ALCL. Aetna covers primary cutaneous anaplastic large cell lymphoma under CTCL — but not systemic ALCL. That distinction matters enormously at the ICD-10 level. One wrong code and a covered patient becomes a denied claim. Your coders need to know this line.

If you treat patients with any of the diagnoses above and a clinician is requesting romidepsin, stop before you bill. An authorization denial on experimental grounds won't get overturned without a formal appeal and strong clinical literature — and Aetna's track record on experimental designations is consistent. Loop in your billing consultant or compliance officer before pursuing a case like this.

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Coverage Indications at a Glance

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Aetna Romidepsin Billing Guidelines and Action Items 2025

The effective date of September 26, 2025 is already in effect. If your team hasn't reviewed romidepsin claims against this updated policy, do it now.

Copy Action Items

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CPT, HCPCS, and ICD-10 Codes for Romidepsin Under CPB 0865

CPT Codes — Chemotherapy Administration (Related to CPB 0865)

These codes cover the administration of romidepsin. Coverage is tied to the CTCL or PTCL indication criteria in CPB 0865.

The policy provides 149 total CPT codes in the 96401–96549 range. All fall under "Other CPT codes related to the CPB" — meaning they are the administration vehicle for romidepsin, not independently covered drugs.

HCPCS Codes

The policy data lists two HCPCS codes associated with CPB 0865. The full descriptions were not included in the available policy data. Confirm the specific HCPCS codes for romidepsin — including the J-code for the drug itself — through the Aetna provider portal or your payer contract. Romidepsin reimbursement flows through the drug J-code, and you need that confirmed before billing.

ICD-10-CM Diagnosis Codes

CPB 0865 references 690 ICD-10-CM codes in scope. The full list is available through the Aetna source policy at app.payerpolicy.org/p/aetna/0865. The most relevant codes for claim approval center on:

• CTCL subtypes: mycosis fungoides, Sézary syndrome, primary cutaneous ALCL, subcutaneous panniculitis-like T-cell lymphoma
• PTCL subtypes: per the CPB 0865 Appendix

Use the most specific ICD-10-CM code available for the patient's CTCL or PTCL subtype. Aetna's system will cross-reference diagnosis against covered indications. A nonspecific T-cell lymphoma code may not map cleanly to the covered indications list and will create friction at prior auth and claim adjudication.

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