In the English Patents Court, Mr Justice Arnold has ruled that key (broad) claims of Warner-Lambert's "second medical use" patent to pregabalin for the treatment of pain (Swiss form claims) are invalid for insufficiency, and that the patent is not infringed by Actavis' activities involving its generic pregabalin medicine: "Lecaent". Further, Warner-Lambert and parent company Pfizer are liable for threats and Actavis is entitled to declaratory relief.

Arnold J had already issued four interim judgments in this well-publicised dispute, in addition to case management orders, and the Court of Appeal has issued one decision. Our previous commentary is available here:

Arnold J's latest decision, handed down on 10 September 2015, is the first in the substantive dispute between the parties. Weighing in at over 80,000 words (727 paragraphs) it is a standard Arnoldian tour de force, although it could be said the judgment waves a red flag to the Court of Appeal.

In this alert we pick out some of the more noteworthy points from Arnold J's judgment, discussing their context and implications. We also provide commentary on the judge's approach and findings. It is to be expected that the Court of Appeal will have more to say on another day.

Background

Warner-Lambert Company LLC's (Warner-Lambert's) European Patent number EP(UK) 0 934 061 (the Patent) is a second medical use patent with claims in Swiss form directed to the use of pregabalin for treating pain, including the following claims:

Claim 1: "Use of [pregabalin] or a pharmaceutically acceptable salt thereof for the preparation of a pharmaceutical composition for treating pain"

Claim 3: "Use according to claim 1 wherein the pain is neuropathic pain".

Warner-Lambert markets pregabalin under the trademark Lyrica for the treatment of epilepsy, generalised anxiety disorder (GAD) and neuropathic pain, through group company Pfizer Ltd. Arnold J referred to Warner-Lambert and Pfizer, collectively, as "Pfizer".

In 2014, the validity of the Patent was challenged by Generics UK Ltd (trading as 'Mylan') and then by Actavis PTC EHF (Actavis). The actions were ordered to be heard together and Warner-Lambert counterclaimed against Actavis for infringement. Arnold J's 10 September 2015 decision, being a decision in the combined revocation (and infringement) actions, is titled according to the senior claim: Generics (UK) Ltd (t/a Mylan) v Warner-Lambert Company LLC [2015] EWHC 2548 (Pat).

Other parties to the litigation are Caduceus Pharma Ltd (which holds a marketing authorisation for Actavis' 'Lecaent' pregabalin medicine), Pfizer Ltd and the Secretary of State for Health (as an intervener). Generics and Actavis presented their cases together.

Construction

Before considering the challenges of obviousness and insufficiency, Arnold J construed the patent claims and made the following noteworthy rulings:

  • The word "treating" in the claim language was a functional technical feature of the claim i.e. the actual attaining of the therapeutic benefit was a technical feature of the claimed invention. Arnold J ruled that the criterion for establishing such efficacy was a positive result in one of the three animal models used in the patent (not, as Warner-Lambert contended, the results of phase II clinical trials).
  • Claim 1 required the use of pregabalin be for treating "pain", which Arnold J ruled embraced all types of pain. The judge disagreed with Warner-Lambert's contention that the skilled team would interpret it as restricted to "types of pain characterised by hyperalgesia and/or allodynia and having a central sensitisation component", saying there was, for example, no mention of "central sensitisation" anywhere in the patent.
  • Claim 3 was its use for treating "neuropathic pain", which Arnold J ruled encompassed both central and peripheral types of neuropathic pain and not (as Warner-Lambert contended that the skilled person would understand it) limited to peripheral neuropathic pain. Arnold J reasoned that the term appeared to be used in the patent quite generally, with no reference to "peripheral neuropathic pain", nor any indication that central neuropathic pain was not intended to be included.

Arnold J. made further rulings about the mental element imputed into the language of a Swiss form claim by the word "for", which we discuss in the context of infringement, below.

Inventive step

The judge made the following observation on the law regarding inventive step:

"292. Counsel for Warner-Lambert submitted that Mylan and Actavis must show that it would have been obvious to the skilled team that pregabalin would be effective to treat pain, but he nevertheless accepted that it was relevant to consider whether the skilled team would have a fair expectation of success if it were to try pregabalin for the treatment of pain. In my judgment this is the correct test for the reasons I gave in Hospira UK Ltd v Genentech Inc [2015] EWHC 1796 (Pat) at [108]-[115]."

