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The U.S. wastes nearly $1 trillion annually on unnecessary health care spending that provides no added health benefit, such as prescribing a brand drug when a lower-cost brand or generic is available. Drug formularies keep prescription medications affordable while making sure patients get the medications they need.
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How We Build a Formulary
Formularies are a crucial strategy for keeping prescription drugs affordable, but only if they preserve access to the medications patients need to stay healthy.

Express Scripts develops formularies based on the following principles:

1. Our primary concern is clinical appropriateness, not drug cost.
2. The final decision for a patient’s drug therapy always rests with the physician.
3. We rely on objective evaluations from independent physicians.

To learn about how Express Scripts develops its national formularies, download our white paper: Formulary Development at Express Scripts.


For decades, Express Scripts has relied on the expertise and exemplary guidance of three distinct committees.
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Therapeutic Assessment Committee
Pharmacists and physicians who review specific medications make up our internal review team, following FDA approval using medical literature and published clinical trial data.
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National Pharmacy & Therapeutics (P&T) Committee
The P&T Committee is comprised of independent, actively practicing physicians and pharmacists who represent a broad range of specialty practice areas.
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Value Assessment Committee (VAC)
The VAC considers the drug values by evaluating the net cost, market share and utilization trends of clinically similar medications. The VAC comprises employees from formulary, product, finance, HR and clinical account teams.
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National Preferred Formulary (NPF)

Since 2014, the NPF – which now includes about 600 brand-name drugs and 99% of all generics – has excluded medications that don’t provide greater clinical value than lower-cost alternatives. Most exclusions have more affordable options and we work with physicians to prescribe those drugs for members. As we’re not owned by any drug manufacturer, our partners and patients can be sure medication decisions are based on clinical quality and cost-effectiveness. To learn about how the NPF generates significant savings, download our value report.

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National Preferred Flex Formulary

The National Preferred Flex Formulary creates a pathway to a more sustainable drug-pricing model. By giving plans and members access to authorized alternative products, Express Scripts is helping to lower out-of-pocket costs for members and reduce reliance on brand rebates.

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How the Flex Formulary works

When a manufacturer introduces an authorized, lower-cost alternative to a brand-name drug, Express Scripts evaluates it for placement on the National Preferred Flex Formulary. If appropriate, the more affordable alternative is added to the formulary and enrolled members gain immediate access to it. The more costly brand-name drug and potentially other drugs in the therapy class are then excluded from coverage.

Evernorth Digital Health Formulary (DHF)
The Evernorth digital health formulary vets every solution we include for clinical effectiveness, stringent security and privacy compliance, value, affordability, and a user-friendly experience. This helps plan sponsors ensure the safety, effectiveness, and usability of health technology tools available to their members.