US FDA rejects Teva's second try to block generic Copaxone; Shire sues Actavis over Intuniv

The US Food and Drug Administration has rejected a second Citizen Petition from Israel-based Teva Pharmaceutical Industries seeking to block approval of generic versions of Copaxone (glatiramer acetate), for multiple sclerosis.

According to the FDA, Teva, the world's largest generics company, asserted that it is not possible for the sponsor of an Abbreviated New Drug Application to show that a generic has the same active ingredient because neither Copaxone nor any significant subset of its polypeptides has been fully characterized, and because it is unknown which of the polypeptides are clinically active and responsible for its therapeutic effects.

The agency did say that the petition will inform its assessment of what evidence would be sufficient to show that the active ingredient in a proposed generic product is the same as that in Copaxone. Last year, the FDA denied a 2008 Citizen's Petition from Teva that sought to block approval of generic versions of Copaxone, a selective major histocompatibility complex (MHC) class II modulator.