Saturday, July 23, 2016

Blogging Break

I'll be on vacation for a couple of weeks. I'll resume blogging when I get back, starting with any cases I might have missed while I was away.

Wednesday, July 13, 2016

Another Twist on Blinding the Expert

Bristol-Myers Squibb v Teva 2016 FC 580 Mactavish J
            2,250,840 / 2,317,736 / atazanavir / REYATAZ

In a number of recent cases (see here), the parties have tried “blinding” their experts from certain facts in a laudable attempt to reduce the problem of hindsight bias. The Atazanavir decision raised another twist on this practice, which is this subject of today's post. For an overview of the facts, see this post, which also discusses some of the issues related to obviousness; and see this post discussing claim construction.

The point arose in the context of the 840 patent, which claims atazanavir. One of Teva’s experts on obviousness, Dr Romero, was blinded perhaps even more thoroughly than in most previous cases:

[192] Dr. Romero was not told the name of the drug that was at issue in this proceeding, other than the fact that it was a protease inhibitor, nor was she told the names of the parties. She was also asked not to carry out any independent research that might identify the drug in question.

That is, it seems that Teva tried to place Dr Romero in the place of the notional skilled person, trying to solve the problem facing the inventors, without knowledge of their solution. There are a couple of caveats even to this degree of blinding. One is that an expert like Dr Romero cannot forget her own current knowledge, and to the extent that she is familiar with approaches that would not have been common knowledge at the time, she cannot fully avoid the effects of hindsight, even when blinded to the particular facts. Also, as Mactavish J pointed out, “Dr. Romero was provided with a limited selection of the prior art that had been ‘cherry-picked’ by Teva, and her evidence has to be viewed with this in mind” [193]. This point was not merely theoretical; Mactavish J expressed concern that Dr Romero had only been provided with papers dealing with an azapeptide backbone, the class which atazanavir belongs to, and not prior art dealing with other possible backbones [194].

With those caveats, no approach is perfect and this heightened degree of blinding seems to be helpful in avoiding hindsight bias. However, it did not help Teva win its case. The details of Dr Romero's evidence were not spelled out by Mactavish J, but it seems the gist was that there were a finite number of modifications that the POSITA would have made in trying to make a better protease inhibitor [212]. However, Dr Romero proposed some modifications to the backbone which would never have led to atazanavir [195], and

[211] Dr. Romero does not identify which compounds or which substitutions should be made to obtain an improved protease inhibitor in her evidence, or how the POSITA should prioritize them. Importantly, Dr. Romero never states that the POSITA would make the substitutions necessary to get to atazanavir.

In the end, Dr Romero’s evidence may have hurt Teva’s case as much as it helped. The 840 patent survived the obviousness attack, and was ultimately held to be valid.

The fact that blinding the expert did not help Teva in this case helps confirm the value of the practice. If a witness blinded in this manner had arrived directly at the claimed invention, it would seem to be good evidence that the invention was obvious. (Though even this degree of blinding would not be conclusive, in light of the caveats noted above, as well as Locke J’s observation in 2016 FC 382 [46].)

Tuesday, July 12, 2016

A Summary Judgment Procedure under the NOC Regulations?

Janssen Inc v Celltrion Healthcare Co, Ltd 2016 FC 651 Hughes J
            2,261,630 / infliximab / INFLECTRA / REMICADE

This decision marks either a straightforward application of s 5(1) of the NOC Regulations, or a procedurally innovative use of s 6(5)(b) of the Regulations to effectively allowing a summary disposition of an NOC proceeding. Unfortunately, Hughes J was writing under a time constraint [1], and the decision is brief and some key facts are not clear (at least to me).

Janssen’s 630 patent covers the use of infliximab in treating rheumatoid arthritis [28]. Celltrion had already received an NOC for rheumatoid arthritis and related indications (the RA indications) based on a NDS filed before the 630 patent was granted, and so it did not have to address the 630 patent at that time [8]. (An infringement action is now underway [9].) Then, after the 630 patent was granted, Celltrion sought an NOC for indications related to inflammatory bowel disease (the IBD indications) [10]. Hughes J stated that “Celltrion was required to address the 630 patent under [the PMNOC Regulations].” Celltrion sent an NOA to Janssen, which then brought an application for an order of prohibition [10]. In response, Celltrion brought a motion under s 6(5)(b) asking that Janssen’s application be dismissed as an abuse of process, evidently on the general ground that the 630 patent did not cover the indications for which the NOC was being sought..Celltrion’s motion was granted by Aalto J.

Hughes J affirmed in brief reasons, in part adopting Aalto J’s reasons as his own [25]. But Hughes J also went to on to rely on Biolyse 2005 SCC 26 to conclude that “in a case such as the present one, where a patent claims a particular use of a drug it is that use that must be compared with the intended use by the generic and not just the drug” [27].

