The long awaited decision on the merits in the well-publicised dispute between, inter alia, Generics (UK) Limited, Actavis Group and Warner-Lambert provides guidance on the steps that a generic company might take to avoid infringement of "Swiss form" patent claims when marketing a product with a "skinny" label.  

Arnold J applied the reasoning of the Court of Appeal, that a manufacturer who knows (including having constructive knowledge), or can reasonably foresee, the ultimate intentional use of a composition for a patented indication will infringe a Swiss form claim for that indication. He did so despite expressing "considerable doubts as to the correctness" of the test set out by the Court of Appeal.  

On the facts however, the Court concluded that at the time of manufacture of the generic product it was not foreseeable to Actavis that their product would be intentionally administered for the patented indication, save in a small number of exceptional "de minimis" cases. The patent was not therefore infringed.

Buisness Impact

  • The judgment has set out a framework for dealing with the infringement of Swiss form second medical use claims. It has sought to balance the monopoly rights conferred by second medical use patents whilst allowing generic competition for non-patented indications.
  • Generic companies might avoid infringement of Swiss form claims when marketing products for non-patented indications by using a skinny label and assisting health care providers and pharmacists to set up a system whereby the generic product will be prescribed and dispensed for non-patented indications only.
  • Companies intending to launch products with a skinny label, in the hope of avoiding patent infringement, should take care in preparing their own internal forecast documents as these may be held against them if they can be used to infer an intention for off-label use.
  • Patentees must exercise caution when writing to third parties to inform them of the patent position, that those letters do not constitute an actionable threat of patent infringement.
  • It is questionable whether, in cases such as these, the court will grant an injunction in general terms to prevent infringement.

Warner-Lambert Company LLC and (1) Actavis Group PTC EHF, (2) Actavis UK Limited, (3) Cadecus Pharma Limited and (4) Pfizer Limited and Secretary of State for Health [2015] EWHC 2548 (Pat). 

Background

Warner-Lambert markets pregabalin under the brand name Lyrica, for three different indications – neuropathic pain, generalised anxiety disorder and epilepsy. Patent protection for the drug product expired in 2013 but Warner-Lambert is proprietor of a second patent claiming the use of pregabalin for the preparation of a pharmaceutical composition for treating pain, in particular neuropathic pain. The scope of protection in that patent is set out in the form of a "Swiss form" claim.

Actavis sought to sell generic pregabalin in the UK with a "skinny label", i.e. they obtained marketing approval only for the non-patented indications. Warner-Lambert in turn filed suit for patent infringement. The case is the first detailed decision of the English courts on the meaning of Swiss form claims and has attracted a great deal of attention, in particular the earlier decision of Arnold J on an application for interim relief (Warner-Lambert I) and the Court of Appeal's decision on that application (Warner-Lambert CA) (see our e-Bulletin dated 1 June 2015, discussing the decision of the Court of Appeal and setting out the full background to the dispute).

In reaching his decision, Arnold J emphasised a point made in Warner-Lambert I, that this case is exclusively concerned with claims in Swiss form. Claims in so-called EPC 2000 form have a different scope of protection to claims in Swiss form (being product, rather than process claims) and so it should not be assumed that the reasoning in this dispute can be automatically applied to the claims of an EPC 2000 patent.

VALIDITY

Although most of the attention on this case has focused on questions of infringement, the Court also considered a counterclaim from Actavis, that the patent was invalid for lack of inventive step and insufficiency.

Inventive Step

After applying the classical test for inventive step, as set out in Windsurfing and restated in Pozzoli, Arnold J considered a more unusual point, which was whether common general knowledge has a territorial dimension. In particular, what happens when a fact is common general knowledge abroad, but not in the UK, a point that was left undecided by Floyd J in Teva UK Ltd v Merck & Co Inc [2009] EWHC 2952. Arnold J held that, at a minimum, it must be shown that the matter in question was common general knowledge in the UK. On the facts, none of the claims of the patent were found to be obvious.

Insufficiency

The obviousness challenge to the claims failed, however the insufficiency attacks were more successful, with claims 1, 3, 4, 6 and 14 found insufficient for excessive claim breadth. In particular, Arnold J held that i) nothing in the specification made it plausible that pregabalin would be effective for the treatment of the claimed pain type; and ii) based on the data in the patent it would be impossible for the skilled team to make any reasonable prediction that pregabalin would be effective for treating the claims that were directed towards to several types of pain, in the absence of a unifying characteristic.

INFRINGEMENT

Notwithstanding his decision on validity, Arnold J went on to consider whether the claims, if valid, were infringed.

Direct Infringement (s60(1)(c) Patents Act 1977)

The meaning of "treating"

The Court first considered the meaning of the word "treating" in the Swiss form claims. It was common ground that this amounted to a functional technical feature of the claim, i.e. the actual attaining of a therapeutic benefit is a technical feature of the invention. However, the parties debated whether such efficacy needed to be demonstrated in animal models or in human (Phase II) trials.

Arnold J accepted the position put forward by the defendants, that the criterion for efficacy was a positive result in one of the three animal models used in the patent. This was the only evidence presented in the specification and so, the Court held, the skilled person would understand that the patentee was relying on this as a predictor of efficacy. It was relevant that the claims were drafted broadly, rather than being directed to the treatment of humans.

