Teva announced today that the Supreme Court will hear its appeal in a move to delay generic competition for the drugmaker’s multiple sclerosis treatment Copaxone. Teva hopes to extend the drug’s patent life through September 2015. Its current patent for Copaxone is set to expire in May of this year.

In January FDA approved a new version of Copaxone that allows patients to take the drug three times a week rather than daily. The drugmaker, according to Reuters, says that it believes 45% of regular Copaxone patients will switch to the new form of the drug.  Leerink Partners analyst Jason Gerberry said he expects that 25% of current Copaxone patients will be switched by June, about 33% by year end and 40% in two years, also reported by Reuters.