Sanofi-Aventis v. Apotex Inc.

Sanofi-Aventis v. Apotex Inc.
Court (s) Database
Federal Court of Appeal Decisions
Date
2013-07-24
Neutral citation
2013 FCA 186
File numbers
A-7-12
Notes
Reported Decision
Decision Content
Date: 20130724
Docket: A-7-12
Citation: 2013 FCA 186
CORAM: NOËL J.A.
PELLETIER J.A.
GAUTHIER J.A.
BETWEEN:
SANOFI-AVENTIS
Appellant
and
APOTEX INC.
Respondent
BETWEEN:
SANOFI-AVENTIS and
BRISTOL-MYERS SQUIBB SANOFI
PHARMACEUTICALS HOLDING PARTNERSHIP
Appellants
and
APOTEX INC.
APOTEX PHARMACHEM INC. and
SIGNA SA de CV
Respondents
Heard at Toronto, Ontario, on January 28, 2013.
Judgment delivered at Ottawa, Ontario, on July 24, 2013.
REASONS FOR JUDGMENT BY: PELLETIER J.A.
CONCURRED IN BY: NOËL J.A.
CONCURRING REASONS BY: GAUTHIER J.A.
Date: 20130724
Docket: A-7-12
Citation: 2013 FCA 186
CORAM: NOËL J.A.
PELLETIER J.A.
GAUTHIER J.A.
BETWEEN:
SANOFI-AVENTIS
Appellant
and
APOTEX INC.
Respondent
BETWEEN:
SANOFI-AVENTIS and
BRISTOL-MYERS SQUIBB SANOFI
PHARMACEUTICALS HOLDING PARTNERSHIP
Appellants
and
APOTEX INC.
APOTEX PHARMACHEM INC. and
SIGNA SA de CV
Respondents
REASONS FOR JUDGMENT
PELLETIER J.A.
INTRODUCTION:
[1] Plavix is a very successful anti-coagulant drug which was developed, patented, and marketed by the appellant, Sanofi-Aventis (Sanofi). Apotex Inc. (Apotex), a well known manufacturer and distributor of generic drugs, attempted to create and market its own version of the active ingredient in Plavix, clopidogrel bisulfate (clopidogrel). It applied for a Notice of Compliance from the Minister of Health, alleging that its version of clopidogrel did not infringe Sanofi’s patent which, it alleged, was invalid in any event for a number of reasons, including obviousness. Sanofi responded by applying to the Federal Court for an order prohibiting the Minister from issuing the Notice of Compliance to Apotex. That application was successful so that Sanofi continued to enjoy a monopoly with respect to the manufacture and sale of Plavix: Sanofi-Synthelabo Canada Inc. v. Apotex Inc., 2005 FC 390, [2005] F.C.J. No. 482 (QL). Appeals to the Federal Court of Appeal, Sanofi-Synthelabo Canada Inc. v. Apotex Inc., 2006 FCA 421, [2006] F.C.J. No. 1945 (QL), and to the Supreme Court of Canada, Apotex Inc. v. Sanofi-Synthelabo Canada inc., 2008 SCC 61, [2008] 3 S.C.R. 265 (Plavix), were unsuccessful.
[2] Apotex then commenced an action in the Federal Court seeking a declaration that Sanofi’s patent, Canadian Patent No. 1,336,777 (the ‘777 Patent) was invalid. Sanofi replied by commencing its own action, alleging that Apotex had infringed its patent by importing clopidogrel into Canada from Mexico and then exporting it from Canada for sale in other countries including the United States. The two actions were consolidated and were heard by Boivin J. (the Trial Judge or simply, the Judge). Following a 26 day trial, the latter found that the ‘777 Patent was invalid for lack of utility on the basis that the promise of the patent had neither been demonstrated nor soundly predicted. In addition, the Trial Judge found that the invention described in the patent was obvious. Though the Trial Judge also found that Apotex had infringed the ‘777 Patent, that finding was overtaken by his conclusion that the patent was invalid. The Trial Judge’s decision is reported as Apotex Inc. v. Sanofi-Aventis, 2011 FC 1486, [2011] F.C.J. No. 1813 (QL), (Reasons).
[3] This is an appeal of that decision. It raises a variety of issues including the promise of the patent, obviousness, and the limitation period applicable to certain acts of patent infringement.
BACKGROUND
[4] The following factual background will provide context for the analysis which will follow.
[5] The ‘777 Patent is a selection patent which means that it claims a subset of compounds which are already within the scope of another patent, Canadian patent 1,194,875 (‘875 Patent). I can do no better, in terms of describing the relationship of the patents and compounds in issue, than to quote paragraphs 3 to 6 of the Supreme Court’s decision in Plavix:
3 The parties have accepted that the Sanofi respondents ("Sanofi") are the relevant holders of patent 1,194,875 (‘875 Patent). This patent disclosed a genus or class of compounds useful in inhibiting platelet aggregation activity in the blood which is important in treating coronary artery, peripheral vascular and cerebral vascular diseases. This genus patent discloses over 250,000 possible different compounds useful for this purpose. One of the compounds is a racemate described as methyl alpha-5 (4,5,6,7-tetrahydro (3, 2-c)-thieno pyridyl) (2-chlorophenyl)-acetate (the "racemate").
4 A racemate is a substance containing equal amounts of two structurally different compounds, called enantiomers or optical isomers. The two isomers, the dextro-rotatory isomer and the levo-rotatory isomer, are mirror images of each other and rotate plane-polarized light in opposite directions.
