Warner-Lambert v Generics Part 2: infringement

The UK Supreme Court’s ruling last week in a long-running patent dispute between Warner-Lambert and Generics UK (discussed here and here) brings welcome clarity, almost, to the questions of infringement of Swiss-form claims, and insufficiency for pharma patents.  But in the end it is a missed opportunity given the diverging views of the five judges involved and the absence of clearly stated principles.

Supreme Court decisions on patent law are unusual and very significant.  We will provide a fuller analysis of the implications of this ruling, but for now, here is an overview. We looked at the insufficiency issues in Part 1 of this series (Supreme Court eases patent pain for the NHS, but leaves confused answers for drug companies: Warner-Lambert v Generics Part 1). In Part 2 we turn to the issue of infringement of Swiss-form claims. Briefly, these are claims in the form:

“the use of compound X in the manufacture of a medicament for the treatment of indication Y”

to allow for patent protection where an existing medicine is repurposed to treat a new indication.

Infringement – is the packaging the final answer?

The Supreme Court did not have to deal with the question of infringement because they had ruled the patent invalid. But the trial judge and Court of Appeal had expressed fundamentally different views on infringement. The trial judge found the test was:

  • Did the manufacturer intend the medicine to be used for the second medical use?

The Court of Appeal, that  it was:

  • Would a reasonable manufacturer foresee that the medicine would, in practice, be used for the second medical use?

So the Supreme Court chose to address this. However, although all five judges agreed that there was no infringement, very different reasons were given.

Outward presentation test

The attractive clarity of the lead ruling brings a simple approach to determining infringement in relation to purpose-limited process claims. Essentially, the outward presentation of the product is key. For a pharmaceutical product, that means the formulation and dosage, packaging and labelling, and the patient information leaflet. This should be regarded as a public statement of the use for which the product is made. One of the three judges adopting this approach felt that in rare cases the context could make it obvious that this should not be taken at face value. If, for example, the quantities supplied made it clear that the medicine was intended for patent-protected indications, patent infringement might arise.

Subjective intent test

But unfortunately that isn’t the end of the story. Two of the judges did not adopt the same approach, leaving open the possibility that distributors and pharmacists could be liable under Swiss form claims without any external indicia to help them make this judgment.  For these judges, the right approach involves establishing the subjective intent of the manufacturer. 

In his judgment (choosing subjective intent as the test) Lord Briggs acknowledged the unacceptability of a test that could make a doctor or pharmacist liable for infringement when they could not know the manufacturer’s subjective intent. 

These differing approaches open up the prospect of distributors and dispensers being subject to uncertainty and confusion, and potentially threatening behaviour by patent-owners. It also invites complexity in infringement proceedings with the potential for evidence of over-supply, patterns of prescribing etc.  It is clear from all five judgments that the tribunal took the position of doctors and pharmacists into account. The judges recognised that a test that made these groups potentially liable when they did not or could not know the intent of the manufacturer was unjust. Indeed, none of the tests put forward result in a satisfactory balance between the public policy reasons behind patents.  Sadly, the panel could not agree on a satisfactory compromise, perhaps because, under current legislation, one does not exist.

A missed opportunity

While the NHS has been relieved of a lot of discomfort, and can now make use of generic pregabalin for treating pain, the question may well have to be revisited in respect of the many other second medical use patents which rely on Swiss-form claims.  We regret that neither sufficiency and infringement have been dealt with definitively. No doubt much of the difficulty the judges clearly have in reaching their conclusions arises from the rather artificial nature of Swiss-form claims. But we feel that the diverging views and lack of clear statements of principle do not help either patentees or potential infringers to understand the legal parameters within which they are operating.

We acted in the case on behalf of a pharmacist who intervened in the Supreme Court. We do not feel that the medicines distribution and dispensing network have been given the certainty they need. But the real problem is the inadequacy of the legislation the court was trying to interpret in the context of a form of claim not anticipated when the legislation was drafted.

Alasdair Poore and Mark Pearce

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Every piece of content we create is correct on the date it’s published but please don’t rely on it as legal advice. If you’d like to speak to us about your own legal requirements, please contact one of our expert lawyers.

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