The Impact of PBMs on Medicare and Medicaid: A Study Overview

A recent analysis from the USC Schaeffer Center for Health Policy & Economics underscores the dominance of three major pharmacy benefit managers (PBMs) in the Medicare Part D and Medicaid managed care retail prescription markets across most U.S. states. The study, published on February 6th in JAMA Health Forum, reveals a high concentration in these programs based on a federal antitrust index, drawing attention to PBMs' significant influence on drug prices and accessibility.

The examination of PBM market dynamics comes as regulators and industry stakeholders intensify efforts to scrutinize their impact. New legislative measures, part of a federal spending package, along with state-level regulatory compliance requirements, are targeting PBM practices to address concerns over market concentration and enhance accountability. The study, led by Dima Mazen Qato, aims to inform policy decisions affecting Medicare Part D and Medicaid service delivery.

The paper, co-authored by Yugen Chen and Karen Van Nuys, seeks to support regulatory compliance in PBM operations by contributing to current initiatives like newly enacted laws and proposed regulatory changes. These efforts highlight the necessity of transparency and accountability, particularly when PBMs dominate market conditions. For further details, the study can be accessed in JAMA Health Forum under DOI: 10.1001/jamahealthforum.2025.6546.