Regeneron Pharmaceuticals Inc v Bayer Pharma AG

A medical-use claim requires the claimed therapeutic effect, although treatment need neither cure the disease nor address every aspect of it. For novelty, prior art which merely predicts therapeutic potential does not disclose therapeutic efficacy or give clear and unmistakable directions to perform the invention.

Obviousness depends on all the circumstances. Where an obvious-to-try analysis is relevant, the court may distinguish a reasonable or fair expectation of success from a mere hope. A broad claim is sufficiently enabled where the patent makes it plausible that a disclosed principle will work substantially throughout its scope without undue effort. It may encompass later inventive improvements which embody the patent’s technical contribution.

Regeneron Pharmaceuticals Inc and Bayer Pharma AG sought revocation of Genentech Inc’s patent for using human vascular endothelial growth factor antagonists to treat non-neoplastic diseases characterised by excessive neovascularisation. They also sought a declaration that VEGF-Trap, intended to treat neovascular age-related macular degeneration, did not infringe. Genentech counterclaimed for infringement.

Floyd J rejected attacks based on lack of novelty, obviousness and insufficiency. He held that the claims encompassed VEGF-Trap. The appellants challenged the construction of the claims, infringement, novelty over Kim 1992, inventive step and sufficiency, including whether the patent plausibly and adequately enabled its broad therapeutic claims.

1. Appeals dismissed. The claims required a therapeutic effect. The medicament had to improve the patient’s condition by treating the angiogenic component of the disease. It did not have to cure the disease or treat aspects independent of angiogenesis. The phrase “isolated hVEGF receptor”, read purposively in the context of the specification, included variants and fragments which retained the ability to bind VEGF and inhibit its biological activity. VEGF-Trap satisfied that description and infringed.
2. Kim 1992 did not anticipate the claims. For a medical-use claim, attainment of the therapeutic effect is a functional technical feature. Kim 1992 disclosed antibodies and predicted that they might have therapeutic potential, but neither disclosed their use in therapy nor gave clear and unmistakable directions to achieve the claimed therapeutic effect. A prediction of possible therapeutic effect was not disclosure that the effect existed.
3. The invention was not obvious. Whether an avenue was obvious to try and whether there was a fair expectation of success were relevant on the way the appellants advanced their case. Although the skilled team had strong motivation to investigate anti-angiogenic therapy and might logically have performed a mouse xenograft test, VEGF was only one of many possible factors. The accepted concern about biological redundancy meant that the team lacked a reasonable or fair expectation that targeting VEGF would succeed therapeutically.
4. The claims were sufficiently disclosed. A broad claim is permissible where the patent discloses a principle of general application and it is reasonable to predict that the invention will work substantially throughout its scope. The patent showed that VEGF blockade could prevent pathological angiogenesis in tumour models. Since neovascular diseases shared angiogenesis as a common thread, it was reasonable to predict efficacy against the angiogenic component of non-neoplastic neovascular diseases. The evidence did not establish material inoperative embodiments or an undue burden in identifying effective antagonists and diseases.
5. A therapeutic patent need not prove regulatory approval, suitability for every patient or successful treatment of every aspect of a disease. Nor was it insufficient because its claims encompassed VEGF-Trap, a later inventive improvement. Chimeric receptor variants were contemplated and could be produced using standard techniques; VEGF-Trap embodied the patent’s technical contribution despite requiring additional ingenuity.

Moses LJ and Longmore LJ agreed with Kitchin LJ.

1. Court of Appeal (Civil Division): The court dismissed both appeals and affirmed the findings of validity and infringement in [2012] EWHC 657 (Pat).
2. High Court, Chancery Division (Patents Court): Floyd J rejected challenges based on lack of novelty, obviousness and insufficiency, and held that the patent claims encompassed VEGF-Trap.