The mental element

The Court then turned to the mental element of the Swiss form claims, that the use be "for" treating pain. This issue had been considered by the Court of Appeal in Warner Lambert CA (analysed in detail in our earlier e-bulletin). Floyd LJ, giving the leading judgment of the Court, had held that the word "for" required that the manufacturer knows or can reasonably foresee that the ultimate intentional use was for pain, not that he/she had that specific intention or desire him/herself (overturning Arnold J's ruling at first instance that infringement of a Swiss form claim required an intention on the part of the manufacturer that the product would be used for treating the patented indication).

Although Arnold J considered the relevant sections of Floyd LJ's decision to be obiter, he held that the reasoning should be considered to be highly persuasive and that he should follow it unless he was entirely convinced that it was wrong. On the facts, although he had "considerable doubts as to the correctness of Floyd LJ's interpretation", he was not entirely convinced that it was wrong. He also accepted (despite admitting to reservations) that the intention of the pharmacist is relevant. Generally, pharmacists do not know the indication for which a drug has been prescribed. However, where the pharmacist knows that the doctor has prescribed generic pregabalin for treating pain, and the pharmacist dispenses the generic product, there is intentional administration of the generic manufacturer's product to treat pain. The patient's intention was irrelevant.

Intention must be assessed at the time at which the product is manufactured, and accordingly such intention may change and develop over time. Looking at the foreseeability of off-label prescribing, Actavis accepted that they knew that a skinny label alone would not prevent pregabalin being dispensed for the treatment of pain. Accordingly, they decided to take a number of steps to inform third parties that Lacaent (their generic product) was not indicated for treating neutopathic pain. Those steps included:

  1. Informing pharmacists that Lacaent was not indicated for treating neuropathic pain;
  2. Writing to every CCH in England and every Health Board in Wales and Scotland and every Trust in Northern Ireland;
  3. Emphasising that Lecaent is not indicated for pain in their promotional materials; and
  4. Briefing their sales and telemarketing teams appropriately.

On the facts, the court considered infringement in three discrete time periods, in light of the steps taken by Actavis up to and including each time period.

At various stages in the build up to, during and after trial, Warner-Lambert contested that Actavis should have taken additional steps to prevent off-label prescribing, such as additional letters to pharmacists, hospitals or doctors, additional warnings on the packaging or changes to the software used by prescribing doctors. These steps were all rejected by Arnold J who placed emphasis on Actavis' own internal forecast documents, which showed an intention to avoid off-label sales.

On the facts, the Court found that no more than 5% of GPs routinely name the condition for which a drug is prescribed. The question then was whether it was foreseeable to Actavis that in the 5% of cases where the prescription indicated that pregabalin had to be prescribed for pain, the pharmacist would dispense the generic product, despite the fact that it was not licensed for pain.

Arnold J held that it was key that Actavis had notified superintendent pharmacists that their product was not licensed for the treatment of neuropathic pain. In the circumstances therefore it was not foreseeable to Actavis that their product would be intentionally administered for the treatment of pain, save in a small number of exceptional cases which the Court regarded as de minimis.

Indirect Infringement (s60(2) Patents Act 1977)

Warner-Lambert's claim for indirect infringement under s60(2) Patents Act 1977 had been struck out by Arnold J in Warner-Lambert I. Although the Court of Appeal agreed with him that there were difficulties with this claim because pharmacists were not "preparing a pharmaceutical composition" as required by the claims, they nonetheless allowed the claim to go to trial.

Arnold J, on revisiting this issue, held that the fundamental difficulty with the claim under s.60(2) was that no act of manufacture is performed by any party downstream of Actavis. The generic product is not therefore suitable for putting the invention into effect and so there was no indirect infringement.

Balance of Justice concerning Injunctions

With regard to the relief sought by Warner-Lambert, Arnold J observed that the grant of an injunction would be disproportionate and/or create barriers to legitimate trade because it would likely force Actavis to withdraw from the lawful market for the non-patented indications. As had already been observed by the Court of Appeal, in cases such as this, it might not be appropriate to grant an injunction at all.

THREATS

During the build up to the dispute, Warner-Lambert wrote a large number of letters to parties connected to the dispute, including the Department of Health, NICE and Superintendent Pharmacists.

Actavis counterclaimed that a large number of the communications made by Warner-Lambert amounted to threats under s.70 of the 1977 Patents Act. This section provides that where a person threatens another person with proceedings for patent infringement, that person may be aggrieved if the patentee cannot show that the threats are justified because of patent infringement. Communications conveying factual information about the patent do not amount to a threat.

Arnold J agreed that some of the letters written by Warner-Lambert would be understood by an ordinary reasonable person to be threats of a patent infringement action, and that those threats could not be justified by Warner-Lambert. In some cases, the threat caused harm to Actavis' commercial interests.

GENERAL REMARKS

In his concluding remarks, Arnold J proposed that the best solution to the problem of protecting second medical use patent monopolies, whilst allowing lawful generic competition for non-patented indications, is to ensure that prescribers write prescriptions by reference to the patentee's brand name for patented indications and by reference to the generic name for non-patented indications. This would require central and authoritative guidance that, realistically, is unlikely to materialise in the short term.