CMS Proposes MFN Drug Pricing Strategy for Mandatory GLOBE and GUARD Models
The Centers for Medicare and Medicaid Services ("CMS") recently proposed GLOBE (Part B) and GUARD (Part D) mandatory drug pricing initiatives designed to incorporate a most-favored-nation ("MFN") pricing strategy, tying select drug inflation rebates to international reference prices in an effort to lower beneficiary out-of-pocket costs and Medicare spending while preserving or enhancing quality of care.
On December 19, 2025, CMS proposed two mandatory drug pricing demonstrations—GLOBE for Medicare Part B and GUARD for Medicare Part D—that would apply an MFN drug pricing strategy and tie Medicare payments for many Part B and Part D drugs to international reference prices.
Under GLOBE (Global Benchmark for Efficient Drug Pricing Model), CMS would test an alternative Part B inflation rebate calculation using manufacturer-reported or publicly available prices from economically comparable countries to establish a benchmark for certain high-cost, single-source drugs and biologics in the following therapeutic categories: oncology, rheumatology, immunology, ophthalmology, and endocrinology. CMS projects that the model will lower spending while preserving or enhancing quality of care, with exclusions for biosimilars and their reference products once a biosimilar enters the U.S. market. GLOBE would operate for five years from October 1, 2026, through September 30, 2031, with rebate invoicing and reconciliation continuing until September 30, 2033, and would encompass ~25% of Medicare fee-for-service beneficiaries in selected geographic areas. CMS indicates GLOBE applies to manufacturers, not providers, and would not qualify as an Advanced Alternative Payment Model for providers.
Under GUARD (Guarding U.S. Medicare Against Rising Drug Costs Model), CMS would test an alternative payment method for calculating inflation rebates for certain sole-source Part D drugs, likewise linking benchmarks to international drug costs in economically similar countries. GUARD would apply across varied therapeutic classes, including analgesics, anticonvulsants, antidepressants, cardiovascular agents, immunological agents, and metabolic bone disease agents. GUARD would begin January 1, 2027, and run five years through December 31, 2031, with rebate invoicing and payments continuing to 2033, covering 25% of Part D enrollees in randomly selected geographic areas.
These proposals signal heightened federal reliance on international reference pricing to address drug spending across Parts B and D. If implemented, these reforms would likely have a significant impact on gross-to-net revenue, and as a result may impact product portfolios, as well as commercial strategies. Comments to address benchmark methodology, country comparability, product inclusion criteria, and reconciliation mechanics for GLOBE and GUARD are due by February 23, 2026.