The Middleman Who Sets the Price at Each End of a Prescription
Pharmacy benefit managers negotiate drug prices for insurers and reimburse pharmacies. Earning a margin on the gap between those two numbers is a business model with an obvious conflict.
What the Intermediary Does
A pharmacy benefit manager sits between the parties in prescription drug distribution. It negotiates with manufacturers over prices and rebates, builds the list of covered drugs that determines what a plan will pay for, contracts with pharmacies to dispense, processes claims, and administers the benefit for the insurer or employer that hired it.
The original rationale is genuine. A single employer has no negotiating power against a drug manufacturer. An intermediary aggregating millions of covered lives does, and it also supplies claims infrastructure that individual plans could not build.
The intermediary was created to negotiate on behalf of payers. Its revenue model determines whether its interests actually align with theirs.
The Three Revenue Streams
Understanding the controversy requires separating how these firms earn money.
| Source | Mechanism |
|---|---|
| Administrative fees | Charged to the plan for processing and services |
| Rebates | Manufacturer payments for preferred formulary placement |
| Spread | Difference between plan charge and pharmacy reimbursement |
The first is uncontroversial. The second and third are where the structural problems sit.
Spread Pricing
Spread pricing is the practice of charging the health plan one amount for a prescription and reimbursing the dispensing pharmacy a lower amount, retaining the difference.
The plan sees what it paid. The pharmacy sees what it received. Historically neither could see the other figure, so the size of the spread was visible only to the intermediary that set both.
The conflict is direct: the intermediary is paid more when the plan pays more, while its stated role is to reduce what the plan pays. On generic drugs, where acquisition costs are low and variable, spreads have in documented cases been very large as a percentage of the underlying cost.
The response has been a shift toward transparent or pass through contracts, where the plan pays exactly what the pharmacy receives plus a disclosed administrative fee. Several state Medicaid programmes prohibited spread pricing outright after audits revealed its scale.
Rebates and the Gross to Net Problem
The rebate mechanism produces its own distortion. Manufacturers pay rebates to secure preferred placement on a formulary, and those rebates are typically calculated as a percentage of the drug list price.
This creates an incentive that runs against the stated purpose. A higher list price supports a larger rebate, so both manufacturer and intermediary can prefer a high list price with a large rebate over a low list price with none, even though the net cost is similar.
The consequence falls on specific patients. Coinsurance and deductibles are frequently calculated on list price rather than net price, so a patient with a high deductible pays a percentage of a number that nobody in the supply chain actually pays. The gap between list and net has widened substantially for many drug classes, and this is the mechanism.
Concentration and Integration
Two structural features intensify the concerns. The market is highly concentrated, with a small number of firms administering benefits for most covered lives, which limits the ability of plans to negotiate or switch.
These firms are also vertically integrated with insurers, and in some cases with pharmacies and providers. An organisation that owns the insurer, the benefit manager and the pharmacy is negotiating with itself at several points, and the internal allocation of margin between those units is not externally visible.
Independent pharmacies have been particularly vocal, arguing that reimbursement rates set by an intermediary affiliated with a competing pharmacy chain create an obvious conflict.
Where Reform Is Heading
Policy attention has focused on a few specific mechanisms rather than on the existence of the intermediary. Transparency requirements would disclose the spread and the rebate flows. Pass through contracting removes spread pricing. Delinking compensation from list price would remove the rebate incentive toward higher prices. Fiduciary obligations would require the intermediary to act in the plan interest.
The counterargument from the industry is that aggregated negotiation genuinely reduces drug costs, and that removing rebate leverage would raise net prices. That claim is contested and difficult to test, because the underlying contracts are confidential.
The Bottom Line
Pharmacy benefit managers perform a real function and earn money in ways that can conflict with it. Spread pricing pays the intermediary more when the plan pays more, and percentage based rebates reward higher list prices, which patients with deductibles pay against directly. The reform direction is not to remove the intermediary but to change how it is paid, moving toward disclosed pass through pricing and compensation that does not rise with the price of the drug.