When does the Rozerem (ramelteon) patent expire in the US, and what kind of patent is it?
Rozerem’s key US patent protection is tied to patents covering ramelteon and its use/specific formulations. In general US practice, “composition of matter” patents (that cover the drug substance itself) typically control when generic versions can be marketed, unless there are later “use” or “method” patents, formulation-specific patents, or regulatory exclusivities that extend market barriers beyond the first composition patent’s expiry.
However, the exact “composition of matter” patent expiration date(s) for ramelteon in the US depend on the specific patent numbers and their granted/expiration terms (including any patent term adjustments). To answer precisely, you need the exact Rozerem US patent identifiers (or the Orange Book entry) you mean.
Which patents are composition-of-matter vs method-of-use for ramelteon?
“Composition of matter” means the patent claims the drug itself (the chemical compound or a composition containing it). For branded sleep drugs like Rozerem, additional patent families often exist that claim:
- methods of treating insomnia (method-of-use)
- specific dosing regimens
- particular formulations (e.g., tablet composition or formulation characteristics)
Even if a composition-of-matter patent expires, a later method-of-use or formulation patent can still delay generic market entry for some label indications or dosages, depending on what the generic seeks to change and whether the generic’s proposed labeling triggers those patents.
How do patent expiration and FDA exclusivity interact for Rozerem?
In the US, market timing can be affected by two different layers:
- Patent expiration (driven by patent term and any term adjustments)
- FDA exclusivity (driven by the approval pathway and exclusivity rules)
So even when the “composition of matter” patent expires, FDA exclusivity and any remaining listed use/formulation patents can still matter for when an ANDA product is allowed to be marketed.
How can I verify the exact Rozerem “composition of matter” patent expiration date?
The most reliable way is the FDA’s Orange Book entry for Rozerem (ramelteon). There you can see:
- the listed US patents by type (often including whether they are listed for composition of matter vs method-of-use)
- the listed expiration dates
- any additional exclusivity periods that apply
If you share the patent number(s) you’re looking at (or the Orange Book “patent number” and “expiration date” lines), I can tell you which are composition-of-matter and what expiration date(s) govern the ramelteon drug substance protection in the US.
What if the generic files for approval after some patents expire?
Generic entry timing usually turns on whether the ANDA can be approved without violating the still-listed patents. When some patents expire earlier than others, ANDA applicants may:
- launch “at-risk” once a blocking patent is no longer enforceable (or when a particular patent is finally cleared)
- pursue label carve-outs to avoid infringement of remaining method-of-use patents
Which route applies to ramelteon depends on the remaining patent list and what the applicant’s proposed labeling is.
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I don’t have the Orange Book patent list or specific Rozerem US patent numbers/dates in the information provided to this chat, so I can’t responsibly state an exact US “composition of matter” expiration date without guessing.
If you paste the Rozerem Orange Book “patent number(s) + expiration date(s)” lines (or the patent numbers), I’ll map which one(s) are composition-of-matter and give the precise expiration timeline you’re asking for.