Amgen filed a lawsuit in US district court of Dalaware against sanofi and Regeneron pharmaceuticals . They allegedly infringed US patent rights with patent numbers 8563698,8829165,8859741. These patents are owned by Amgen which describe and claim monoclonal antibodies to pro-protein convertase subtilisin/kexin type 9 {PCSK9}. With this lawsuit Agmen wants injunction to prevent infringing sale of Alirocumab,a monoclonal antibody targeting pcsk9 from Regeneron pharmaceuticals as they recently announced seeking regulatory approval for marketing alirocumab in US