As noted above, in the context of construing the claim language ("treating"), the judge ruled that the criterion for determining the "actual attaining of clinical benefit" was a positive result in one of the three animal models used in the patent. Following on from this, he considered Mylan and Actavis' challenge of obviousness by asking whether it would have been obvious to the skilled person to test pregabalin in one of the three animal models used in the patent with a fair expectation of success.

The judge observed that Mylan and Actavis' case suffered from the "basic difficulty" that none of the prior art relied upon disclosed both pregabalin (a derivative of the natural inhibitory neurotransmitter γ-aminobutyric acid (GABA)) and use for the treatment of neuropathic pain. Their case relied upon combinations of prior art documents being read by the skilled person together.

For example, one combination was based upon: (i) "Mellick", which provided only anecdotal evidence that gabapentin (another derivative of GABA) was efficacious for the treatment of pain, in combination with (ii) "Taylor II", which disclosed that gabapentin was an effective anticonvulsant and that pregabalin had structural similarity with it. For each combination, the judge considered that Mylan and Actavis had asserted a step-by-step argument to suggest that the skilled team would reach the invention, which he found was based on hindsight. The invention was not obvious.

Insufficiency

Mylan and Actavis challenged the sufficiency of a number of the claims of the patent, including claims 1 and 3.

Arnold J referred to the Court of Appeal's approval, in Eli Lilly v Human Genome Sciences of Kitchin LJ's summary of the principles regarding sufficiency (of the 'classical' type), and to Kitchin LJ's (perhaps more pertinent) summary of the principles relating to the 'Biogen'/excessive claim scope type insufficiency, in Regeneron v Genentech. Of particular relevance to his assessment was Kitchin LJ's comment in Regeneron that:

"the assertion that the invention will work across the scope of the claim must be plausible or credible. The products and methods within the claim are then tied together by a unifying characteristic or a common principle".

When considering sufficiency, Arnold J. followed the Court of Appeal's guidance in Schlumberger v Electromagnetic Geoservices [2010] EWCA Civ 819 that the team has by that time read the patent. Following his finding on construction, the issue he considered was of plausibility in light of the animal models presented in the patent. As such, the neuroscientist would take the lead.

The judge noted that the specification of the patent did not claim that the data presented showed that pregabalin was effective in the treatment of neuropathic pain, although it did mention two models for neuropathic pain.

The judge found that it was common general knowledge that central sensitisation was thought to be involved in peripheral neuropathic pain and in inflammatory pain but that it was not thought to have a role in central neuropathic pain.

As regards the treatment of inflammatory pain, the specification stated that data presented in another test, the 'rat paw formalin test', showed that pregabalin was effective. The involvement of central sensitisation in peripheral neuropathic pain would have suggested to the skilled team that it was possible that a drug which was effective in inflammatory pain (as modelled by the rat formalin test) would also be effective in peripheral neuropathic pain. As such, the data contained in the specification, when read in light of the common general knowledge, "just" made it plausible that pregabalin would be effective to treat peripheral neuropathic pain.

However, for central neuropathic pain, in which central sensitisation was not thought to be involved, the claim that pregabalin would be effective was not plausible. A key finding on the common general knowledge in this context was that the rat paw formalin test was not considered predictive of efficacy for neuropathic pain. On this, Arnold J favoured the evidence given by Mylan and Actavis' neuroscientist, Professor Wood. He said that the views of Warner-Lambert's expert in this field, Professor Woolf, were "significantly influenced by post priority information or materials that were not part of the common general knowledge at the priority date". Some of the time, the judge thought Professor Woolf was subconsciously supporting Warner-Lambert's case, and suggested a reason for this might have been that Professor Woolf had previously participated in US proceedings.

Further, said Arnold J, even if there was, as Warner-Lambert asserted, sufficient data in the Patent to make it obvious to try pregabalin for neuropathic pain, that was not enough for sufficiency.

The consequence of this was that Arnold J concluded in favour of Mylan and Actavis on sufficiency. While he upheld the claims which focus on inflammatory pain, he revoked the key claims 1 and 3 (as well as some others) on this basis.

