Swiss-style Patent Claims, Skinny Labels and the NHS

This article was produced by Olswang LLP, which joined with CMS on 1 May 2017.

Warner-Lambert (Pfizer) and Actavis (and others..)

Summary

In an interesting series of recent decisions, Mr Justice Arnold has considered the scope of Swiss-style second medical use patent claims and the interplay of these with practices in the UK healthcare system, such as skinny label authorisations and generic prescriptions. In the most recent instalment, he has granted an unprecedented Order requiring the NHS to take certain actions to reduce the likelihood of generic versions of pregabalin being sold for indications covered by Warner-Lambert's second medical use patent. These are the first UK Court decisions to look at these significant issues relevant to market entry of generic products where the only patent protection remaining for a blockbuster drug is in relation to a specific use or uses.

The Decisions

In recent preceding decisions, Arnold J refused to grant an interim injunction to Warner-Lambert against Actavis and, subsequently, refused Actavis' request to dismiss Warner-Lambert's infringement claim. However, he has now granted an Order in relation to NHS England in favour of Warner-Lambert. The full trial for validity and infringement of Warner-Lambert's patent will be heard in June.

The drug at the centre of the case is pregabalin, which Pfizer markets for epilepsy, generalised anxiety disorder (GAD) and pain, particularly neuropathic pain. Lyrica ® is currently Pfizer's biggest selling product, with global sales of about $4.6 billion in 2013.

Both the main compound patent and data exclusivity for pregabalin have expired. The only relevant patent protection still in force, and the patent Warner-Lambert seeks to enforce against Actavis and others, is a Swiss-style second medical use patent to pregabalin for treating pain.

Following expiry of Warner-Lambert's exclusivity, Actavis and others have applied for "skinny label" marketing authorisations for pregabalin to the non-patented indications of GAD and epilepsy and Actavis intends to market their product as Lecaent ®.

Warner-Lambert's concern is that this and other generic versions of pregabalin will in practice be sold for the treatment of pain.

This concern stems from practice in the UK healthcare system where approximately 83% of prescriptions are written generically and 95% of prescriptions do not state the indication for which the drug has been prescribed.

On this basis, Warner-Lambert sought an interim injunction against Actavis. The significant terms of the injunction required Actavis to 1) agree with any pharmacy they supplied that the pharmacy shall use reasonable endeavours not to supply or dispense LecaentTM to patients who have been prescribed pregabalin for the treatment of pain and 2) to package all Lecaent ® with a removable notification stating "this product is not authorised for the treatment of pain and must not be dispensed for such purposes".

In deciding whether to grant the injunction, Arnold J considered the scope of Swiss-style medical use claims and whether there was a serious issue to be tried. Warner-Lambert's contention was that to infringe the second medical use claim it was enough that Actavis knew that some Lecaent ® would inevitably be used to treat pain, even if Actavis did not intend for that to happen. However, Arnold J disagreed and found that there must be some subjective intent on Actavis' part in order to infringe the purpose limited claim. A subjective intent had not been alleged and on this basis Arnold found there was no serious issue to be tried.

In case he was wrong in this finding, Arnold J also then considered which course was likely to case the least irremediable prejudice to one party or the other. With respect to Warner-Lambert he considered what mattered was the likelihood of irreversible price depression in the market for pregabalin for treating pain and found that this was unlikely to be significant. In terms of unquantifiable and irreparable harm to Actavis, Arnold found that Actavis was likely to suffer such harm through 1) deterring pharmacists from stocking Lecaent ® by the contractual obligations of the proposed injunction and 2) delaying Actavis' entry to the market as a result of the injunction's packaging obligations. For these reasons, Arnold J refused to grant the injunction against Actavis.

In the same decision, Arnold J also commented that the best solution to the problem would in fact be if the NHS issued appropriate guidance indicating that doctors prescribing pregabalin for pain should use the brand name Lyrica ®.

In view of this position, the most recent decision is perhaps unsurprising, although it is unprecedented. Arnold J has issued an Order requiring NHS England to issue guidance to all GP practices and pharmacies immediately stating that the drug pregabalin should only be prescribed for the treatment of pain under Pfizer's brand name Lyrica ®, and not using the generic name pregabalin. This does indeed seem a neater solution and has the clear benefit that it will be effective in relation to all brands of generic pregabalin, not just Actavis' version.

The full trial for validity and infringement of Warner-Lambert's patent will be heard in June and, as Arnold J commented in one of the recent decisions, the issues under consideration are important and may well benefit ultimately from Supreme Court guidance.