Regeneron Pharmacueticals Inc v Genentech Inc

For infringement, a claim to an isolated VEGF receptor includes receptor fragments and variants of any size, provided they retain the essential ability to bind VEGF and inhibit its biological activity. The court must construe the claim first and then ask whether the alleged product falls within that construction; the inventive route or effort involved in making it is irrelevant.

For novelty of a therapeutic-use claim, a prior publication must disclose the therapeutic effect or give clear and unmistakable directions to use the product in therapy. A statement of possible therapeutic potential is only a signpost. For obviousness, the claimed use must have been obvious, and an obvious-to-try argument requires a fair expectation of success in that use.

Regeneron Pharmaceuticals Inc and Bayer Pharma AG sought revocation of European Patent (UK) No 1 238 986 and declarations of non-infringement concerning VEGF Trap Eye, an ophthalmic VEGF antagonist. Genentech Inc counterclaimed for infringement.

The patent claimed the use of VEGF antagonists, including isolated VEGF receptors, in treating non-neoplastic diseases characterised by undesirable excessive neovascularisation. The issues were construction, infringement, novelty over Kim 1992, obviousness, and sufficiency across the claimed diseases and antagonists.

1. Construction and infringement. The relevant diseases were those characterised by excessive and undesired angiogenesis. The claim did not require the angiogenesis to be causative of the disease, to be VEGF-mediated, or for the treatment to address aspects of the disease independent of angiogenesis. An isolated VEGF receptor included fragments and variants, without limitation to the complete extracellular domain, provided that they retained the essential ability to bind hVEGF and inhibit its biological activity.
2. The court was required to determine infringement by applying the properly construed claims. It was irrelevant whether the particular construct was contemplated by the patentee or required a substantial research effort. VEGF Trap Eye bound VEGF sufficiently to produce a therapeutic effect and fell within the claim.
3. Novelty. Under Patents Act 1977, s 2, anticipation required disclosure and enablement. Applying the principles in Synthon v SKB and General Tire and Rubber Co v Firestone Tyre and Rubber Co Ltd, Kim 1992 disclosed relevant antibodies and mentioned possible therapeutic potential, but did not disclose the claimed therapeutic effect or give clear and unmistakable directions to use the antibodies in therapy. The claims therefore remained novel.
4. Obviousness. The invention was the therapeutic use, not merely the possibility that the product might work. The structured approach in Pozzoli v BDMO was applied. An obvious-to-try case required a fair expectation of success in the claimed use, not merely a motive to begin a research programme or perform an experiment. Kim 1992 did not make anti-VEGF therapy, or the proposed research route, obvious.
5. Sufficiency. Under s 72(1)(c), the patent disclosed a principle of general application: successful VEGF blockade in tumour models supported a reasonable prediction that the strategy would work in at least some other angiogenic diseases. The claims were not insufficient merely because they covered further refinements, including VEGF Trap Eye, or because clinical trials were not disclosed. The evidence did not establish undue burden, ambiguity, or ineffectiveness of the claimed antagonists in the challenged diseases.
6. The patent was not invalid on any pleaded ground and was infringed by VEGF Trap Eye.