On the other hand, claims 10 (trigeminal neuralgia pain), 11 (post-herpetic neuralgia pain) and 12 (causalgia pain) were apparently accepted by Mylan and Actavis as falling within 'periperal' neuropathic pain. These claims were found to be valid.

It is perhaps noteworthy that Arnold J's conclusion that claim 3 (neuropathic pain) was invalid for insufficiency was reached despite the fact that there was no dispute that the invention could, in fact, be performed across the scope of the claim. The judge agreed with Mylan and Actavis that "later work does not justify a claim which was speculative when it was made".

Infringement

Construction - Arnold J's commentary on Floyd LJ's judgment

Arnold J stated that being in Swiss form, the claims of the patent were process claims. Citing Actavis v Merck [2008] EWCA Civ 444 and Floyd LJ's interim Court of Appeal judgment in this case Warner-Lambert v Actavis [2015] EWCA Civ 556, he said that the Court of Appeal had held that

"such claims are directed to the manufacturer of the medicament or pharmaceutical composition".

Arnold J. then turned to address the Court of Appeal's interim judgment in relation to infringement. He agreed with Mylan and Actavis that the Court of Appeal's commentary on the construction of the Swiss form claim in issue was obiter because his original decision to refuse interim relief was not overturned. (It is worth noting here that the Arnold J does not appear to have considered the nature (whether obiter or ratio) of the Court of Appeal's decision to overturn his decision to strike out Warner-Lambert's claim for indirect infringement pursuant to section 60(2). We return to this point below).

Arnold J expressed some disagreement with Floyd LJ's construction of the Swiss form claim in issue. For example, he said that Floyd LJ's construction apparently had the consequence

"that, if it was foreseeable to an unlicensed manufacturer of pregabalin that "some of his drug" (as Floyd LJ put it at [127], emphasis added) would be intentionally administered for the treatment of pain, then all of that manufacturer's acts of manufacture of pregabalin would be infringing acts even though it was foreseeable that the remainder of its pregabalin would be administered for the treatment of non-patented indications...further, all of the pregabalin would be infringing product, and thus anyone who subsequently dealt in it would also infringe on a strict liability basis".

Arnold J commented that he thought it was "reasonably clear" from Floyd LJ's judgment that he did not intend his interpretation to have this consequence. However, the only indication he could see as to how Floyd LJ thought it was to be avoided was in the discussion of the question of remedies.

Despite his "considerable doubts as to the correctness of Floyd LJ's interpretation", however, Arnold J said that he was not "entirely convinced" that it was wrong, and so he proposed to follow it.

Construction - Arnold J's application of Floyd LJ's commentary

Yet there remained dispute between the parties as to how Floyd LJ's judgment should be applied. On this Arnold J ruled as follows:

"634. ...First, counsel for Pfizer submitted that there was no real difference between Floyd LJ's interpretation of the word "for" and a pure test of foreseeability on the part of the manufacturer that its pregabalin would in fact be used for the treatment of pain. I do not accept this submission. Floyd LJ made it clear at [121] that intentional administration was at the heart of the invention, at [122] that the word "for" provided the link between the manufacture of pregabalin and the intentional use of the drug, at [127] that the word "for" required knowledge or foresight of the ultimate intentional use, at [128] that there were two mental states involved and at [129] that a manufacturer infringes when he knows or foresees that users will intentionally administer pregabalin for the treatment of pain. Thus the requirement of intention is central to his interpretation. It is plainly not a pure test of foreseeability. Furthermore, I agree with counsel for Actavis that a pure test of foreseeability would not be enough to confer novelty on the claim. It is the element of intention which ensures novelty."

On his assumption that intention was required as a part of the mental element of the claim (to which we return later), Arnold J then considered how and by whom that requirement could be fulfilled. His view was that:

  • the doctor prescribing pregabalin generically would not have the necessary intent because the doctor would not be intending the manufacturer's (i.e. Actavis') pregabalin to be administered for pain;
  • the pharmacist who dispenses any generic pregabalin in fulfilment of a generic prescription without reference to the indication would similarly not have the necessary intent, alone or in combination with the doctor;
  • however dispensation of the manufacturer's product in fulfilment of a generically written prescription on which the pain indication was specified would be enough;
  • the patient's intention is irrelevant.

With this very limited window of potential "intent" in mind (i.e. point 3 above), Arnold J then went on to assess whether, and if so when, the necessary mental element of the patent claims (had they been valid) had been reached by Actavis.

