Hospira UK Ltd v Genentech Inc

Obviousness requires a fact-sensitive, multi-factorial assessment. Relevant matters include the motivation to address the problem, the available research routes, the effort required and the skilled team’s fair expectation of success.

An obvious to try inquiry is only one consideration. In an empirical field, a routine screening programme can render a formulation obvious where the skilled team would reasonably expect some promising combinations, even though it could not predict in advance which precise combination would succeed. The law does not require commercial certainty or advance prediction of the successful combination. An appellate court will not revisit that evaluation unless the trial judge made an error of principle.

Hospira sought revocation of two European patents (UK) owned by Genentech concerning a freeze-dried formulation of trastuzumab. The formulation used trehalose as lyoprotectant, histidine as buffer and polysorbate 20 as surfactant.

Birss J held the patents invalid for lack of inventive step and added matter: [2014] EWHC 3857 (Pat). He found that, starting from Carter’s disclosure of trastuzumab in liquid formulation, a skilled team would be motivated to develop a lyophilised version and would reach the claimed formulation through routine screening of common general knowledge excipients.

Genentech appealed, principally contending that the judge had confused what the skilled team could do with what it would do, and had found obviousness without a fair expectation of success.

1. Appeal dismissed. Floyd LJ, with whom David Richards and Kitchin LJJ agreed, held that Birss J made no error of principle in finding the claimed formulation obvious over Carter. The finding of lack of inventive step therefore stood; the remaining issues did not arise.

2. Obviousness is assessed by reference to all the circumstances. Relevant factors include the motivation to pursue the project, the possible research avenues, the work involved and the reasonable or fair expectation of success. An obvious to try inquiry is not a substitute statutory test, although it may be relevant when combined with a fair prospect of success.

3. The judge was entitled to find sufficient motivation. Carter disclosed trastuzumab in phase II trials for breast cancer. In light of the recognised importance of the HER2 target, that disclosure would interest the skilled clinical and formulation team. The judge was also entitled to infer that a liquid formulation could not be adequately stabilised and that development of a lyophilised formulation would be pursued.

4. The evidence supported an ex ante fair expectation that routine screening would produce promising lyophilised formulations. The relevant excipient classes and the particular candidates were part of common general knowledge, were used for known purposes, and there was no evidence that trastuzumab presented special formulation problems.

5. The law did not require the skilled team to predict which individual combination would succeed or to be bound to select the precise claimed combination. In an empirical field, a team may reasonably expect that routine experiments will produce some successful combinations. The inability to identify them in advance does not itself create inventive step. Conversely, a screening exercise undertaken merely in the hope that something might turn up may be insufficient on different facts.

6. The Court of Appeal could not independently re-evaluate the judge’s interdependent factual assessments absent an error of principle. None was shown.

• Court of Appeal (Civil Division): dismissed Genentech’s appeal and upheld the finding that the patents lacked inventive step: [2016] EWCA Civ 780.
• High Court, Chancery Division, Patents Court: Birss J held both patents invalid for lack of inventive step and added matter: [2014] EWHC 3857 (Pat).