AstraZeneca has sued Mylan for allegedly infringing its patents covering the drug Faslodex (fulvestrant).
The complaint, filed at the US District Court for the District of Delaware on August 5, was made after Mylan sought approval from the US Food and Drug Administration to produce a generic version of the breast cancer treatment drug.
The Abbreviated New Drug Application was filed before the expiration of the patents in suit, US numbers 6,774,122; 7,456,160, and 8,329,680.
Mylan notified AstraZeneca that it was seeking approval to manufacture the proposed drug on June 27.
In its notice, Mylan claimed that the patents were invalid and unenforceable and therefore would not be infringed by its proposed generic.