Direct infringement - was the necessary mental element met on the facts?

It was common ground between the parties that the date upon which the manufacturer's mental element must be satisfied was the date of manufacture.

Actavis accepted that when packaging its first batch of Lecaent for the UK market, it was foreseeable that, unless further steps were taken, it was likely that some Lecaent would be dispensed for pain. Ultimately the question came down to the "5%" of prescriptions written generically but indicating the pain indication, and the "steps" that had, by the date of manufacture, been taken. Was it foreseeable that pharmacists would dispense Lecaent when fulfilling those prescriptions?

Arnold J first considered the "steps" taken by Actavis, and he did so in relation to a cascade of dates on which he "assumed" batches of Lecaent had been manufactured - although it is only necessary to consider the first of those dates, namely mid-October to mid-December 2014.

Arnold J noted that soon after electing to launch Lecaent with a skinny label, Actavis decided to notify superintendent pharmacists that Lecaent was not licensed for the treatment of neuropathic pain. (By this time Warner-Lambert had sued Actavis for infringement). In view of these notifications, Arnold J.'s view was that any intentional administration of Lecaent for pain could properly be regarded as de minimis. Consequently, said Arnold J, it was not foreseeable that there would be any more than de minimis intent to infringe. Thus Actavis did not have the requisite mental element at the time of first manufacture, and so there was no threatened or later infringement by dealings in the medicine in the UK.

As the litigation proceeded, and the "steps" Actavis took to seek to avoid sales of Lecaent for pain only increased thereafter, none of the later batches infringed either.

Indirect infringement under section 60(2)

Arnold J then considered the question of indirect infringement. Section 60(2) of the Patents Act makes it an act of indirect infringement to supply or offer to supply in the UK the means relating to an essential element of the invention, for putting the invention into effect, where the requisite knowledge element is present.

Despite the Court of Appeal having overturned his first instance decision striking out Warner-Lambert's s.60(2) arguments, Arnold J gave short shrift to this argument for a second time. The judge addressed Floyd LJ's three reasons for overturning the first instance decision. He said he was "puzzled" by Floyd LJ's reference to the European Patent Convention (EPC) (since the law regarding infringement was derived from the Community Patent Convention (CPC) not the EPC). He was "baffled" by Floyd LJ's comment that while Warner-Lambert's s.60(2) claim might not add anything to its direct infringement claim, it was wrong to strike it out. And he simply did "not understand" Floyd LJ's third reason (which suggested the phrase "putting the invention into effect" may need closer scrutiny (again, to which we came back later)).

Having made those comments, Arnold J. dealt with this allegation very briefly, effectively just confirming his interim view:

"The fundamental difficulty with Pfizer's claim under section 60(2) remains, as it has always done, that claims 1 and 3 of the Patent are claims to processes of manufacture, but there is no act of manufacture by any party downstream from Actavis, nor even the prospect of an act....although there is no difficulty in concluding that Lecaent's active ingredient is "means, relating to an essential element of the invention for putting the invention into effect", Lecaent is not suitable for putting, or intended to put, the invention into effect: either the invention has already been put into effect by the time that Lecaent leaves Actavis' hands or it is not put into effect at all."

On that basis he found there was no indirect infringement.

Threats

Several communications sent by Pfizer in parallel with the ongoing litigation were considered to fall foul of the provisions of the Patents Act prohibiting threats, including a letter sent to superintendent pharmacists, a letter sent to clinical commissioning groups and a letter sent to the BMA.

Arnold J's findings on threats may well undergo further review in the higher courts. In the meantime, anyone considering written communications regarding patent defence in the pharmaceutical sector, particularly with entities and/or individuals in the public sphere, should study paragraphs [690]-[721] of Arnold J's judgment with care.

Declaratory relief

In view of the judge's conclusion that Actavis had not infringed the Patent and the extensive publicity attracted by the present case, Arnold J concluded that it would serve a useful purpose for the Court to clarify the position of doctors who prescribe generic pregabalin, pharmacists who dispense Lecaent and patients who take Lecaent, all of whom were also found not to infringe. The exact wording of the order was not dealt with in the judgment.

Commentary on Arnold J's approach and findings

Goodness - Where to start!