My difficulty with this case is that it is not entirely clear to me whether Celltrion was comparing its product with Janssen’s in seeking its NOC. Celltrion’s application was apparently based on an SNDS, not an ANDS or SANDS [10], and there is no suggestion in Hughes J’s reasons that Celltrion was comparing its drug to Janssen’s. If Celltrion was not comparing its product with Janssen’s, then the reasoning in the case strikes me as a bit odd. Biolyse held that it is only necessary to address patents on the register if the party submitting the application for an NOC compares its drug with that of the another drug against which the patent is listed. In other words, a party who is relying on their own data does not need to address the listed patents, even if the submission is for the same indications; it is only “copy-cats” who need to address listed patents. This was affirmed by the subsequently amended s 5(1), which says patents listed against a drug must be addressed only if “the submission directly or indirectly compares the drug with, or makes reference to, another drug.” (See also the RIAS to the 2006 amendments, SOR2006-242 at 1519-20.) So, if Celltrion was not comparing its product to Janssen’s then it would follow directly from per s 5(1) that it would not be required to address the 630 patent at all, even if the 630 patent was listed against infliximab, and even if Janssen’s NOC covers the IBD indications. The puzzle is that on this view of the decision, it is not clear why “Celltrion was required to address the 630 patent under [the PMNOC Regulations]” [10] in the first place.

On the other hand, if Celltrion was comparing its drug to Janssen’s for the IBD indications, that would explain why Celltrion was required to address the 630 patent. In that case Biolyse would not be directly applicable, as Celltrion’s product would be a “copy-cat” drug, in the sense of relying on Janssen’s data, even if Janssen’s data were for an unpatented indication. On those facts, Hughes J’s holding would not be a direct application of Biolyse, but rather an extension, which would mean that a generic need not address a listed patent even if the generic is indeed piggy-backing off the data submitted by the patentee, so long as the indication for which an NOC was sought did not infringe. Normally that would require an NOC proceeding based on an allegation of non-infringement pursuant to s 5(1)(b)(iv)t, but perhaps the motion under s 6(5)(b) was based on the view that the non-infringement issue was so clear that it would be an abuse to proceed with the NOC proceeding. In other words, s 6(5)(b) was being used for a summary disposition of the NOC proceeding. If that is what happened, then the decision is procedurally quite significant.

Friday, July 8, 2016

A Teaching Example on Claim Construction

Bristol-Myers Squibb v Teva 2016 FC 580 Mactavish J
            2,250,840 / 2,317,736 / atazanavir / REYATAZ

My previous post gave an overview of the facts of this decision and discussed some of the issues related to obviousness. This post discusses a tricky claim construction issue that arose in the context of the 736 patent. While it did not raise any new legal issues, it is a good example of the tension between the primacy of the claims and the principle that purposive construction requires that the claims are read in the context of the specification as a whole.

Monday, July 4, 2016

Discovery of Something Unexpected about Something Obvious

Bristol-Myers Squibb v Teva (NOC) 2016 FC 580 Mactavish J
            2,250,840 / 2,317,736 / atazanavir / REYATAZ

In this NOC proceeding Mactavish J held Novartis’ 840 patent, which claims the compound atazanavir [53], to be valid in the face of obviousness and anticipation attacks, while she held BMS’s 736 patent, which claims the bisulfate salt of atazanavir [273], to be obvious. A central dispute between the parties in respect of both patents was whether the inventive concept of the claimed inventions comprised just the compound itself, as Teva argued, or the compound and all its properties, as the patentees argued. The idea is that the more properties that are part of the inventive concept, the less likely it is that they will all be predictable, and so the less likely it is that the patent will be held obvious. In this post, I will argue that this idea is wrong; the number of properties in the inventive concept does not affect how likely it is that the claimed invention will be held to be obvious. In another post I will suggest that multiplying the inventive concepts might actually make invalidity more likely. The 736 patent also raised a very tricky claim construction problem, which I will discuss in a subsequent post.

Atazanavir is used in the treatment of HIV/AIDS. The first class of anti-HIV drugs were known as nucleotide reverse transcriptase inhibitors (or NRTIs) [13]. While these had potent activity against HIV, they were susceptible to the evolution of drug resistance and had unpleasant side-effects [14], [15]. A new class of anti-HIV drugs was developed, known as protease inhibitors [16]. These has a number of advantages over NRTIs, but the first generation protease inhibitors had poor bioavailability, which resulted in poor compliance and a consequent potential for the development of drug resistance [22]. There was therefore a strong motivation to develop second-generation protease inhibitors [23]. One of these was atazanavir, which came on the market in 2003 and which remains one of the best second generation protease inhibitors [24-25]. The 840 patent, which claimed atazanavir and its salts, disclosed only the free base form. While the free base had good inherent bioavailability, it was not sufficiently orally bioavailable in solid form to be a viable product [266-67]. The problem facing the inventors of the 736 patent was to develop a form of atazanavir having properties suitable for an oral pharmaceutical dosage form, including improved oral bioavailability [268]. They performed a salt screen, and solved the problem with the bisulfate salt which was claimed in the 736 patent. (Ciba-Geigy, which became Novartis, developed atazanavir, and BMS acquired the rights to atazanavir from Novartis and then developed atazanavir bisulfate.)