Sanofi sues Eli Lilly to halt Lantus biosimilar

French pharmaceutical company Sanofi has sued Eli Lilly for infringing seven patents that cover its blockbuster diabetes drug Lantus (insulin glargine).

Eli Lilly had filed a New Drug Application with the US Food and Drug Administration for approval to make and sell an insulin glargine product for injection, called Abasria.

Sanofi’s Lantus is the world’s biggest selling diabetes drug, and generated sales of $7.8 billion in 2013. It is due to lose patent protection in February next year.

In the case, filed on July 7 at the US District Court for the District of Delaware, Sanofi argued that Eli Lilly’s generic product infringes patents that cover insulin preparations and the devices used to administer them in the Lantus product.

It asked for judgment that Eli Lilly has infringed each of the seven patents, and for a preliminary injunction enjoining Lilly from selling its rival product in the US.

In January, Sanofi filed a similar case against Eli Lilly in relation to the same product, but with a narrower scope.

A spokesperson for Eli Lilly said: “We are reviewing the lawsuit, however, Lilly does not believe the application infringes any of the asserted patents.”

Sanofi did not respond immediately to a request for comment.