While this case now leaves the first instance court, at least on the question of liability, we suspect that there will be much more to come from the 'pregabalin' saga from the higher UK courts. With the recent celebrations of various WWII anniversaries fresh in the mind, a particular quote springs to mind:

"Now this is not the end. It is not even the beginning of the end. But it is, perhaps, the end of the beginning".

There are a number of points arising from Arnold J's judgment which appear open to debate. We set out some of these below:

Construction, Inventive Step and Insufficiency

Firstly, it is perhaps worth noting the relationship between Arnold J's analysis on construction, his finding on common general knowledge and his conclusions on inventive step and insufficiency.

Arnold J did not mention the more recent guidance provided by Sir Robin Jacob on the 'obvious to try' doctrine in Teva v Leo which has perhaps raised the bar for obviousness higher than just a "fair expectation" of success (our commentary on that case is available here).

The omission appears unlikely to have impacted the judge's decision on inventive step, which went in Warner-Lambert's favour.

However, Arnold J's construction of the word "treating" potentially raises questions in the context of both inventive step and sufficiency. He found that the claimed invention, in Swiss form, was to an effective therapy, yet the criterion for determining efficacy was 'success' merely in an animal model mentioned in the patent. The consequences of this interpretation raise the following questions:

  • Would positive data (or even a 'fair expectation' of positive data) from such a model render the claimed invention obvious, irrespective of whether pregabalin proved to be effective in the treatment of neuropathic pain in humans or animals?;
  • Are the results of Phase II and Phase III trials, by which efficacy is (or is not) established for the purposes of regulatory law, superfluous for the purposes of assessing the sufficiency of this patent?
  • Would the patent be infringed by using pregabalin to manufacture a medicament which was then tested in the models for neuropathic pain mentioned in the patent?

The second point would also seem to conflict with Arnold J's commentary on the context of and expectations regarding clinical trials in Hospira v Genentech III. These questions may be addressed further in the Court of Appeal.

Further, said Arnold J, even if there was, as Warner-Lambert asserted, sufficient data in the Patent to make it obvious to try pregabalin for neuropathic pain (from which it is presumed that this would be obvious to try in an animal model used in the patent), that was not enough for sufficiency. This suggests that the of plausibility standard for obviousness differs from the standard for sufficiency.

In Hospira v Genentech (I) [2014] EWHC 1094 (Pat) Mr Justice Birss noted (paragraph 121) that the extent of any difference was a question for another day. Some years ago, in Conor v Angiotech [2008] UKHL 49, Lord Hoffmann suggested that the tests ought to be aligned. He said:

"The Court of Appeal upheld the judgment of Pumfrey J on the ground that the patent contained no "disclosure" saying that taxol was specially suitable for preventing restenosis. Again, I agree that the description, though offering a theory (its anti-angiogenic properties) as to why taxol would prevent restenosis, did not offer any evidence that this would turn out to be true. If it had not turned out to be true, the patent would have been insufficient. But there is in my opinion no reason as a matter of principle why, if a specification passes the threshold test of disclosing enough to make the invention plausible, the question of obviousness should be subject to a different test according to the amount of evidence which the patentee presents to justify a conclusion that his patent will work."

The difference, if any, may yet be explored by the higher courts in the UK in the present dispute.

Whether the criterion for establishing efficacy is success in in vitro or pre-clinical models or success in clinical trials in humans or animals, it does not appear to have been in dispute in the present case that the skilled person would have been able to put the neuropathic pain invention into effect, or that it worked across the scope of the neuropathic pain claim.

Infringement

In its interim judgment, the Court of Appeal addressed Arnold J's refusal to award interim relief against Actavis in the present case. (Our commentary on the Court of Appeal's decision is available here.)

While the Court of Appeal confirmed Arnold J's decision not to award the relief sought on the 'balance of justice', it took the opportunity to issue guidance on the construction of the Swiss form claims in issue. Further, it overturned Arnold J's decision to strike out Warner-Lambert's claim for indirect infringement pursuant to section 60(2) of the Patents Act 1977. This is what Floyd LJ said in the paragraphs referred to by Arnold J. as support for his finding that the Swiss claims of the patent "are directed to the manufacturer":

"128. In reaching his conclusion that it was the manufacturer's intention that was determinative, the judge [Arnold J.] relied on what Jacob LJ said in Actavis v Merck at [75], namely that claims in Swiss form were aimed at the manufacturer and did not touch the doctor. I think the judge may have read too much in to this passage. Jacob LJ was there considering whether the claim was a disguised claim to a method of treatment. The inclusion of a manufacturing step ensures that it is not. Jacob LJ was not addressing the nature of the mental element in the claim. It is, I think, important to bear in mind that there are two mental elements involved: the question is what the manufacturer knows or foresees about the intentional use of the drug by the end user which counts.

