Vitamin B-12 Therapy — CPB 0536 | AETNA Coverage Update

Aetna modified CPB 0536 covering Vitamin B-12 therapy, effective September 26, 2025. Here's what billing teams need to do.

Aetna, a CVS Health company, updated its Vitamin B-12 therapy coverage policy under CPB 0536, with changes effective September 26, 2025. The policy governs medical necessity criteria for injectable B-12 — specifically HCPCS J3420 (cyanocobalamin injection, up to 1,000 mcg) and J3425 (hydroxocobalamin injection, 10 mcg) — along with supporting codes for homocysteine testing (CPT 83090). This update also folds in a broad set of oncology diagnoses tied to pemetrexed chemotherapy, which requires B-12 supplementation as part of the treatment protocol.

Quick-Reference Table

Aetna Vitamin B-12 Therapy Coverage Criteria and Medical Necessity Requirements 2025

The Aetna Vitamin B-12 therapy coverage policy under CPB 0536 ties coverage directly to documented medical necessity. The specific medical necessity criteria are defined within CPB 0536 — your billing team should review the full policy text directly to confirm covered indications before submitting claims.

What the policy does make explicit is the link between B-12 supplementation and pemetrexed (Alimta) chemotherapy. For oncology patients on pemetrexed, B-12 injections are a clinical requirement — not optional supportive care. The policy maps this coverage to specific cancer diagnoses including non-squamous non-small cell lung cancer (ICD-10 C33–C34.92), mesothelioma of the pleura (C45.0), peritoneal mesothelioma (C45.1), malignant neoplasm of the thymus receiving pemetrexed (C37), and a wide range of urothelial, ovarian, and corpus uteri cancers receiving pemetrexed.

CPT 83090 (homocysteine) is covered when selection criteria are met. Elevated homocysteine is a clinical marker for B-12 deficiency, so this test often appears in the workup before initiating injection therapy. If you're billing 83090, make sure the clinical documentation supports why the test was ordered — not just that it was run.

CPT 96372 appears in this policy as a related reference code, not a covered code under CPB 0536. It's listed for context. Don't assume it carries independent coverage under this policy.

This policy does not include prior authorization guidance. Verify PA requirements directly with Aetna for the member's specific plan — especially for patients receiving ongoing B-12 injections.

Aetna Vitamin B-12 Therapy Exclusions and Non-Covered Indications

CPT 64450 — injection of anesthetic agent and/or steroid into other peripheral nerve or branch — appears in the policy as a related code, but it is not covered under CPB 0536. It's listed as a reference code, not a covered service. Don't bundle it into B-12 injection claims or use it as an alternative billing path.

B-12 injections without a covered diagnosis or qualifying condition are not covered. If the clinical notes don't support the indication spelled out in CPB 0536, expect a claim denial. Review the full policy text to confirm your documentation meets Aetna's stated criteria.

Coverage Indications at a Glance

Aetna Vitamin B-12 Therapy Billing Guidelines and Action Items 2025

These are direct steps your billing team should take before the September 26, 2025 effective date.

CPT, HCPCS, and ICD-10 Codes for Vitamin B-12 Therapy Under CPB 0536

Covered HCPCS Codes (When Selection Criteria Are Met)

Covered CPT Code (When Selection Criteria Are Met)

Key ICD-10-CM Diagnosis Codes

This policy references 473 ICD-10-CM codes. The table below covers the primary groupings. For the full list, review CPB 0536 directly.