CMS has proposed replacing the 500mg billing units used for intravenous immune globulin (IVIG) with new HCPCS codes in 100mg or 200mg units, effective January 1, 2027. Appendix A of CMS’ Q1 HCPCS Application Summary and Coding determinations document lists the specific deletions and replacements.

NHIA strongly opposes CMS’s proposed HCPCS coding and billing unit changes for immune globulin products, arguing that the changes would create significant administrative, operational, reimbursement, and patient care challenges without providing meaningful clinical or financial benefit. The comments emphasize that the proposal could disrupt patient access to life-sustaining therapies, increase claim denials and compliance risks, and require extensive system updates across providers, payors, manufacturers, and pharmacies. NHIA recommends that CMS withdraw the proposal entirely or, if changes proceed, standardize billing units across products, delay implementation by at least 18 months, provide transparent rationale for the changes, and allow overlap periods and automatic prior authorization crosswalks to minimize disruption. 

“In practice, intravenous immune globulin therapy is generally prescribed and operationalized in grams, not in fractional milligram increments,” NHIA states. “CMS should first demonstrate that a substantial and widespread billing problem exists before pursuing the changes proposed in this letter,” urges NHIA. “The current HCPCS structure functions effectively for all stakeholders.”

“This policy will touch every system and process employed by entities that provide Ig products to patients.” NHIA concludes, “CMS should abandon this proposal and work with affected stakeholders on any potential new coding changes.”

Infusion organizations are encouraged to submit individual comments to CMS at hcpcs@cms.hhs.gov.