The UK Court of Appeal has recently handed down its judgement in Regeneron Pharmaceuticals Inc & Bayer AG v Genentech Inc.

The judgement confirms that the claims of Genentech’s patent EP1238986 are novel and inventive and that the invention is sufficiently disclosed.

The Court of Appeal also confirmed that the claims encompass Regeneron’s ‘VEGF-Trap’ product for treatment of macular degeneration.

Background

Genentech’s patent EP1238986 relates to the use of human vascular endothelial growth factor (hVEGF) antagonists for the treatment of non-cancerous (non-neoplastic) diseases characterised by excessive blood vessel growth (neovascularisation or angiogenesis).

The main claim (in the ‘Swiss’ format) is directed to: “Use of a hVEGF antagonist in the preparation of a medicament for the treatment of a non-neoplastic disease or disorder characterised by undesirable excessive neovascularisation, wherein the hVEGF antagonist is: (a) an anti-VEGF antibody or antibody fragment; (b) an anti-VEGF receptor antibody or antibody fragment; or (c) an isolated hVEGF receptor.”

Regeneron and Bayer sought to invalidate the patent on the grounds in an attempt to clear the way for launch of Regeneron’s VEGF-Trap product in the UK (VEGF-Trap is a chimeric molecule containing two fragments from VEGFR receptors, linked to the constant region of human immunoglobulin).

Regeneron and Bayer also sought a declaration that the product did not, in any case, infringe the patent. Genentech counter-claimed for infringement of EP1238986 by the VEGF-Trap product.

Patentability

The Court of Appeal held that the first instance judge had been right to conclude that the claims were novel and inventive in view of the prior disclosure of an antibody to VEGF which was said to have possible “therapeutic potential” (but without specifically identifying any particular medical use).

They agreed that, at the filing date, it would not have been known which, if any, of the many known angiogenic growth factors represented a suitable target to treat pathologicalconditions involving neovascularisation.

The step of trying to use VEGF antagonists for this purpose would therefore not have been undertaken by the skilled team with any real expectation of success, and the claimed use was therefore not obvious.

Sufficiency

The Court of Appeal agreed that first instance judge had been right to conclude that the patent discloses a principle of general application, namely that neovascular diseases are linked by the common thread of angiogenesis; that VEGF is necessary for pathological angiogenesis; and that it was reasonable to predict that a strategy for treating excessive angiogenesis in neoplastic diseases would also be effective to treat such angiogenesis in non-neoplastic diseases.

They also rejected suggestions by Regeneron and Bayer that the claims required the VEGF antagonists to be suitable for treatment of all aspects of the recited diseases, in all patients.

They also rejected the suggestion that it was insufficient insofar as it covered variants which were not yet developed at the filing date of the patent, stating that:

“A claim for an invention of broad application may properly encompass embodiments which may be provided or invented in the future and which have particularly advantageous properties, provided such embodiments embody the technical contribution made by the invention.

They therefore concluded that the breadth of the claims was justified by the contribution to the art made by the invention and that the patent was sufficiently disclosed.

Infringement

The Court of Appeal agreed with the first instance judge that the phrase "hVEGF receptor" includes variants of naturally occurring receptors which retain the ability to bind VEGF.

According to the Court, VEGF-Trap as a whole is effectively a variant of two VEGF receptors (flt-1 and flk-1) which retains the ability to bind VEGF and inhibit its biological activity. They concluded that it therefore falls within the scope of the claims of EP1238986.

The full Court of Appeal judgement can be read here.