Supreme Court hands down judgment on second medical use patents

14/11/18

An important aspect of modern pharmaceutical research is the discovery of new medical uses for known molecules. Obtaining patent protection is often important in order to secure a return on the investment that has been made in researching and trialling the new medical application.

Patents for so-called second medical uses are, however, very difficult to accommodate within the usual scheme of patent law. One of these difficulties is that the molecule and process by which it is manufactured are previously known with the result that there is no novelty in the invention. Furthermore, the Patents Act contains a public policy exclusion which prevents the grant of patents for methods of treatment of the human or animal body.

In the 1980s the Swiss Federal Intellectual Property office issued a statement that it would grant patents for second medical uses in the form “the use of a compound X in the manufacture of a medicament for the treatment of indication Y”. These became known as Swiss-form claims and were approved by the Enlarged Board of Appeal of the European Patent Office with the result that claims in this form were granted throughout the member states of the European Patent Convention including the UK.

Supreme Courts throughout Europe have grappled over the last few years with exactly how to interpret claims in the Swiss-form and the circumstances in which they might be infringed. A particular problem arises over whether intention must be demonstrated and by whom. Earlier today the UK Supreme Court handed down judgment in Warner Lambert v Generics [2018] UKSC 56 which concerned the drug pregabalin marketed under the Lyrica brand. Pregabalin is used for the treatment of siezures including epilepsy and Warner Lambert obtained a second medical use patent in respect of pregabalin for treating pain.

The issues in the appeal included (1) the construction of the claims in the Swiss form, (2) the sufficiency of the disclosure in the specification of the patent, (3) whether it was permissible to amend the patent following trial and whether that constituted an abuse of process, and (4) the test for infringement of a Swiss form claim. The Court (Lords Mance, Sumption, Reed, Hodge and Briggs) refused Warner Lambert’s appeal but disagreed on a number of points. In relation to infringement the Court carried out a wide ranging comparative analysis of German and other overseas case law and the majority (Lords Sumption, Reed, Hodge and Briggs) held that if the claims had been valid they would not have been infringed. Lords Sumption and Reed considered that the intention of the alleged infringer is irrelevant and the sole criterion of infringement is whether the product as it emerges from the manufacturing process is presented as suitable for the uses which enjoy patent protection. Lord Mance agreed that the test depends on the objective characteristics of the manufactured product but leaves open the possibility that in rare cases the context may make it obvious that the presentation of the product is not to be taken at face value. Lords Hodge and Briggs preferred the view of Arnold J below that the test should be whether the alleged infringer subjectively intended to target the patent-protected market. Arnold J found at trial that that they did not.

The Supreme Court judgment is here.

Press coverage by Reuters is here.