129. .... How does one tell whether a manufacturer is using the manufacturing process of the claim, and therefore rendering himself liable for patent infringement? The answer must be when he manufactures pregabalin when he knows or foresees that users will intentionally administer it for pain."

This, and other parts of the judgment, would appear to suggest that Floyd LJ's key findings on construction were that in Swiss form claims (i.e. "Use of X in the manufacture of a medicament for the treatment of Y") the word "for" does not mean "suitable and intended for". Rather, such claims require knowledge (and for this purpose constructive knowledge is enough), or reasonable foreseeability, of ultimate intentional use for the claimed medical indication. Floyd LJ said that there was no requirement that the manufacturer must have that specific ultimate intention or desire himself - just the foresight that it will occur. As such, there was no evidential burden upon the patentee with regards to the manufacturer's subjective intent.

With that guidance from the Court of Appeal in mind, the question arises as to how it has been applied in this judgment. In particular, Arnold J's assessment of Floyd LJ's guidance on the construction of the word "for" in a Swiss claim, set out in paragraph 634 and cited in full above, is worth further scrutiny. Arnold J's conclusion in that paragraph, namely: "It is the element of intention which ensures novelty" does not appear to be borne out by a review of Floyd LJ's judgment. In particular, para 124 of Floyd LJ's judgment (a paragraph not highlighted by Arnold in his para 164) said the following:

"124 ...If a product is "for" a particular therapeutic indication if it is reasonably foreseeable that it will be used intentionally for the treatment of pain, then it will not be rendered lacking in novelty by showing that products in the prior art had been manufactured in circumstances when it was not possible to foresee such a result."

Contrary to Arnold's finding, this section appears to suggest that the foreseeability element is enough to ensure novelty.

Further, there could be said to be subtle differences between what Floyd LJ said in the paragraphs of his judgment referenced by Arnold J. in his paragraph 634, and the statements of principle which Arnold J. sought to extract from them, which may yet be explored by the Court of Appeal.

For example, Arnold J referred to "intentional administration" being at the heart of the invention, citing paragraph 121 of Floyd LJ's judgment in support. That paragraph of Floyd LJ's judgment does not use the phrase "intentional administration". It reads:

"... it is the intention for which the compound is administered which is at the heart of the invention ..."

In paragraph 122, Floyd LJ went on to propose that the word "for" in the claim acts as a link between the manufacture and ultimate intentional use of the drug, and then considered what is sufficient to constitute that link. He ultimately identified two options: 'foreseeability' and 'subjective intention'. In paragraph 123 he rejects the latter, and in paragraph 124 (cited above) suggests foreseeability does the trick.

Floyd LJ had, previously, used the phrase "intentionally administered" in paragraph [118], but that was when considering the "subject matter" of the claim in paragraph [118]. He also used the phrase when considering secondary infringement in paragraph [129] of his judgment:

"How does one tell whether a manufacturer is using the manufacturing process of the claim, and therefore rendering himself liable for patent infringement? The answer must be when he manufactures pregabalin when he knows or foresees that users will intentionally administer it for pain." (emphasis added)

But again, the "foreseeability" element would appear to remain the principal state of mind relevant to the manufacturer.

Finally, it is worth noting that Arnold J did not refer to Floyd LJ's paragraph 114, made in the context of considering whether any form of intention must be attributed to the manufacturer, where he observed that "a search for the appropriate meaning of "intention" which does not appear in the claim, is likely to throw one off the scent".

Ultimately, whether Arnold J's application of the Court of Appeal's judgment has had the effect Floyd LJ envisaged will no doubt be commented upon further by the higher courts, in due course. As regards the manufacturer, plainly the proper approach is 'foreseeability'. To what degree the “intention” element needs to be demonstrated remains uncertain.

