Cambridge, UK-based biopharma Kymab has emerged victorious from a battle with Regeneron over patents regarding genetically modified mice.

The Supreme Court of the United Kingdom has held that all of the claims of two patents – the so-called ‘Murphy patents’ – owned by Regeneron that were asserted against Kymab are invalid.

The Court’s decision upholds the February 2016 decision of the High Court trial judge, Mr. Justice Henry Carr to revoke the claims and reverses the Appeal Court’s determination that they were valid.

In 2001, Regeneron filed patents for a new type of genetically modified mouse that included a hybrid version of the gene that produces antibodies, by combining a section of the mouse’s genetic material with a section of genetic material from a human.

The resulting mouse can be used to produce antibodies which are suitable for medical treatment in humans, but are sufficiently similar to mouse antibodies that they do not cause immunological sickness in the mouse.

In 2013, the firm then sued Kymab for infringement of its patents, as Kymab was producing its own genetically modified mice, branded Kymice, with a similar genetic structure to Regeneron’s.

However, Kymab argued that the patents filed by Regeneron were invalid because they failed to adhere to a patent law rule called sufficiency, which describes the need for documents filed with the patent to be detailed enough to enable scientifically skilled readers to recreate the invention.

The Court of Appeal found that Regeneron’s patents contained enough information to enable a skilled reader to insert some of the human material into a mouse’s genes, but not how to create a hybrid structure incorporating the full human variable region genes into the mouse’s genome.

However, it upheld the patents, ruling that there was no need for them to explain how to make the full range of mice because Regeneron’s idea was a “principle of general application”.

Kymab then appealed to the Supreme Court, which countered the Appeal Court's decision by ruling that Regeneron's patents are indeed invalid, and essentially clearing Kymab of any infringement in producing its Kymice.

“This case was a David and Goliath battle between Kymab, a British biotech pioneer, and Regeneron, one of the world’s largest biotech companies, and ultimately the Supreme Court came down on the side of Kymab – it’s a terrific result for Kymab and we’re delighted to have supported them in this hotly contested patent dispute,” said Dr Penny Gilbert, partner at leading IP law firm Powell Gilbert.

“This case raised fundamentally important questions of patent law relevant to a wide variety of innovative life science companies in the UK. The Supreme Court has confirmed that patents should not be available for inventions that are not adequately enabled. Kymab has shown tremendous resilience in defending this case since Regeneron commenced proceedings in September 2013 and we are pleased to have helped them achieve this great result.

“This means that Kymab is free to continue its work in developing therapeutic antibody products to tackle some of the world’s most challenging diseases including HIV, Ebola, malaria and cancer, and supporting COVID-19 vaccine development.

“The Supreme Court found that the product claims of the Regeneron patents were invalid as these claims were not enabled across their scope on the basis of the disclosure in the patents and that in the case of a product claim, the contribution to the art is the ability of the skilled person to make the product itself, rather than the invention. The disclosure required of the patentee must therefore be sufficient to enable the skilled person to make substantially all of the types or embodiments of products within the scope of the claim, although this does not mean that every embodiment within the scope of the claim needs to have been tried, tested and proved to have been enabled to be made.

“The judgement has profound implications, not only for the biotech and wider life sciences sector, but also for all manner of products being developed that depend on patent protection.”

“We are grateful that the Court has recognised the shortcomings of the Regeneron patents and reinforced the established law that requires that an invention is adequately enabled across its scope”, said Simon Sturge, Kymab's chief executive. “Kymab’s IntelliSelect platforms continue to generate best in class, fully human monoclonal antibodies, underpinned by our extensive IP estate.”