What happens to a drug’s formulary tier after a patent expires in the US?
Patent expiry often changes the competitive landscape (for example, when generics can enter), but it does not automatically move a branded drug to “Tier 3.” In the US, formulary placement is decided by each insurer or pharmacy benefit manager (PBM), usually based on contracting and relative cost-effectiveness—not on patent status alone.
Why tier placement changes (or doesn’t) after patent expiry
Even after a patent expires, a drug may stay on a higher tier if:
- No generic (or preferred alternative) is available yet.
- The insurer has negotiated pricing that makes the branded product comparable to lower tiers.
- A long-acting or “authorized” product remains protected by other exclusivities (such as regulatory exclusivity), delays, or separate patents covering formulations or methods of use.
- Patient-use restrictions, step therapy, or prior authorization are used instead of changing tiers.
When do insurers move drugs to Tier 3 specifically?
Tier 3 is commonly where a plan places non-preferred brands or certain generics/alternatives depending on that plan’s structure. Many plans move to a lower tier once generics become available because they can reduce copays. But the timing varies by:
- When FDA approval and launch occur for generics/biosimilars
- The plan’s annual formulary review cycle and contract updates
- Switching policies (some plans still keep a brand temporarily to manage utilization)
Do providers control the tier, or do insurers control it?
Providers generally prescribe the medication; the insurer/PBM controls the formulary tier and the patient’s cost-sharing. So a physician does not usually “move” a drug to Tier 3 after patent expiry. Patients usually see the change first through pharmacy benefit coverage and copay updates.
What you can check if you want to know about a specific drug
To predict tier movement, check:
- Your plan’s current formulary entry for the drug and its tier
- Whether an FDA-approved generic/biosimilar is already listed and available
- Whether the plan uses preferred brand tiers vs. non-preferred brand tiers
If you share the drug name and the type of plan (employer plan, Medicare Part D, Medicaid managed care), I can help you map what usually happens to tiers for that situation.