Medimmune Ltd v Novartis Pharmaceuticals UK Ltd & Ors

Patent obviousness requires an assessment of whether the claimed product or process was obvious to the skilled but unimaginative addressee at the priority date. All relevant circumstances must be evaluated together. A fair expectation of success and the anticipated duration of experiments are considerations within that assessment, rather than successive legal conditions. A publicly disclosed proposal may render its implementation obvious where known techniques suffice and the skilled team would reasonably expect success. Practical use is relevant to common general knowledge, but its absence does not necessarily exclude a concept. Appellate courts should exercise caution before disturbing a trial judge’s evaluation of obviousness.

On priority, the court additionally concluded that the earlier application must disclose the claimed subject matter directly and unambiguously, with an enabling disclosure read as a whole. An obvious development of that disclosure is insufficient.

MedImmune Limited and the Medical Research Council jointly owned patents concerning antibody phage display, a technique for selecting antibody fragments with desired binding properties. MedImmune alleged that Novartis Pharmaceuticals UK Limited infringed the patents by selling ranibizumab, a treatment for wet age-related macular degeneration. The Medical Research Council was joined to be bound by the result and took no active part.

Arnold J held both patents invalid for obviousness and lack of priority. He also held that their claims did not cover the manufacturing process. MedImmune pursued its appeal only concerning European Patent (UK) No 2 055 777. In related proceedings, Novartis obtained a declaration that a supplementary protection certificate based on that patent was invalid. The judge additionally found the certificate invalid even on the assumption that his earlier findings were wrong.

The Court of Appeal heard full argument on obviousness and priority. The central questions were whether a public presentation proposing antibody phage display made the claimed method obvious, and whether the priority application disclosed subsequent modification of selected binding molecules without further phage-display selection.

Both appeals dismissed. Kitchin LJ’s reasons were accepted by Lewison and Moore-Bick LJJ. Moore-Bick LJ also endorsed Lewison LJ’s additional observations on obviousness.

1. The skilled addressee was properly identified as a research team interested in antibody engineering. The court should consider the problem addressed, the relevant art and the combined skills of actual research teams. The invention’s possible wider application did not alter that conclusion. A concept could form part of common general knowledge despite limited practical use. The evidence supported the finding that the basic concept of phage display was common general knowledge ([72]–[82]).

2. Under sections 1(1) and 3 of the Patents Act 1977, the ultimate question was whether making the claimed product or carrying out the claimed process was obvious. The structured approach in Pozzoli v BDMO SA was useful but optional. The assessment concerned the claim, rather than a paraphrase of the description. Whether a route was obvious to try depended on all relevant circumstances, including the expectation of success, available research routes, effort and experimental demands. Lewison LJ emphasised that a fair prospect of success and a reasonable timescale were interacting considerations, rather than separate conditions ([84]–[95]; [177]–[183]).

3. The public presentation went materially beyond the earlier paper. It expressly proposed antibody phage display, announced an intended experiment and addressed possible difficulties and solutions. Its positive message rested on scientific work and analysis. Implementation required ordinary techniques already disclosed. The trial judge was entitled to find that the skilled team would reasonably expect success within a reasonable time. Neither the description of the wider research project as speculative nor its funding timescale required a different conclusion. The inventor’s subsequent experiment demonstrated the principle despite disappointing enrichment. No error of principle justified appellate interference ([125]–[148]).

4. Although priority was unnecessary to dispose of the appeals, the court expressed its conclusions after full argument. Section 5(2) (a), interpreted consistently with Article 87(1) of the European Patent Convention, required direct and unambiguous, enabling disclosure of the claimed subject matter in the earlier application as a whole. An obvious development was insufficient. The claim covered derivatives produced after phage-display selection without further selection. The priority document taught modification followed by phage-display selection, including repeated cycles. It did not disclose using modified derivatives without that further selection. Claim 1 therefore lacked priority, providing a further reason for invalidity ([149]–[175]).

Obviousness disposed of both appeals. By agreement, the court heard no further argument on infringement, insufficiency or the additional grounds concerning the supplementary protection certificate ([5]).

• Court of Appeal (Civil Division): [2012] EWCA Civ 1234 . Dismissed both appeals. Upheld the finding of obviousness and additionally agreed that claim 1 lacked priority. The remaining issues were not pursued after obviousness was found dispositive.
• High Court, Chancery Division (Patents Court): Arnold J held both patents invalid for obviousness and lack of priority, and held that their claims did not cover the manufacturing process. In related proceedings, he declared the supplementary protection certificate invalid and identified an additional ground of invalidity. The citations of those judgments are not stated in the judgment.