Home > Insights > Warner-Lambert Company LLC v Generics (UK) Ltd t/a Mylan and Actavis Group PTC – Part II
23 April, 2019

The Test for Infringement of a Patent for Manufacturing for a Limited Use


On 14th November 2018 the UK Supreme Court (UKSC) handed down its judgment in the case of Warner-Lambert Company LLC v Generics (UK) Ltd and Actavis Group PTC.

The case concerned a drug called pregabalin, which is an analogue of gamma aminobutyric acid (GABA), a neurotransmitter. Pregabalin was developed by Pfizer/Warner-Lambert and is authorised for treatment of epilepsy, general anxiety disorder (GAD) and neuropathic pain. It is sold under the brand name Lyrica. The European patent for pregabalin expired in May 2013 and its data exclusivity in July 2014. This cleared the way for generic entry into the market for use in treating epilepsy and GAD as these uses were not protected by patents. However, Warner-Lambert did still hold a European patent, EP-B-0934061 which included inter alia claims as follows:

Claim 1

Use of (s)-3-(aminomethyl)-5-methylhexanoic acid (pregabalin) or a pharmaceutical salt thereof in the preparation of a pharmaceutical composition for treating pain.

Claim 3

Use according to claim 1 wherein the pain is neuropathic pain.

Claims for revocation of the patent were lodged by Generics (UK) Ltd and Actavis Group PTC in 2014. In February 2015 Actavis launched a generic pregabalin product called Lecaent under a label which referred to use for epilepsy and GAD but not neuropathic pain (a so-called skinny label). In advance of this launch, in December 2014, Warner-Lambert brought an action against Actavis for infringement.

Prior to consideration by the UKSC, there had been seven High Court Judgments and two from the Court of Appeal addressing interim injunctions, sufficiency, inventive step, direct infringement, indirect infringement, unjustified threats and the right to amend.

By the time the case came before the UKSC the issues had been narrowed down to:

1. The construction of the claims;
2. The sufficiency of disclosure of the specification;
3. Amendments and abuse of process; and
4. The test for infringement of a patent for manufacturing for a limited use.

The parties were heard at trial in February 2018 before Lords Mance, Sumption, Reed, Hodge and Briggs.

This report concerns item 4 above, that is, the test for infringement of a patent for manufacturing a limited use. Items 1 to 3 above are discussed in Part I.

Test for infringement of a patent for manufacturing for a limited use

During the course of these proceedings claims 1 and 3, alleged to be infringed, had been held invalid for insufficiency. Thus the issue of infringement was no longer live before the UKSC. However, given the formidable analytical problems that arise determining infringement of medical use claims and the established practise of generic providers to use the “skinny label” as a tool to avoid infringement, their Lordships provided some obiter remarks. It was made clear that these remarks related solely to claims constructed in the Swiss form, “Use of compound X in the manufacture of a medicament for treating disease Y”, and not the newer style of claim available following the introduction of EPC2000.

It had been common ground between the parties that Swiss form claims are purpose-limited process claims. Pregabalin would thus be a product obtained directly by means of that process and direct infringement would come to be considered under section 60(1)c of the UK Patents Act. According to the wording of that section liability is absolute, depending entirely whether the act in question falls within the claims and pays no intention to the alleged infringer’s state of mind. It was nevertheless the position of the parties in the proceedings that in the case of a Swiss claim where the manufacture is of a product “for” a particular use, the intention of the manufacturer must be taken into account. Both the lower courts accepted there was a mental element to be considered when determining infringement of a Swiss form claim but disagreed about the nature of that element. In the High Court, Arnold J found that the manufacturer’s intention must be subjective. The manufacturer must make the product with the intent to target the patent protected market. A finding of infringement would be avoided if the manufacturer had taken all steps available to them to prevent infringement occurring.

On Appeal Mr Justice Floyd took the position of Warner-Lambert that the manufacturer’s intention was objective and that manufacturers must be taken to intend the foreseeable consequences of their actions. There would be infringement if it was foreseeable to the manufacturer that a more than de minimis amount of pregabalin manufactured would be used for treatment of neuropathic pain. However, this position was qualified by a finding that the requisite mental element could be negatived if the manufacturer had taken all reasonable steps to prevent the downstream use of pregabalin for treating pain.

