In 2026, the implementation of the Inflation Reduction Act’s maximum fair prices on selected anticoagulants, combined with Part D’s benefit redesign, may increase net Part D plan financial liabilities and lead to formulary restrictions. This has broader implications for patient care. We modeled scenarios of anticoagulant formulary restrictions on treatment rates, including placement of selected therapies on the non-preferred formulary tier and the introduction of step edits. In this report, commissioned by Pfizer Inc., we discuss the following:

• Background on the likely change in payer economics for anticoagulants and possible formulary restrictions
• Methodology
• Results
• Implications for 2026 formularies
• Caveats and limitations

This report was commissioned by Pfizer, Inc.