Pozen and GlaxoSmithKline (GSK), the holder of the New Drug Application for Treximet, received a letter from Par Pharmaceutical, Inc (Par) notifying Pozen and GSK that Par submitted an Abbreviated New Drug Application (ANDA) to the US Food and Drug Administration (FDA) for approval to market sumatriptan 85 mg/naproxen sodium 500 mg tablets, a generic version of the drug sold by GSK under the trade name, Treximet. Par's letter advised Pozen and GSK that it intended to market a generic version of Treximet tablets before the expiration of US Patent Nos 6,060,499, 6,586,458 and 7,332,183.

Par's letter also provided notice to Pozen and GSK that its ANDA contains a certification as required under 505(j)(2)(A)(vii)(IV) of the Federal Food, Drug and Cosmetic Act, commonly referred to as a 'paragraph IV certification'. Generally, such a certification states that the ANDA applicant believes that the claims of a patent to which a paragraph IV certification is made do not properly prevent that ANDA applicant from commercializing the product that is the subject of its ANDA. When an ANDA contains a paragraph IV certification, notice of that certification must be provided to each owner of the patent that is the subject of the certification and to the holder of the approved NDA (in this case, GSK) to which the ANDA refers.

GSK and Pozen are evaluating Par's letter and paragraph IV certification. Pozen has full confidence in its intellectual property portfolio related to Treximet and will vigorously defend its patents if they are infringed.

Pozen is a pharmaceutical company committed to developing therapeutic advancements for diseases with unmet medical needs where it can improve efficacy, safety, and/or patient convenience.