An alternative interpretation of Floyd LJ's guidance could be, that the "intention" he referred to is merely the inherent intent to administer for pain which arises on any occasion a patient takes a pill to relieve his pain (as opposed to for a non-pain indication). This interpretation would not require specific intent in the mind of one individual (i.e. doctor, pharmacist) or team that Lecaent in particular be handed to a particular patient for the treatment of pain. It would mean that such administration was (in almost all cases) foreseeable - unless steps had been taken to seek to avoid dispensing the generic product for the patented indication. The assessment would then turn on what steps had, in fact, been taken, and whether they were sufficient to abrogate that foreseeability.

Indirect infringement

In the Court of Appeal, when addressing indirect infringement and in overturning Arnold J's decision to strike out Warner-Lambert's claim under section 60(2), Floyd LJ noted in paragraph 134 that the courts of two other European Patent Convention States appeared to consider that indirect infringement could arise in equivalent circumstances. He also indicated, in paragraph 135, that perhaps the phrase "putting the invention into effect" did not require just a single "event which, as a whole" amounted to the infringing act. This suggests that Floyd LJ was envisaging infringement of a Swiss form claim comprising a series of events.

He went on in paragraph 138 to note that

"...when section 60(2) speaks of "putting the invention into effect", it may be legitimate to look not just at whether any one person is carrying out the invention in a sense which would give rise to liability of that person for an act of infringement. It may be that the invention is put into effect if pregabalin is manufactured by one person and supplied to another who intentionally uses it for the treatment of pain. In those circumstances, a person who supplies pregabalin with the requisite knowledge (i.e. that prescribed in section 60(2) itself) does provide means suitable and intended to put the invention into effect, albeit by the combination of manufacturer and user, rather than by any one person alone."

In paragraph 139, Floyd LJ gave an analogy:

"An analogous problem arises where one step of a two-step process is carried out by A and the second step is carried out by B. Absent a claim of joint tortfeasance, could it not be said that by supplying the result of the first step to B, A is contributing to putting the invention into effect (by A and B together)?"

The fact, therefore, that the meaning of section 60(2), and particularly the phrase "putting the invention into effect", came under limited scrutiny in this judgment would appear to be another area the Court of Appeal may want to consider further.

Unlike the Court of Appeal's apparently obiter comments on the construction of Swiss form claims in the context of direct infringement, the Court of Appeal's decision to overturn Arnold's strike out of Warner-Lambert's claim of section 60(2) indirect infringement and Floyd LJ's associated comments (set out above) on the interpretation of s.60(2) would appear to have been ratio, and therefore binding on the lower court. The fact, therefore, that Arnold J declined the opportunity to explore the meaning of section 60(2), and particularly the phrase "putting the invention into effect", would appear to be a clear route to the Court of Appeal.

Concluding comment

It is to be expected that Arnold J's decision will be appealed and that the Court of Appeal will revisit the construction of Swiss form claims, particularly the mental element imported by the word "for"; the consequences of that construction for the analysis of infringement; and the meaning of the phrase "putting the invention into effect" in s.60(2).

It is to be expected too that Arnold J's finding that certain claims of Warner-Lambert's patent were insufficient in the present case will be revisited.

It is noteworthy that Arnold J's construction of the Swiss form claim in issue begs the question whether an invention claimed in Swiss form will only be construed as being the effective treatment in the specified medical indication with the specified drug if the patentee has included data from patient trials in the specification.

In June 2015, in Hospira v Genentech III, Arnold J ruled that Genentech's patent (Swiss form claims) was obvious in light of a paper reporting the existence, but not the results, of a phase III trial. As we noted in the context of that decision, that case served as a stark reminder of the difficult choice currently faced by the innovative pharmaceutical industry:

do you wait to file until you have sufficient data to demonstrate sufficiency/plausibility, risking the emergence of information on a trial which demonstrates activity and renders the invention 'obvious'? Or:

do you file earlier, with the risk that the patent/application is invalid for insufficiency?

Before Arnold J, Genentech fell foul of the former; Warner-Lambert has now fallen foul of the latter.

In an afterword to his judgment, Arnold J pleaded the need for a suitable system to address the problem of protecting the monopoly conferred by a second medical use patent. This is undoubtedly needed.

Complementary to this is also a need for a more holistic system integrating regulatory law governing the grant of marketing authorisation for medicines and rules governing the validity of a patent. This will require much broader cooperation at the European level.