The pregabalin litigation is very far from over. As blogmeister Jeremy reported earlier this month, Mr Justice Arnold granted an injunction against Sandoz who were launching a full-label product, notwithstanding that he had considered the patent invalid in the decision now known as Warner-Lambert V (see posts here, here and here), because he had given permission to appeal and so there was a possibility that the Court of Appeal would find the patent valid.
That decision contained two other interesting pieces of information, as the judge reported:
The first is that on 16 October 2015 I gave both Mylan and Actavis on the one hand and Warner-Lambert on the other hand permission to appeal against my decisions with respect to insufficiency and I gave Warner-Lambert permission to appeal against my decision with respect to infringement under section 60(1)(c) (but not section 60(2)), subject to the qualification that I refused permission to appeal against my findings of fact. I gave the parties permission to appeal because I was satisfied that those appeals had a real prospect of success. Mylan has stated that it intends to seek expedition of its appeal. Actavis does not support expedition of the appeals, but Warner-Lambert does. It remains to be seen whether the Court of Appeal will order expedition, and when the hearing of the appeals will be fixed for.
The second development is that, in case both appeals on validity are unsuccessful, Warner-Lambert has launched a conditional application to amend the Patent. The proposed amendments fall into two categories. The first category consists of simple deletion of claims which were held to be invalid. Those proposed amendments are, as I understand it, uncontroversial. The second category consists of an amendment which does not amount to a simple deletion, but on the contrary, amounts to a re-writing of one of the existing claims. The proposed amendment is to what was claim 3 of the Patent and, following deletion of old claim 1, will become new claim 2. The amendment consists of adding to the end of the claim the words "caused by injury or infection of peripheral sensory nerves". The basis for that amendment is said to be the statement in  of the Patent that "Neuropathic pain is caused by injury or infection of peripheral sensory nerves".Now, just out, is the decision on the second development above - the conditional application to amend the patent, Generics (UK) Ltd (t/a Mylan) v Warner-Lambert Company LLC  EWHC 3370 (Pat). Presumably the Sandoz decision does not come under this numbering, so we can call the latest decision Warner-Lambert VI.
In a nutshell, Arnold J considered that there was no problem with the deletion of the invalid claims, but that the amendment to re-write claim 3 (relating to neuropathic pain) was an abuse of process. It would require a new trial to consider the allowability of the amendment. Therefore, the application was struck out as an abuse of the process of the court because because it could and should have been made prior to the original trial. He rejected Pfizer's argument that it was the victim of procedural unfairness on the part of Mylan and Actavis in not raising the point about central neuropathic pain earlier than they did. The judge noted:
It is true that the consequence (subject to the outcome of the appeals) will be that claim 3 is invalid and must be deleted, but that consequence is attributable to Warner-Lambert electing to defend the insufficiency attack on claim 3 in the way in which it did, which proved unsuccessful (subject to the outcome of the appeals), and not making a conditional application to amend before trial. As the cases show, Warner-Lambert is not the first patentee to have made that mistake.
What is interesting to this Kat is that of course it would have been open to Pfizer/Warner-Lambert to go to the EPO and seek the same amendment using the central limitation procedure. The patent was already amended using central limitation on 22 September 2014 to restrict to pregabalin only, the claims previously having recited a larger group of compounds. However, a limitation application cannot be conditional - if the limitation application is accepted, the patent will be amended. Also, limitation would have effect for all designated contracting states, not just the UK. So this would not give Pfizer the same procedural flexibility. What happens if an unconditional limitation application is now made before the appeal is over is not clear to this Kat - something similar happened in Samsung Electronics Co LTD v Apple Retail UK LTD & Anor  EWCA Civ 250 (reported by IPKat here), which made it clear that the central limitation route was permissible, but left it open to the Court of Appeal, once the limitation proceedings were concluded, to decide that the appeal proceedings might constitute an abuse of process. So probably one way or another the central limitation route cannot circumvent the current strike-out decision.
The first development reported above in the decision against Sandoz is the appeal and cross-appeal in the main case. This is referred to in  of the latest judgment, and this Kat, hoping for news of the appeal, was disappointed - Arnold J reports "I do not know when the appeals from Warner-Lambert V will be heard, and in particular whether they will be expedited by the Court of Appeal". This Kat very much looks forward to news of whether expedition is ordered.