UPDATE 1-Shire files lawsuits over Vyvanse against Sandoz

* Challenge to first application for generic version of ADHD drug (Adds details)

LONDON, July 1 (Reuters) - Pharmaceutical firm Shire said on Friday it was challenging an application from drugmakers Sandoz and Amneal to launch a generic version of its top-selling hyperactivity drug Vyvanse.

Shire said it had filed lawsuits against the companies for infringements of Vyvanse patents.

The company received notice from Sandoz, the generic arm of Swiss drugs company Novartis (NOVN.VX), in May regarding a filing of an application to the U.S. drugs regulator for the first generic version of the ADHD medicine.

Shire said in May that Vyvanse was protected by 16 patents, all of which expire in 2023. (Reporting by Paul Sandle)