Generic entry timeline

Imitrex generics — when can they launch?

Imitrex (SUMATRIPTAN) · GSK · 6 active US patents · 3 expired

Earliest patent expiry

2030-06-16

4 years remaining

Full patent estate to

2031-07-19

complete protection through 2031

FDA approval

1992

GSK

Where Imitrex sits in the generic timeline

Mid-term cliff: earliest active US patent for Imitrex expires in 2030 (~4 years). Generic developers typically begin ANDA bioequivalence studies 3-4 years ahead of this date. Paragraph IV filings + Hatch-Waxman 30-month stays may shift the effective entry by another 18-36 months.

Under US Hatch-Waxman, a generic enters via an ANDA (Abbreviated New Drug Application) and may file with one of four Paragraph IV certifications attacking the brand's listed patents. If the brand sues within 45 days, a 30-month FDA approval stay is triggered. First Para IV filer typically gets 180-day market exclusivity.

Patent estate by type — active patents

Method-of-use patents only carve out specific indications; generics can launch with a "skinny label" omitting those uses. Composition-of-matter patents block the molecule itself.

Method of Use — 5 patents
Formulation — 1 patent

FDA U-codes carved out by Imitrex patents

Method-of-use patents are listed against specific FDA Patent Use Codes ("U-codes") representing carved-out indications. Generics can launch with a label that omits these uses.

U-code	Description
`U-1719`	(no description)

Sample patent estate

Showing 6 of 6 active US patents. View full estate on the Imitrex drug page →

US10603305 Method of Use · expires 2030-06-16

This patent protects a pharmaceutical composition for intranasal administration of sumatriptan or a related compound, providing a T max value of less than 30 minutes.

USPTO title: Formulations comprising triptan compounds
US9610280 Method of Use · expires 2030-06-16

This patent protects a pharmaceutical composition for intranasal administration of sumatriptan or a related compound, providing a certain time to peak effect.

USPTO title: Formulations comprising triptan compounds
US12090139 Formulation · expires 2030-06-16

This patent protects a pharmaceutical composition for intranasal administration of sumatriptan or a solvate thereof, with a rapid onset of action.

USPTO title: Formulations comprising triptan compounds
US9974770 Method of Use · expires 2030-06-16

This patent protects pharmaceutical compositions for intranasal administration of sumatriptan or its salts, with a rapid onset of action.

USPTO title: Formulations comprising triptan compounds
US11337962 Method of Use · expires 2030-06-16

This patent protects a pharmaceutical composition for intranasal administration of sumatriptan or a related compound, providing a Tmax value of less than 30 minutes.

USPTO title: Formulations comprising triptan compounds
US9211282 Method of Use · expires 2031-07-19

This patent protects a pharmaceutical composition for intranasal administration of sumatriptan or a related compound, providing a certain time to peak effect.

USPTO title: Formulations comprising triptan compounds

Sources

FDA Orange Book — patents listed against Imitrex (NDA filed 1992)
Imitrex drug profile — full patent estate, indications, clinical trials, pricing
GSK patent portfolio
Patent cliff 2030 — every drug losing US exclusivity that year

Patent term extensions (PTR, pediatric exclusivity), Hatch-Waxman 30-month stays, and FDA regulatory exclusivity (NCE/ODE/PED) may shift the effective generic entry date. Not legal advice.

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