In July of this year the Court of Appeal handed down its decision in Hospira v Genentech. While some interested parties may be disappointed that the product-by-process issues discussed in the first instance decision were not discussed further, the decision is of interest regarding the application of the question of obviousness in the courts of England and Wales.

Hospira v Genentech is an appeal from the decision of Birss J, dated 21 November 2014, regarding the revocation of two patents (European (UK) patent Nos. 1 516 628 and 2 275 119) covering pharmaceutical formulations of the monoclonal antibody trastuzumab in the breast cancer drug Herceptin. In the first instance decision Birss J held both patents invalid on the grounds of inventive step and added matter. Specifically, Birss J found that it was obvious to screen a particular selection of possible drug formulations to determine their relative stability.

Genentech appealed against the first instance decision, arguing that it was not obvious to try the particular formulations and even if it were, the person skilled in the art would have no expectation that the formulation recited in the claims would be stable relative to the possible candidates, therefore the person skilled in the art would not have the requisite expectation of success needed to establish obviousness.

In the Court of Appeal decision, Floyd LJ summarised the law of obviousness. In particular he cited Kitchin J in Generics v Lundbeck regarding the multifactorial nature of the question of obviousness and Lewison LJ in Medimmune Ltd v Novartis noting that “obvious to try” is only one approach to answering said question.

Floyd LJ also re-affirmed the standard approach of the appellate courts concerning appeals on the facts and that a first instance decision is not open to an independent evaluation by the Court of Appeal unless the judge has made an error of principle. In the present case, because the Court of Appeal rejected the grounds of appeal on the issue of obviousness, the remaining issues were not considered and the appeal was dismissed.

In dismissing Genentech’s appeal, Floyd LJ considered the could/would approach and provided a general conclusion that it is not necessary in every case

“for the court to conclude that the skilled person acting only on the basis of the prior art and his common general knowledge would arrive without invention at the precise combination claimed”.

He stated that, since the screening methods and excipients were common general knowledge and the tests were routine, it was clear that the combination could have been made by the person skilled in the art. Accordingly, it was necessary to ask

“whether this is the type of case where it is necessary to go further and ask whether the skilled person would necessarily have made the precise combination claimed”

On this question Floyd LJ went on to state:

“In an empirical field it will be seldom be possible to predict in advance that any individual experiment will work. In many cases, the fact that a routine screening exercise could be carried out will be inadequate to establish obviousness. Nevertheless, on the facts of an individual case such as the present, the team may have a reasonable degree of confidence that a series of experiments will produce some which will work. To impose a requirement that the skilled team must be able to predict in advance which would be the successful combinations is wholly unrealistic. It would lead to the grant of patents for a whole variety of combinations which in fact involved no inventive effort.”

In the case in question he found it was not necessary to show that the specific combination would be obvious. Instead, it was enough to show that embarking on a screening process, which encompassed the claimed formulation, was obvious. Richards LJ and Kitchin LJ both agreed.

In summary we find that the court of appeal has clarified that, regarding obviousness, the question to be answered is the statutory one and, while the rules and approaches found in the case law may be helpful, none fit all cases. On this point Floyd LJ noted that he was reminded of the often quoted passage from Savage v Harris & Sons (1896):

“Cases, so far as regards the law, are most useful, but when they are applied to particular facts, they, as a rule, are of little service. Each case depends on its own particular facts and the facts of almost every case differ.”