Pharmacy benefit managers act as intermediaries between insurers, pharmacies, and drug manufacturers, orchestrating formulary design, negotiating rebates, and managing pharmacy networks with aims to control costs and streamline drug distribution. Yet, despite their purported role in fostering efficiency, the concentration of market power in just three dominant PBMs raises major concerns. According to this pioneering study, published February 6, 2026 in JAMA Health Forum, the retail prescription PBM market exhibits substantial consolidation, with 40 states manifesting highly concentrated PBM participation in Medicare Part D plans, and 37 states showing comparable concentration in Medicaid managed care.

Such high levels of concentration imply that a minimal number of PBMs exert disproportionate influence over pricing strategies and access to essential pharmaceutical products. Disturbingly, 31 states bear the imprint of highly concentrated markets in both Part D and Medicaid managed care sectors simultaneously, while among these, 10 states also display significant PBM concentration within commercial insurance spheres. The implications are deeply systemic: 93% of Medicaid managed care prescriptions and a striking 75% of Part D prescriptions are dispensed in states where PBM market dominance stifles meaningful competition.

The metrics underpinning the concentration diagnoses build upon a rigorous federal antitrust framework that evaluates market share distributions and competition barriers. When a handful of PBMs consolidate control, negotiating leverage shifts dramatically in their favor vis-à-vis drug manufacturers and pharmacies. This realignment threatens to elevate out-of-pocket patient expenses by constricting price competition, limiting pharmacy choice, and constraining formulary breadth. Drug adherence and therapeutic outcomes can thus be detrimentally impacted by barriers encoded within PBM-driven policies.

Detailed analysis of state-level data uncovers the contours of these concentrated markets, offering crucial insights for regulators and policy architects. This research arrives amid escalating scrutiny of PBM practices — practices which detractors argue conceal rebate pathways, obscure true net drug prices, and incentivize formulary exclusions that may not align with clinical needs. Legislative actions enacted in congressional spending packages have begun addressing these challenges through enhanced transparency mandates and restrictions targeting PBM contracting behaviors.

Dima Mazen Qato, lead investigator and senior scholar at the USC Schaeffer Center, emphasizes the ramifications of this concentrated market power: when PBMs operate with minimal competition, their ability to dictate drug coverage policies and pharmacy access grows unchecked. Such dominance also impedes efforts to drive systemic cost reductions, as market incentives skew toward maximizing PBM revenues through complex rebate schemes rather than fostering drug affordability for patients.

The study’s implications extend beyond market structure diagnostics. They provide a vital evidentiary foundation to inform federal and state interventions designed to recalibrate PBM accountability. Proposals under consideration range from imposing robust transparency standards on PBM transactions to curbing anti-competitive contracting provisions and promoting alternative reimbursement models. Moreover, ongoing enforcement initiatives are increasingly focused on scrutinizing the extent to which concentrated PBM markets may violate antitrust laws or perpetuate unfair trade practices.

From a technical perspective, this research employs advanced market concentration indices and integrates claims data across multiple payer systems, offering a granular representation of market dynamics often obscured in aggregated federal reports. By dissecting prescription fills segmented by state and program type, the study reveals nuanced regional variations in PBM dominance, facilitating targeted policy responses that acknowledge local market conditions instead of relying on broad universal mandates.

The consequences of sustained PBM market concentration ripple through the healthcare system. Pharmacies facing restrictive PBM networks experience reduced reimbursement rates, spurring closures particularly in independent and rural settings. Patients encounter hurdles accessing preferred medications or must navigate complex prior authorization requirements that introduce delays and administrative burden. Together, these trends threaten healthcare equity and undermine efforts to optimize medication adherence — a cornerstone of effective chronic disease management.

As policymakers engage with this emerging data, the urgency to balance PBM operational efficiencies against competitive fairness has never been greater. While PBMs may theoretically deliver cost savings via sophisticated rebate negotiations, these benefits are often opaque, obscured within complex financial flows that complicate payer and patient understanding. Enhancing PBM market competition and transparency is therefore pivotal to unlocking genuine efficiencies that translate to lower drug costs and better patient outcomes.

This landmark study sets a new benchmark in analyzing pharmaceutical distribution intermediaries, illustrating that the PBM industry’s structural characteristics have profound implications beyond the traditional supply chain. Insight-driven reform efforts aligned with these findings are essential to ensuring prescription drug markets function competitively and serve the public interest, making affordable, accessible medications a reality for millions of Americans dependent on Medicare and Medicaid.

Subject of Research: Pharmacy Benefit Manager market concentration within Medicare Part D and Medicaid managed care prescription markets.

Article Title: Pharmacy Benefit Manager Market Concentration for Prescriptions Filled at Retail Pharmacies by State and Payer Type

News Publication Date: 6-February-2026

Web References:
https://jamanetwork.com/journals/jama-health-forum/fullarticle/10.1001/jamahealthforum.2025.6546

PBM Markets for Medicare Part D or Medicaid Are Highly Concentrated in Nearly Every State

Image Credits: USC Schaeffer Center for Health Policy & Economics

Keywords: Health care policy, Drug costs, Health care costs, Pharmaceuticals, Health insurance

The committee in question, known as the Advisory Committee on Immunization Practices (ACIP), is tasked with providing critical guidance on who should be vaccinated and when. Unlike the Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC), which focuses on vaccine approval, ACIP’s recommendations directly influence public health policy and vaccination programs nationwide. The study, which meticulously analyzes financial disclosures between 2000 and 2024, indicates a remarkable decline in the presence of financial conflicts that could jeopardize committee objectivity.