In the UKSC judgment their Lordships did not agree on a common position as to what
actions should constitute infringement of a Swiss claim. Lord Sumption rejected the adoption of an infringement test that involved a mental element. He stated that “a test for infringement which depended on intention, whether subjective or objective, would be contrary to principle and productive of arbitrary and absurd results.”

His reasoning was that the pharmacists and doctors were not in a position to know the intentions of the manufacturer. Nor would the manufacturer have any control over the actions of the doctors and pharmacists. This could lead to a situation where, for example, the manufacturer made pregabalin with the intention that some of it could be used for treating pain, such that all downstream dealings in pregabalin would be dealings in the direct product of a patented process, even if all the product was in fact only used for treatment of epilepsy. He considered the mere foreseeability test would lead to a similarly absurd outcome.

His preferred solution when dealing with a purpose-limited process claim was the “outward presentation” test. He considered that the badge of purpose of such a claim is the physical characteristics of the product as it emerges from the relevant process including its formulation and dosage, packaging and labelling and the patient information leaflet which will identify the medical conditions for which the drug is intended. In his opinion this would apply an objective test not dependent on determining the mental state of the manufacturer and satisfy public policy considerations of striking a fair balance between the public interest in allowing the patentee to exploit his monopoly and in the free use of the invention for therapeutic uses which no longer have patent protection.

The position of Lord Sumption, in effect, means that a skinny label applied by a generic supplier would be enough to avoid infringement. Whether this really provides fair protection for the patentee is open to doubt because the patent holder will never be able to claim any compensation for the inevitable infringements which will take place where a generic product is available for other non-patented uses. Indeed, this potential unfairness led Lord Briggs and Lord Reed, in particular, to expressly take a different position to Lord Sumption.

Lord Briggs acknowledged the problem identified by Lord Sumption that if the manufacturer has no intention for the product to be used for a patent protected indication then dealers and pharmacists downstream of the manufacturer have no liability for infringement whatever their own intentions as to how the drug is to be used. By contrast, if the manufacturer does have such intention, then downstream users do not escape liability even where none of the drug is prescribed for the patented use. Nevertheless, he considered that in the Swiss claim, making something “for” a particular use must point to something in the mind of the manufacturer and could not agree with Lord Sumption about abandonment of the mental element. He rejected the mere foreseeability test put forward by Warner-Lambert but accepted that subjective intention of the manufacturer would have to be established. In this context he did not consider that the mere outward presentation of the product could be the only evidence of that intention. It was possible that the outward presentation could be a charade and that the manufacturer could be targeting the patent protected market by other means. Thus, other sorts of evidence could be advanced to show subjective intention. Accepting that this compromise was not ideal, as it falls short of providing complete protection to patentees of their monopoly, he considered it struck the fairest balance possible between the rights of the patent holder and the generic manufacturer in terms of public policy.

Lord Hodge also rejected Lord Sumption’s position and agreed that Lord Briggs’s approach provided a fairer balance of policy objectives.

Because the remarks of their Lordships in this case are obiter and there was no consensus, the principles to be applied in determining direct infringement of a Swiss form claim are not yet conclusively established in the UK. We must await a similar action in future where the relevant claim is held valid so that a real-world consideration of infringement is carried out.

Finally, it must be mentioned that Warner-Lambert had also brought a case against Actavis for indirect infringement under Section 60(2). This section does require a mental element in that a person indirectly infringes when they “know or it is obvious to a reasonable person in the circumstances” that what is supplied is suitable for and intended to put the invention into effect. It was unanimously agreed by their Lordships, following the findings of Arnold J that Actavis did not infringe under this section. The pregabalin product was manufactured on their behalf by a Bulgarian manufacturer who imported and distributed the product in the UK. The reason for the finding of non-infringement was that for a purpose-limited process claim, the invention protected is the manufacture of the drug for a designated use and not the subsequent use of the product for treating patients. Thus, indirect infringement could only arise by steps taken upstream of the manufacturing step and could not extend to any steps taken by the pharmacist.

While this case overall provides more certainty of the position to be adopted on the infringement of Swiss claims under section 60(2) than under section 60(1), opinion is often expressed that this is an incorrect way to construe a Swiss claim as the novelty and hence the invention resides in the purpose; the inclusion of the manufacturing step is a legal fiction to avoid the prohibition of claims to methods of medical treatment. It is to be expected however, that a different result under section 60(2) is likely to have been reached had the claim been of the new medical use style introduced by EPC 2000, where a manufacturing step does not appear.