Background The Inflation Reduction Act′s Medicare Drug Price Negotiation Program allows the federal government to negotiate caps for select medications. These price caps may reduce revenue for the pharmacy benefit managers (PBMs) that negotiate the actual price paid for medicines in the US. To offset the resulting pressure on their profit margins, it is possible that PBMs would, in turn, increase patient′s out-of-pocket costs for medicines with capped prices. The model presented here evaluates how such increased out-of-pocket costs for the anticoagulants Eliquis (apixaban) and Xarelto (rivaroxaban) could impact patients financially and clinically. Methods Copay distributions for all 2023 prescription fills for Eliquis and Xarelto managed by the three largest PBMs were used to approximate current copay costs. Increased out-of-pocket costs were modeled as a shift of all Eliquis and Xarelto prescriptions to the highest copay tier. The known linear relationship between copay costs and treatment abandonment was used to calculate the potential resulting increase in treatment abandonment. Known rates of morbidity and mortality due to abandoning anticoagulants were used to estimate resulting increases in morbidity and mortality. Results If the three largest PBMs all shifted costs onto patients by moving all Eliquis and Xarelto prescriptions to the highest formulary tier, Tier 6, patients′ copay amount would increase by $235 to $482 million for Eliquis and $105 to $206 million for Xarelto. Such an increase could lead to 169,000 to 228,000 patients abandoning Eliquis and 71,000 to 93,000 abandoning Xarelto. The resulting morbidity and mortality could include up to an additional 145,000 major cardiovascular events and up to 97,000 more deaths. Conclusion The Medicare Price Negotiation Program could impact patients negatively if it causes PBMs to increase patients′ out-of-pocket costs for medicines. Policymakers should closely monitor changes in overall affordability, including all patient out-of-pocket expenditures, for medications in the program. Preemptive measures to ensure that the most vulnerable citizens are not placed in precarious situations leading to poorer health outcomes should be considered.

The Global Healthy Living Foundation (GHLF) relies on the activist philanthropy of our partners: academic partners, advocacy groups, corporate sponsors, foundations, and government agencies. We are grateful for their continued support of our community advocacy, education, and research efforts. A full list of GHLF partners is available at ghlf.org/partners. Robert Popovian holds stock in multiple pharmaceutical companies and serves as a consultant to pharmaceutical companies.

This modeling analysis was funded by an unrestricted grant from Pfizer Inc.

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