Financial ties between advisory committee members and pharmaceutical companies have historically raised concerns regarding undue industry influence on vaccine policymaking. This scrutiny is particularly acute given the significant public health implications of vaccination programs. Early in the 21st century, reported conflicts of interest were notably high, peaking around 43% for ACIP panelists and 27% for those on VRBPAC. Yet, this new analysis demonstrates a sustained downward trend, with recent years marked by a minimal proportion of members disclosing financial relationships that represent conflicts of interest.

An important nuance of the research is the nature of these disclosed financial ties. While some advisory committee members report receiving research grants from vaccine manufacturers, such funding is often considered less problematic than personal income streams, which include consulting fees, stock ownership, or royalties. Since 2016, less than one percent of reported conflicts involved personal income from vaccine makers, signaling a substantial reduction in the types of financial connections traditionally viewed as most concerning.

These findings reflect broader systemic efforts to diminish conflicts of interest in federal health advisory bodies. Increased transparency mandates, more stringent disclosure requirements, and rigorous recusal policies have collectively contributed to these historic lows. The FDA, for instance, has implemented regulations aimed at limiting participation by individuals with significant financial ties to industry during vaccine approval deliberations. Similarly, the CDC has promoted policies to ensure that expertise is retained on panels while minimizing potential biases.

Lead author Genevieve Kanter, an associate professor at USC’s Price School of Public Policy and a recognized expert on conflicts of interest in federal agencies, comments on the importance of interpreting these data carefully. She notes that some reported financial ties may not technically qualify as conflicts of interest under government definitions—such as general research funding not associated directly with vaccine product development—which could mean that official rates of conflict are even lower than presented. This distinction underscores the complexities involved in assessing transparency and influence.

The research arrives amid heightened political tensions surrounding vaccine policy. Senate Democrats have launched investigations into Kennedy’s abrupt dismissal of ACIP members, expressing concern over the replacement of seasoned experts with appointees known for vaccine skepticism. These developments have intensified debates about the balance between ensuring scientific integrity and addressing potential conflicts within advisory committees.

Peter Lurie, co-author and former FDA associate commissioner, emphasizes that while vigilance regarding conflicts of interest remains crucial, the data challenge narratives suggesting widespread industry capture of vaccine advisory panels. He asserts that the current evidence points to a system that has made significant progress toward mitigating financial conflicts without compromising the expertise required for sound vaccine policy recommendations.

The methodology of the study involved thorough examination of conflict of interest disclosures submitted during committee meetings operational from 2000 through 2024. The investigators employed rigorous criteria to classify disclosures, distinguishing between various forms of financial engagement. Their analysis captured temporal trends, highlighting peak conflict rates in the early 2000s and a steady decline thereafter. The report also addresses potential limitations such as variations in reporting standards between committees and the multifaceted roles of advisory panel members, who often conduct vaccine-related research as part of their academic or clinical duties.

Importantly, the study’s implications extend beyond the immediate controversy. It sheds light on the mechanisms by which federal health bodies strive to preserve trustworthiness and scientific rigor in the face of potential industry influence. The maintained low conflict rates suggest a successful, albeit ongoing, calibration of transparency policies and ethical standards. Furthermore, it reinforces the notion that expert advisory panels can operate effectively within a framework that prioritizes public health interests over private financial gain.

While Secretary Kennedy’s concerns about industry influence resonated broadly, the empirical evidence presented by the USC Schaeffer Center illustrates a more nuanced reality. Conflicts of interest are not absent but have significantly diminished, and the most worrisome financial ties—those linked to personal compensation from vaccine manufacturers—are nearly eradicated from these advisory committees. This suggests a heightened ethical environment that fosters objective and evidence-based vaccine policymaking.

Given the vital role these committees play in charting national vaccine strategies, maintaining this low-conflict status is essential. Continued vigilance, transparent reporting, and a balanced approach to managing potential conflicts will remain critical for preserving public trust. The research serves as a timely reminder that while scrutiny is warranted, assumptions about pervasive industry capture may be overstated.

As the scientific, regulatory, and public policy communities navigate the evolving landscape of vaccine advisory governance, data-driven insights such as those provided by this study are invaluable. They inform dialogue regarding best practices and reassure stakeholders that ethical frameworks within federal vaccine advisory committees have evolved and continue to function effectively.

Subject of Research: Conflicts of interest among members of federal vaccine advisory committees (CDC’s ACIP and FDA’s VRBPAC).

Article Title: Conflicts of Interest on Federal Vaccine Advisory Committees

News Publication Date: 18-Aug-2025

Web References:
http://dx.doi.org/10.1001/jama.2025.13245

Image Credits: USC Schaeffer Center for Health Policy & Economics

Keywords: Health care policy, Vaccine research, Research ethics, Regulatory policy, Public health, Immunization, Infectious diseases