English appeals court overturns Regeneron transgenic mice decision

The English Court of Appeal has reversed a finding that two of Regeneron’s European patents covering transgenic mice were insufficient.

Yesterday, March 28, the court held that the specifications of European patent (UK) 1,360,287 and its divisional European Patent (UK) 2, 264,163 do disclose the claimed inventions “clearly enough and completely enough for them to be performed by a person skilled in the art”.

Both patents cover transgenic mice that can be used as a tool for experimenting with therapeutic antibodies.

More than two years ago, in February 2016, the English High Court f ound the two patents to be invalid, while rejecting Regeneron’s claims that Kymab and Novo Nordisk had infringed them.

Kymab and Novo had challenged the patents on the grounds of insufficiency, obviousness and that they were anticipated.

While Mr Justice Carr rejected the obvious and anticipated arguments, he agreed with the defendants that for claim 1 of the ‘287 patent “the skilled person would not have been able to perform the invention over the whole area claimed without undue burden and without needing inventive skill”.

Regeneron appealed against the invalidity decision, while Kymab cross-appealed against Carr’s finding that Kymab’s various strains of transgenic mice would infringe some of the patent claims if those patents had not been invalid.

Novo Nordisk did not take any active part in proceedings because Regeneron discontinued its infringement claim against it shortly before the trial. However, its counterclaim for revocation survived.

“We have come to the conclusion that claim 1 of the ‘163 patent does not exceed the contribution to the art which the disclosure of its specification has made. We are satisfied that the extent of the patent monopoly, as defined by claim 1, does correspond to that technical contribution to the art and that it is adequately enabled across its scope,” said the court.

Regeneron’s appeal was allowed and Kymab’s appeal was dismissed.

Kymab said that it was disappointed with the ruling and that it would seek leave to appeal against the decision to the UK Supreme Court.

Did you enjoy reading this story?  Sign up to our free daily newsletters and get stories sent like this straight to your inbox.

Join us at LSPN North America on April 26,  find out more here.