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Validity and infringement

Posted on 5 March 2019

Validity and infringement

Supreme Court upholds insufficiency of pregabalin second medical use patent

In a much anticipated judgment, the Supreme Court issued its decision in Warner-Lambert v Mylan & Actavis in November 2018, focusing on how concepts of patent sufficiency and plausibility, and infringement, should be assessed in relation to second medical use patents. The decision, that the second medical use patent for Lyrica is invalid, was of extreme importance to the parties – Lyrica is one of the Pfizer Group’s most successful drugs in the UK and a number of pharmaceutical companies had launched generic products. However, it also has much broader significance in terms of the potential implications for clinical and prescribing practices, with the Secretary of State for Health making submissions, alongside no fewer than nine other interveners from a range of interested bodies.

The split in the Lordships’ views on a number of central issues clearly demonstrates, as Lord Sumption put it, that “patent protection for second use medical patents is … difficult to accommodate within the traditional scheme of patent law”. However, the majority view in relation to plausibility has the potential for imposing a higher hurdle in relation to sufficiency of pharmaceutical patents generally. Meanwhile, the obiter discussion on the proper approach to infringement of second medical use patents, with references to compromises and ‘least imperfect’ solutions, suggests plenty of scope for further debate, including in relation to infringement of other purpose-limited claims.

Was the disclosure in the specification sufficient?

This was a split decision. The majority (Lords Sumption, Reed, and Briggs) considered that the disclosure in the specification was not sufficient to support the claims in relation to neuropathic pain, whether peripheral or central (it did support the claims so far as they claimed inflammatory pain). Lord Sumption described plausibility as just one element in the test of sufficiency: “Plausibility is not a distinct condition of validity with a life of its own, but a standard against which that must be demonstrated. Its adoption is a mitigation of the principle in favour of patentability … The test is relatively undemanding. But it cannot be deprived of all meaning or reduced … to little more than a test of good faith”. In particular, he identified a number of principles that will influence the plausibility assessment.

Lords Hodge and Mance, in the minority, preferred a lower standard of plausibility which would not require the patentee to demonstrate within its patent a prima facie case of therapeutic efficiency. Lord Mance suggested that Lord Sumption’s analysis imposed “too high a threshold, and imposes a burden on a patentee” unsupported and unjustified by the EPO case law.


Given the findings on sufficiency, the Court’s comments in relation to infringement were obiter. The Court agreed that Actavis’ Lecaent product would not infringe (directly or indirectly), but for differing reasons in relation to direct infringement. They all rejected the Court of Appeal’s qualified foreseeability approach, but Lords Sumption and Reed adopted a position based on neither of the parties’ positions, rejecting a role for intention entirely. Instead, the sole criterion is an (objective) ‘outward presentation’ test. Under this test, the assessment is whether the product, as it emerged from the manufacturing process, including its packaging and labelling and patient information leaflet, was presented as suitable for the uses which enjoy patent protection. On the facts, Lecaent was sold with patient information leaflets stating it was for the treatment of seizure disorders and GAD (but not pain).

Lord Mance agreed that the objective appearance and characteristics of the product as it is prepared, presented and put on the market was relevant. However, he left open the possibility that there may be rare cases where the context makes it obvious that these are not to be taken at face value, or circumstances where the generic manufacturer should positively exclude use for the patent-protected purpose.

Lords Hodge and Briggs, however, thought that the test is whether the alleged infringer subjectively intended to target the patent-protected market, albeit they also recognised that this ‘so-called subjective test’ remained a compromise.

Court of Appeal considers doctrine of equivalents in ice rink case

12 months on since the Supreme Court’s ground-breaking decision in Actavis v Eli Lilly confirming a role for a doctrine of equivalents when assessing the scope of protection of a patent, the Court of Appeal had its first opportunity to consider the application of the test in Icescape v Ice-World, a case concerning a patent relating to mobile ice rinks. Whilst the Court of Appeal decided that the Patent was invalid as it was not entitled to its claimed priority date, it also said that, if the Patent were valid, Icescape’s ice rink would have infringed under the doctrine of equivalents applying the Actavis v Lilly test. 

The case is interesting for a number of reasons. It is the first IP case to have reached the Court of Appeal having been heard under the streamlined ‘Shorter Trial Scheme’ and demonstrates how a patentee can succeed under the doctrine of equivalents, even if not under a purposive construction. The Court of Appeal said that the trial judge had been correct to conclude that Icescape’s ice rink did not infringe the Patent on a purposive interpretation (albeit this was not an easy question), but it did satisfy the aims of the Patent and did so in substantially the same way, and this would have been obvious to a person skilled in the art. 

As Lord Justice Floyd commented: “it is now clear from the Supreme Court’s decision in Actavis that purposive construction forms but the first stage in the determination of the scope of protection conferred by the claims … there is a second non-interpretative exercise which allows the patentee a degree of protection outside the normal, purposive meaning of the claims where the variant from the claim achieves substantially the same effect in substantially the same way”. The claims, however, remain important and are the starting point for analysing variants. Further, he noted, there are still issues arising out of the Actavis v Lilly decision that remain to be resolved, including the approach to the scope of protection when considering validity as opposed to infringement, and the approach to inventive variants.

Already in 2019, we are seeing a number of cases considering the doctrine of equivalents (including Regen Lab v Estar and Technetix v Teleste); in the latter case, the Court also considered the possibility of a ‘Formstein’ defence which will allow an equivalent which falls within the scope of the claim, but which would have lacked novelty or inventive step over the prior art at the priority date, to provide a defence to infringement. This is a development to watch further.

Patents Court awards Arrow declaration

In December 2018, Arnold J gave his judgment in Glaxo v Vectura, a dispute concerning GSK’s Ellipta inhaler products for asthma and chronic obstructive pulmonary disease. Aside from finding non-infringement, the key (and rare) finding was that all of Vectura’s patents were invalid for insufficiency on the grounds of ambiguity. This was because they did not enable the skilled person to determine whether a process or product fell within the claims without undue effort. 

In addition, the Court granted GSK an Arrow declaration, in the light of its concern that Vectura may seek to rely on other patents against it, including a pending application which may be split into divisionals. We discussed the Court’s jurisdiction to make Arrow declarations in our review of the Humira litigation.

The Court agreed that GSK’s process, and therefore the products obtained as a direct result, were objectively obvious in the light of the prior art. The declaration would serve a useful purpose, in the circumstances of the case “because it would formalise and emphasise the conclusion” reached in relation to the obviousness of GSK’s process and products in relation to the prior art. 

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