CMS Modified NCD 148 for Lymphocyte Immune Globulin, Anti-Thymocyte Globulin (Equine), Effective March 7, 2026 — What Billing Teams Need to Know

TL;DR: The Centers for Medicare & Medicaid Services modified NCD 148, the National Coverage Determination governing lymphocyte immune globulin, anti-thymocyte globulin (equine) coverage under Medicare, effective March 7, 2026. Here's what changes for billing teams.

This update touches a narrow but high-stakes category of biologic drugs used in renal transplant care. The CMS anti-thymocyte globulin coverage policy confirms FDA-approved equine-origin lymphocyte immune globulin as a covered Medicare benefit when used to manage renal allograft rejection episodes. The policy does not list specific CPT or HCPCS codes, which creates a documentation burden your billing team needs to address now — before a claim denial lands in your queue.

Quick-Reference Table

CMS Anti-Thymocyte Globulin Coverage Criteria and Medical Necessity Requirements 2026

NCD 148 sits in the Drugs and Biologicals benefit category. That placement matters because it means coverage hinges on FDA approval status and specific indication — not just physician order.

The Centers for Medicare & Medicaid Services covers lymphocyte immune globulin, anti-thymocyte globulin (equine) under Medicare for one approved indication: management of allograft rejection episodes in renal transplantation. That's it. The coverage policy is narrow by design. This drug class exists as an adjunct to conventional immunosuppressive therapy — steroids, anti-metabolic drugs — not as a replacement for it.

Medical necessity documentation needs to reflect that adjunctive role. If your records show anti-thymocyte globulin used as a first-line agent or without concurrent conventional immunosuppression, expect scrutiny. The policy is explicit that these preparations supplement, not replace, traditional immunosuppressive regimens.

The policy also addresses future FDA approvals. Any other lymphocyte globulin preparation the FDA approves for renal allograft rejection may be covered under Medicare. That "may be" language is intentional — future products still need to meet medical necessity criteria before Medicare reimbursement follows automatically. Watch for LCD updates from your Medicare Administrative Contractor as new products reach approval.

Prior authorization requirements are not specified within NCD 148 itself. However, your MAC may have issued additional guidance or local coverage determinations that impose prior auth requirements on this drug class. Check with your MAC directly before assuming no prior authorization is needed, especially for high-cost biologic administrations.

CMS Anti-Thymocyte Globulin Exclusions and Non-Covered Indications

NCD 148 is unusually direct about what isn't covered. Any lymphocyte immune globulin preparation that lacks FDA approval for renal allograft rejection is not a covered Medicare benefit under this policy. That includes a significant number of products currently under investigation.

Equine, lapine, and murine origin preparations are all named as under investigation. None of those investigational products qualify for Medicare coverage under NCD 148 — regardless of clinical rationale, physician intent, or hospital formulary decisions. "Under investigation" means not covered. Full stop.

NCD 148 specifies coverage only for renal transplantation. Use in other transplant settings is not addressed by this policy and should not be assumed covered under NCD 148. That's a real exposure point for transplant centers with mixed programs.

The non-covered use of these drugs as standalone immunosuppression — replacing rather than supplementing conventional agents — is another documentation trap. Make sure your clinical notes and pharmacy records show the adjunctive use pattern the policy requires.

Coverage Indications at a Glance

CMS Anti-Thymocyte Globulin Billing Guidelines and Action Items 2026

The absence of specific CPT or HCPCS codes in NCD 148 is the central billing challenge here. That's not an oversight — it reflects how CMS structured this older NCD. Your billing team carries the burden of correct code assignment and documentation linkage. Here's how to handle it.

CPT, HCPCS, and ICD-10 Codes for Anti-Thymocyte Globulin (Equine) Under NCD 148

NCD 148 does not list specific CPT, HCPCS, or ICD-10 codes. This is a documented characteristic of this NCD, not a gap in the policy update itself. The absence of a code table in the source document is intentional.

What This Means for Anti-Thymocyte Globulin Billing

You still need to assign codes. The policy establishes the coverage criteria — your billing team and your MAC determine the correct code assignment. Here's how to approach this:

• NCD 148 identifies no specific HCPCS code for lymphocyte immune globulin, anti-thymocyte globulin (equine). Work with your MAC and pharmacy billing team to determine the correct code for this product. J-codes for biologics do change, and using an outdated or incorrect code is one of the most common causes of preventable claim denial in infusion billing.
• NCD 148 specifies no ICD-10 codes. Your coding team should assign the appropriate diagnosis code based on their coding resources and MAC guidance — not from this policy document. The right level of specificity still matters for medical necessity support, so confirm your coding approach with a qualified coder or your MAC.
• If your MAC has issued an LCD that intersects with this drug class, that LCD may contain a code list. That code list would govern alongside NCD 148, not instead of it.

If you're uncertain how your current charge capture maps to NCD 148's coverage criteria, talk to your compliance officer or a billing consultant who specializes in transplant or infusion services before the effective date.