To the Editor: Representatives of the American Academy of Allergy, Asthma & Immunology (AAAAI), the American College of Allergy, Asthma & Immunology (ACAAI), and the American Academy of Otolaryngic Allergy (AAOA) recently published guidance for evaluation by payers of Current Procedural Terminology (CPT) Codes 95165, 15115, and 95117 1. In this publication, the authors (including this author) used the term “dilutions” in several places to describe the serial vials prepared for the dose-escalation (build-up) phase of subcutaneous allergen immunotherapy (SCIT) as well as any additional vials that might be required for clinical reasons. Subsequent to publication, the Centers for Medicare & Medicaid Services (CMS) introduced a new administrative distinction between (1) vials prepared for the initial build-up phase of SCIT and (2) “dilutions” prepared outside that initial build-up phase (e.g., for dose adjustment after missed doses or local reactions). CMS has stated that, for purposes of Medicare coverage, only the “build-up” vials are considered separately reimbursable under CPT code 95165, whereas the “dilutions” are not. Because this administrative distinction did not exist at the time our guidance was prepared, the document employs the term “dilutions” in a broader sense that encompasses both categories. Readers should therefore interpret every reference to “dilutions,” “multiple dilutions,” or “serial dilutions” in the guidance as referring specifically to vials prepared for the build-up phase of SCIT. We are pleased to note that all seven of the Medicare Administrative Contractors (MACs) now recognize build-up phase vial preparation and provision as reasonable and necessary services billable under CPT code 95165 without differentiating it from maintenance therapy. Additionally, five of the seven MACs (CGS, National Government Services, Noridian, Palmetto, and WPS), representing 38 states and three US territories, have now published Local Coverage Articles (effective October 26, 2025) outlining documentation standards that are consistent with the recommendations in our Guidance. We believe this clarification resolves any potential ambiguity created by the post-publication change in CMS administrative terminology and reaffirms the original intent of the joint AAAAI/ACAAI/AAOA guidance 1. To summarize, vials prepared for the initial build-up phase should be labeled and billed as build-up doses, and dilutions reserved for dose adjustments. Sincerely, J. Allen Meadows, MD, FACAAI, FAAAAI On behalf of the authorship group and the AAAAI, the ACAAI, and the AAOA The author declares no conflicts of interest.
J. Allen Meadows (Tue,) studied this question.