Monday, April 13, 2015

Arbitrary Selection Is Not Inventive

Janssen Inc v Teva Canada Ltd / bortezomib (NOC) 2015 FC 247 Barnes J
            2,203,936 / bortezomib / VELCADE

In light of the difficulty that is sometimes caused by selection patents, Barnes J’s Bortezomib decision is very welcome as a paradigmatic example of the correct use of selection patent concepts to strike down an invalid selection patent. Of course, invalid selection is not an independent ground for patent invalidity: 2010 FCA 197 [33]. In Canadian law that an invention is a selection is said to inform the analysis of all grounds of invalidity [ibid 27]. In his decision, Barnes J has focused entirely on obviousness; this is how European (EPO Guidelines G.VII.12) and US law (737 F 3d 731, 739 (Fed Cir 2013); 738 F 3d 1337, 1344 (Fed Cir 2013)) deal with selection patents, and it is, in my view, the correct emphasis.

Bortezomib is a proteasome inhibitor which is useful in the treatment of cancer [4]. The asserted claims of the 936 patent are to the compound bortezomib, as well as its use to treat cancer and a dosage form [7]. The prior art 904 patent disclosed a genus of compounds that includes bortezomib [54]. That Patent also disclosed that the disclosed compounds are potent proteasome inhibitors [27]. Barnes J noted that this meant that the 936 patent is a selection from the 904 patent [27], but this holding as such played no role in his analysis. His basic point was that “A person of skill is not doing anything inventive when he chooses options provided in a prior patent to build a molecule that he expects will work” [40]. The 904 patent tells us that all the compounds within the genus are potent proteosome inhibitors; bortezomib is a compound within the genus; therefore any skilled person would have know that bortezomib was a potent proteosome inhibitor, even before the 936 specifically disclosed it as such.

Barnes J’s use of the word “inventive” is helpful here. Much of the confusion related to selection patents because the inventive step requirement is expressed in terms of obviousness. In some sense it was not obvious to select bortezomib out of the myriad compounds in the 904 genus. But the fundamental question is not whether the selection was obvious, but whether it was inventive. (Prior to codification in s 28.3, what is now known as the non-obviousness requirement was normally called the inventive step requirement. Obviousness is only the test for inventiveness. The drafting of the EPC is explicit on this point: see Arts 52(1) and 56.) It might not have been obvious to select bortezomib out of the range of proteasome inhibitors described by the 904 patent, but neither was it inventive; it is what the EWCA has called an “arbitrary” selection: Dr Reddy's [2009] EWCA Civ 1362 [52]. The codification of non-obviousness in s 28.3 in conjunction with the endorsement of the Windsurfing / Pozzoli framework in Sanofi 2008 SCC 61, [67] which focuses on the “inventive concept,” means that in Canada this question is now often framed in terms of defining the inventive concept. So, in Bortezomib there was a question as to whether the inventive concept is only the compound bortezomib, or also the properties of bortezomib [20]. If the inventive concept is only the compound, then it would not be obvious to select the particular compound from the genus; but if the inventive compound includes the properties, it is obvious that bortezomib is useful in the same way that all the members of the genus are useful. In my view it is not particularly helpful in this context to debate what the inventive concept might be. Focussing, as Barnes J did, on whether the patentee had done anything inventive, addresses the same point, but it is more straightforward and less likely to lead to error.

While it is not inventive to discover that bortezomib is a proteasome inhibitor, it might be inventive to discover that it is a particularly effective proteasome inhibitor in comparison with others in the genus. Thus the requirement that a valid selection patent have a “a special property of an unexpected character” or “a substantial advantage over the genus from which it was selected” [44] flows directly from the inventive step requirement. The argument that bortezomib was unexpectedly superior was made by Janssen, but it failed on the facts. There was simply no evidence that bortezomib was particularly effective [44], [46]. Indeed, neither the patent nor Janssen’s experts even asserted that it was particularly effective [47], [48].

Janssen had also argued that bortezomib was not in fact a selection from the 904 genus. If that were true, then it might be inventive to discover an entirely new compound which was a potent proteasome inhibitor; but this argument also failed on the facts: [54].

One point of note is that Barnes J quoted at length from Kane J’s Travoprost 2014 FC 699 decision, which he described as “a very similar situation” in which Kane J applied “classic obviousness principles” in concluding that the patent was invalid. I do not read the Travoprost decision in the same was as Barnes J. As discussed here, as I read it, Kane J’s analysis turned on her construction of the inventive concept. That is, the central question was not whether the species actually had special and unexpected properties, but whether the inventive concept, properly construed, included those properties. I considered Kane J’s analysis on this point to illustrate how a focus on the inventive concept can lead to an erroneous analysis. I do hope that I have misinterpreted her decision, and that Barnes J is right to say that it applied classic obviousness principles in the same way as did Barnes J himself.

Finally, while on the facts as found by Barnes J the identification of bortezomib was not sufficiently inventive to support a patent, we should recognize that the development of bortezomib was an important medical contribution. While the 904 application disclosed a genus of proteasome inhibitors, to actually treat cancer it is necessary to chose one and take it through clinical trials to regulatory approval. This case illustrates that patents alone may not provide a sufficient incentive in this respect. What if all of the members of the 904 genus are in fact equally effective? In that case it would be impossible to get a valid patent, and yet without a valid patent it would not be worthwhile to conduct the clinical trials necessary for marketing authorization. The facts of Bortezomib illustrate that a robust data protection regime is an essential complement to the patent system.

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