PBM Formulary Exclusions 2026
PBM Formulary Exclusions 2026
Your Medication Got Cut From the Formulary: What PBM Exclusion Lists Mean for You in 2026
5 minute read
Every year, the three largest pharmacy benefit managers publish updated exclusion lists for their standard formularies. These lists determine which drugs are covered for tens of millions of Americans. In 2026, the exclusion lists from Caremark, Express Scripts, and OptumRx grew again, collectively removing hundreds of brand-name and specialty medications from standard coverage.¹ If you have not checked whether your medication survived this year's cuts, now is the time.
This is not a glitch or an administrative error. Formulary exclusions are a deliberate, systematic process with significant financial stakes for PBMs, plan sponsors, and manufacturers. Understanding how the system works gives you more tools to navigate it when your medication ends up on the wrong side of a formulary decision.
How PBM Formulary Exclusions Work
Pharmacy benefit managers negotiate with drug manufacturers over rebates in exchange for preferred formulary placement. The more favorable the rebate a manufacturer offers, the more likely their drug is to be placed on a preferred tier or remain on the formulary at all. When a manufacturer's rebate offer does not meet the PBM's threshold, the drug can be placed on a non-preferred tier, moved to a specialty tier, or excluded from the standard formulary entirely.
Exclusion does not mean the drug is unavailable or unsafe. It means the PBM has decided the drug will not be covered under its standard formulary unless a member qualifies for an exception. Members whose plans use these standard formularies face the formulary structure their employer or insurer chose.
According to Drug Channels' January 2026 analysis of PBM exclusion lists, the three major PBMs have continued expanding their exclusion lists year over year, with notable concentrations in specialty drugs, brand-name medications with biosimilar or generic alternatives, and certain therapeutic categories where competition gives PBMs leverage.¹
Common categories affected in 2026 include humira biosimilar alternatives where specific brand biosimilars are excluded in favor of others, GLP-1 receptor agonists where some branded versions are excluded when others have better rebate arrangements, certain insulins and diabetes medications, and various brand-name medications in categories with generic equivalents.
What Happens When Your Drug Is Excluded
If your medication is on a PBM exclusion list, here is what you are likely to experience.
Your pharmacy will tell you the drug is not covered. You may receive a notice from your insurance plan. You may also get a letter suggesting an alternative medication. The alternative is typically whatever drug the PBM has in the preferred position for that therapeutic category, often a competitor product or a biosimilar.
The plan's formulary alternative may be clinically appropriate for your situation. In many cases it is. But in some situations, you may have tried the alternative before and it did not work, you may have had a side effect or adverse reaction, or your physician may have a documented clinical reason why your current medication is the right choice for you specifically.
That documented clinical reasoning is the foundation of a formulary exception request. Most plans have a process for requesting a coverage exception when a member can demonstrate medical necessity for a non-formulary or excluded drug. The key word is "documented." An exception request that simply says "my doctor prefers this drug" is unlikely to succeed. An exception request that cites specific clinical history, therapeutic failures with the preferred alternative, or published evidence supporting the requested drug has a better chance.
The Appeal Rights You Have
Federal law and most state laws give you the right to request an exception when your plan's formulary excludes a drug your physician has prescribed. For plans governed by ERISA (most employer-sponsored plans), the appeals process is governed by the plan's Summary Plan Description and federal ERISA regulations. For Medicare Part D plans, CMS has specific rules about coverage determinations, redeterminations, and independent external review.²
You have the right to request an expedited (fast-track) appeal if your health situation is urgent. For most standard formulary exclusion situations, you will file a standard formulary exception request first, and if that is denied, you can file a formal appeal.
Ask your physician to write a letter of medical necessity that is specific and evidence-based. Generic letters are often denied. A letter that addresses the plan's stated criteria, references your clinical history, and explains why the preferred alternative is not appropriate for your individual situation is significantly more likely to succeed.
Some manufacturers also have patient assistance programs or copay support programs that can help offset the cost if you end up paying out of pocket while an appeal is pending.
What This Means for You
If your medication is going to be excluded from your plan's formulary in 2026, you may have already received a notice, or you may find out at the pharmacy. Either way, here are the immediate steps.
Confirm whether your drug is excluded by calling your plan's member services or looking it up on your plan's formulary tool. Ask specifically whether it is excluded entirely or whether it is on a non-preferred tier that you can access with higher cost-sharing.
If it is excluded, ask your physician to begin documenting medical necessity now, before you run out of medication. A transition supply may be available while your exception request is processed.
File a formal formulary exception request with your plan. Keep copies of everything, note every phone call with a date and reference number, and set a calendar reminder for the decision deadline.
Ellen can help you understand your denial and build your appeal. Start here
Frequently Asked Questions
Why does my plan use PBM exclusion lists?
Most employer-sponsored health plans and many individual and Medicare plans use a pharmacy benefit manager to administer drug benefits. PBMs negotiate rebates with drug manufacturers, and formulary exclusions are one tool they use to give preferred placement to manufacturers who offer better rebate deals. The savings from those rebates may or may not flow through to members as lower premiums or cost-sharing.
If my drug is excluded, does that mean I can never get it covered?
No. Formulary exclusion means the drug is not covered under the standard formulary, but most plans have a formulary exception process. You can request an exception by demonstrating medical necessity. The success of that request depends on the strength of your physician's documentation and how well it aligns with the plan's coverage criteria.
What if I cannot afford the drug out of pocket while I wait for my appeal?
Contact the drug manufacturer directly about patient assistance programs or bridge supply programs. Many specialty drug manufacturers offer programs for patients who are in an appeal process or who cannot afford cost-sharing. Your physician's office or a specialty pharmacy may be able to help connect you with these programs.
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