FDA Orange Book · active-ingredient family
Metaxalone
Metaxalone: 2 brands, 8 generics; first approved Aug 30, 2002; generic available.
Generic availableHas discontinued products
Generic status & protection
Generic available: 8 ANDA applications approved.
Earliest patent expiry
Brands (NDA)
2
Generics (ANDA)
8
Listed patents
3
Next patent expiry
Feb 06, 2026
8 mo ago
Brand (NDA) products
Originator applications
- METAXALONERLDRSPRIMUS PHARMSNDA 0225032015
Approved strengths under this FDA application. Strength Dosage form Route Status TE 640MG TABLET ORAL Rx — - SKELAXINRLDKING PHARMSNDA 013217—2 strengths
Approved strengths under this FDA application. Strength Dosage form Route Status TE 400MG TABLET ORAL Discontinued — 800MG TABLET ORAL Discontinued —
Generic (ANDA) products (8)
Abbreviated applications
- METAXALONEINGENUS PHARMS LLCANDA 2138362020
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Discontinued — - METAXALONESCIEGEN PHARMSANDA 20746620202 strengths
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Rx AB 400MG TABLET ORAL Rx AB - METAXALONERISINGANDA 2087742018
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Discontinued — - METAXALONEACTAVIS LABS FL INCANDA 2036952017
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Rx AB - METAXALONELANNETT CO INCANDA 2047702016
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Rx AB - METAXALONEMOUNTAINANDA 0404862015
Approved strengths under this FDA application. Strength Dosage form Route Status TE 400MG TABLET ORAL Rx AB - METAXALONERSAMNEAL PHARMSANDA 2033992013
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Rx AB - METAXALONESANDOZANDA 0404452010
Approved strengths under this FDA application. Strength Dosage form Route Status TE 800MG TABLET ORAL Rx AB
Patent & exclusivity timeline
Protection horizon
Patent expiryExclusivity endToday
Listed patents
Orange Book patent file
| Patent | Expires | In | Type |
|---|---|---|---|
| 7122566 | 8 mo ago | U-915 | |
| 11918559 | in 13 yr | Product | |
| 12485111 | in 16 yr 10 mo | ProductU-4453 |
Approval history
FDA approval span
First approval
24 yr 6 mo ago
Most recent approval
6 yr 1 mo ago
Approvals span 2002–2020 across 10 FDA applications.
Brand (NDA) 220%
Generic (ANDA) 880%
Metaxalone: frequently asked questions
Generics, reference-listed drug, patents, and exclusivity for this active ingredient, from the FDA Orange Book.
Built directly from the FDA Orange Book data file (products, patents, and exclusivity). TE codes, RLD/RS flags, patent expirations, and exclusivity dates match the official FDA record. Listed patents reflect those the NDA holder submits under 21 U.S.C. 355 and are not exhaustive.
Related FDA reference tools
- FDA Purple BookLicensed biologics, biosimilars, interchangeables, BLA records, and exclusivity dates.
- FDA BiosimilarsFDA-approved biosimilars and interchangeable biosimilars, by reference product.
- 510(k) Predicate DatabaseSearch FDA 510(k) clearances and map predicate-device lineage.
- FDA 483 DatabaseFDA Form 483 observations and inspection records by firm, date, and citation.

