Alcon Research LLC & Anor. v Pharmathen SA & Anor.

In a patent obviousness appeal, the assessment is multifactorial and appellate intervention requires an error of law or principle. Where the skilled addressee is a team, the law requires neither a permanent leader nor the absence of leadership. Each member performs their own role, and the team’s structure is fact-specific.

Obviousness depends on the direction of the prior art, motivation to pursue a proposed route and expectation of success. A research project that could be undertaken as a gamble is not necessarily obvious. For a second medical-use patent, plausibility must be assessed against the claimed therapeutic effect. An insufficiency squeeze fails if the premise on which the obviousness argument depends has not arisen.

Alcon, the proprietor and exclusive licensee of a patent and supplementary protection certificate concerning travoprost, obtained an interim injunction when Pharmathen and Aspire prepared to market generic eye drops. By trial, the patent and SPC had expired, but Alcon’s potential liability under its cross-undertaking remained.

Meade J rejected challenges based on lack of novelty, obviousness and insufficiency: [2021] EWHC 1026 (Pat). Aspire appealed on obviousness and insufficiency. The central issues were whether the skilled team would have been led by the pharmacologist, whether the prior art made it obvious to try fluprostenol isopropyl ester, and whether the patent plausibly disclosed the claimed suitability for treating glaucoma.

1. Appeal dismissed. Obviousness is a multifactorial evaluation, and the Court of Appeal will not interfere absent an error of law or principle. The judge’s failure expressly to record that the pharmacologist led the skilled team was an error, but it did not undermine the assessment.
2. Where the skilled addressee is a team with differing skills, each member plays their own part. The law neither requires one member to be a permanent head nor prohibits one member from taking the lead. The relationship between members is fact-specific. On the evidence, the pharmacologist led because the medicinal chemist lacked specialist knowledge of glaucoma and prostaglandins. That did not remove the medicinal chemist’s role in deciding the appropriate course.
3. The judge was entitled to find that the obvious route from Stjernschantz was to investigate further prostaglandin analogues through structural variations rationally derived from its structure-activity work. The prior art did not mention fluprostenol. Its common general knowledge status was principally as an analytical tool, and its veterinary use was remote from glaucoma treatment. The skilled team would not without invention have turned to it, and there was no positive expectation of success in achieving efficacy with reduced side effects. A low-resource research gamble would not itself make the invention obvious.
4. For a second medical-use patent, the specification must plausibly disclose the claimed therapeutic effect. The criterion stated in Warner-Lambert Co LLC v Generics (UK) Ltd [2018] UKSC 56 was accepted. The insufficiency argument was pleaded only as a squeeze against obviousness. Since obviousness had not been rejected on the basis that fluprostenol isopropyl ester caused the relevant side effects, the premise of the squeeze did not arise.
5. The technical contribution of a patent is an objective question for the court and is not determined by the patentee’s pleaded case. The judge’s contrary reasoning was legally erroneous, but the insufficiency challenge nevertheless failed on the pleaded basis.

• Court of Appeal (Civil Division): Aspire’s appeal from the Patents Court was dismissed.
• High Court of Justice, Patents Court: Meade J rejected the challenges to validity on novelty, obviousness and insufficiency in [2021] EWHC 1026 (Pat).