Patents: Conor Medsystems Inc v Angiotech Pharmaceuticals Inc and Others

In his speech in Conor Medsystems Inc v Angiotech Pharmaceuticals Inc and others [2008] UKHL 49 (9 July 2008) Lord Neuberger opined that the House of Lords decision represented "a significant development in United Kingdom patent law" but I am not sure that is true. Certainly he was right to say that the Lords differed from the views of highly experienced patent judges (Mr Justice Pumfrey at first instance and Lord Justice Jacob in the Court of Appeal) but my surprise having read Lord Hoffmann's speech is that anyone was surprised. 

Of course, I say that with the benefit of hindsight but I think I would have reached the same conclusion had I seen the paragraph of counsel's skeleton argument that appears to have led the trial judge and appeal court into error. The paragraph submitted that the inventive concept was not what claim 1 of the patent claimed, namely:

"A stent for expanding the lumen of a body passageway, comprising a generally tubular structure coated with a composition comprising an anti-angiogenic factor and a polymeric carrier, the factor being anti-angiogenic by the CAM assay, and wherein said anti-angiogenic factor is taxol, or an analogue or derivative thereof."

but purportedly the idea of seeking to treat or prevent restenosis by coating a stent with a taxol/polymer composition. Having misrepresented the invention the claim was rubbished: 

"The disclosure is of no more than this. The idea is not shown to work (either in humans or in animals), nor to work to any particular extent, nor to work with any particular polymer nor with any particular amount of drug. The invention thus lies in the idea of trying some, one or more, taxol/polymer combinations to determine whether restenosis can thereby be treated. It is at this level of generality that inventiveness must be assessed."

Lord Hoffmann described that submission as 

"an illegitimate amalgam of the requirements of inventiveness (article 56 of the EPC) and either sufficiency (article 83) or support (article 84) or both".

On the face of it his lordship seems to have had a point.

The test for obviousness is well settled and straightforward.  It is whether the invention would have been obvious to a skilled person in the art. Essentially that is a question of fact   A well established methodology for applying that test first formulated by the Court of Appeal in Windsurfing International Inc. v Tabur Marine (Great Britain) Ltd, [1985] RPC 59 and restated recently by the Court of Appeal in Pozzoli Spa v BDMO SA [2007] EWCA Civ 588. All that was required of the courts below was to apply that methodology.

Instead Mr Justice Pumfrey accepted the argument of the claimants uncritically that the patentee claimed nothing more than "the testing of a taxol-loaded stent to see if it is of any use in the treatment or prevention of restenosis". On that premise he was able to find the patent bad for obviousness because the evidence showed "that a skilled man would consider taxol to be worth testing to see what its properties were." On appeal Lord Justice Jacob accepted that conclusion at face value: 

"What the Judge is saying overall is that taxol would be included, along with other anti- mitotics, in a list of "other" anti-replicate drugs. And because the patent has not in any way demonstrated that taxol actually works to prevent restenosis, it is obvious in that sense."

On the strength of that reasoning he dismissed the appeal.

All five law lords agreed with Lord Hoffmann in rejecting that approach. In so doing, they reached the same view as the District Court of the Hague in a similar case on the same European patent.