Patents: Merck Sharp & Dohme Corp v Teva UK Ltd

In my article "Divided by a common language: US and UK patent law" which was published in Science, People & Politics (April to June 2011) I noted that one of the differences between US and UK patent law was that 35 USC 102 (b) of the US act permits an application for a US patent even where the invention has been described in a publication or application for a foreign patent that has been made in the last 12 months. In England such publication would be prior art. Right on cue a case that illustrates the point is the decision of the Court of Appeal in Merck Sharp & Dohme Corp. v Teva UK Ltd. [2011] EWCA 382.

This appeal from the decision of Mr. Justice Floyd in Teva UK Ltd v Merck & Co, Inc [2009] EWHC 2952 (Pat) (20 Nov 2009). [2010] FSR 17 was in respect of an application by Teva UK Ltd. ("Teva") for the revocation of Merck Sharp & Dohme Corp ("Merck")'s European patent no. 0509752 on grounds of obviousness. The patent in suit was for "ophthalmic compositions comprising combinations of [MK 507] and [timolol]" for the treatment of glaucoma which had been filed on 17 April 1991. Six days earlier one George Nardin and other representatives of Merck had published a paper in the attendees' materials for the annual meeting of the Association for Research in Vision and Opthalmology in Sarasota, Florida that related to the additive effect in reducing IOP [intraocular pressure] of administering an eye-drop including 2% of a drug then known as MK 507 some ten minutes after the administration of an eye-drop containing 0.5% of a drug called timolol. The paper suggested, on the basis of experimental tests carried out on humans over a period of 8 days, that such consecutive administration improved reduction of intraocular pressure (that is to say, glaucoma) by about 17%. Teva had argued successfully before Mr. Justice Floyd that the invention was obvious in view of the conference paper.

At trial, Merck had applied to amend its patent to meet Teva's objections but the judge took the view that the patent would be invalid even if it was amended in the way proposed by the patentee. Merck applied for permission to appeal against the trial judge's finding of obviousness in respect of one of the proposed amended claims. The Court of Appeal allowed Merck to appeal on the following ground:

"Further the learned judge failed to deal adequately or at all with [Merck]'s case that the step by step project proposed by [Teva] as the obvious way forward would not arrive at a formulation with the features called for by the independently valid claims, even if it was not abandoned outright. In particular the learned judge addressed the possibility that the skilled person would abandon the project but he failed to consider the impact on the later steps in [Teva]'s step by step approach of the outcomes of the tests [Teva] contended would be performed at earlier steps. [Teva] needed to establish that the outcome of its step by step approach would be a formulation formulated at a pH range of 5.5-6.0 required by proposed amended claim 18 and (or) with the amounts of the two drugs such that the concentrations fell within the scope of the claims, and in particular claim 6. [Teva] failed to do so. Although the judge expressed the conclusion that the use of a formulation within claim 6 does not involve an inventive step his reasoning does not adequately support that conclusion. The correct conclusion is that the claims are not obvious on this basis."

As the Court had refused permission to appeal on other grounds the only issue before their lordships (Sir Andrew Morritt, the Chancellor of the High Court and Lord Justices Richards and Patten) was "whether Teva had established that the outcome of its step by step approach would be a formulation of timolol and dorzolamide in the proportions specified in claim 6 at a pH range of 5.5-6.0 as required by proposed amended claim 18."

The crux of Merck's argument was that a skilled addressee could not possibly have come up with the patented invention within the 6 days between the publication of the conference paper and the application for the European patent. The Court of Appeal rejected that submission on the ground that neither the test for want of novelty nor the test for obviousness imposed a minimum time limit between the publication of the invalidating matter and the patent application. As the Chancellor put it at paragraph [36]:

"There is no additional time requirement in that case either. If by reference to the relevant state of the art the invention is obvious then it matters not that it may take time to perform the necessary routine tests. It is a matter of simple comparison between the relevant art and the claimed invention."

The trial judge had applied the correct test of obviousness referring to Hallen v Brabantia [1989] RPC 307; St Gobain v Fusion Provida [2005] EWCA Civ 177, Conor v Angiotech [2008] RPC 28, [2008] UKHL 49 and Pozzoli v BDMO [2007] EWCA 588, [2007] FSR 37. His approach to this case could not be faulted.

Since the leading judgment was delivered by the Chancellor, I should like to add that Sir Andrew Morritt is a lovely tribunal. I remember appearing before him in Newcastle once when he was Vice-Chancellor of the County Palatine of Lancaster. I had settled a rather iffy passing off or breach of confidence action with one of the local silks and the terms of settlement required a mention to the court. Knowing that he had a very heavy list I opened with the words "I regret that I have to inform your lordship"....... his face dropped, " ...... that my lord will be deprived of the pleasure of deciding a most interesting point of law". Beaming again, he replied "I'm sure we can live with that."