5 The parties have accepted that Sanofi is also the relevant holder of subsequent Canadian patent 1,336,777 (‘777 Patent), the patent in suit. It discloses and claims clopidogrel bisulfate, which is marketed by Sanofi under the trade name of Plavix as an anti-coagulant that inhibits platelet aggregation activity in the blood.
6 Clopidogrel bisulfate is encompassed within the scope of the claims in the ‘875 Patent. Clopidogrel is the dextro-rotatory isomer of the racemate, having beneficial properties over both the racemate and the levo-rotatory isomer. The dextro-rotatory isomer exhibits a platelet aggregation inhibiting activity and is less toxic and better tolerated than the levo-rotatory isomer and racemate. The salts of the dextro-rotatory isomer, such as clopidogrel bisulfate, have a better therapeutic index than the salts of the racemic mixture and in fact, the levo-rotatory isomer exhibits almost no platelet aggregation inhibiting activity, and its toxicity is markedly higher than that of the dextro-rotatory isomer.
[6] While there are differences in the evidence which was before the Supreme Court in the Notice of Compliance proceedings (which gave rise to the Plavix decision) and the evidence in this action, none of those differences affect the accuracy the Supreme Court’s description of the relationship of the compounds in issue and their structure.
The ‘777 Patent
[7] The issues raised by this appeal require an understanding of the ‘777 Patent.
[8] The patent begins with a description of its subject matter:
The present invention relates to the dextro-rotatory enantiomer of methyl alpha-5 (4,5,6,7-tetrahydro (3,2-c) thieno pridyl) (2-chorophenyl)-acetate, a process for its preparation and pharmaceutical compositions containing it.
[9] Following a description of the formula of the invention, the patent describes its advantages:
In an unexpected manner only the dextro-rotatory enantiomer Id exhibits a platelet aggregation inhibiting activity, the levo-rotatory enantiomer Il being inactive. However, the inactive levo-rotatory enantiomer Il is the less well tolerated of the two enantiomers.
The invention also relates to the addition salts of the compounds of formula (Id) with pharmaceutically acceptable mineral or organic acids.
[10] The patent then describes the processes by which the invention can be made, setting out detailed instructions by which the enantiomer can be separated from its racemate and a suitable salt obtained.
[11] The next section of the patent is entitled “Pharmacological Activity”. In it, one finds a comparison between the compound of the ‘777 patent and the racemic mixture from which it was derived with respect to platelet inhibiting activity and toxicity. Platelet aggregation studies in rats showed that the levo-rotatory isomer is inactive and that the dextro-rotatory isomer is at least as active as the racemate. A test of anti-thrombotic activity showed that the levo-rotatory isomer showed no anti-thrombotic activity whereas the racemate and the dextro-rotatory isomer did. Toxicity studies in rats showed that the toxicity of the racemic mixture was similar to that of the levo-rotatory isomer while the dextro-rotatory isomer is markedly less toxic.
[12] This section concludes as follows:
The pharmacological study just presented has demonstrated the interesting inhibitory properties towards platelet aggregation of the compound Id and the absence of any activity of its isomer Il.
The medicine of the invention can be made available for oral administration in form of tablets, sugar-coated tablets, capsules, drops, granules, or a syrup. It can also be made available in the form of suppositories or for parenteral administration in the form of an injectable solution.
…
On account of its interesting inhibitory properties towards platelet aggregation and its interference in the mechanism of formation of arterial and venous thromboses, the medicine of the invention can be usefully administered in the treatment and prevention of platelet disorders due to extracorporeal blood circuits or the consequence of complications in artheroma.
[13] The patent concludes with 11 claims which can be summarized as follows:
- Claim 1 claims the dextro-rotatory isomer of methyl alpha-5 (4,5,6,7-tetrahydro (3,2-c) thieno pridyl) (2-chorophenyl)-acetate,
- Claims 2 to 5 claim salts of the compound in Claim 1,
- Claims 6 to 9 claim processes for preparation of the compound described in Claim 1,
-Claim 10 claims a pharmaceutical composition comprising an effective amount of the compound in Claim 1 in admixture with a pharmaceutically acceptable carrier, and
-Claim 11 claims a composition according to Claim 10 within a given dosage range.
THE DECISION UNDER APPEAL
[14] After disposing of a number of preliminary questions which are not in issue in this appeal, the Trial Judge addressed the construction of the patent. He first described the “inventive concept” of the patent, quoting the Supreme Court’s statement in Plavix:
78 In the present case, it is apparent that the inventive concept of the claims in the ‘777 patent is a compound useful in inhibiting platelet aggregation which has greater therapeutic effect and less toxicity than the other compounds of the ‘875 patent and the methods for obtaining that compound.
Plavix, at paragraph 78
[15] The Trial Judge then inquired into the relationship between the inventive concept and the invention itself. After a brief analysis relating to selection patents, the Trial Judge described the invention of the ‘777 Patent as follows:
…a compound which is useful in inhibiting platelet aggregation, has greater therapeutic effect and less toxicity than the other compounds of the ‘875 Patent, has the advantages of the salts (crystallize easily, not hygroscopic, and sufficiently water soluble) and the methods for obtaining that compound.
Reasons, at paragraph 140
[16] This led to the analysis of the promise of the patent. The Trial Judge identified the relationship between utility and the promise of the patent:
It is also worth recalling the role of the promise of the patent with respect to utility. On behalf of the Federal Court of Appeal, Justice Laydon-Stevenson in Ely Lilly Canada Inc., above, (FCA Olanzapine), at para 76, stated the following:
[76] Where the specification does not promise a specific result, no particular level of utility is required; a "mere scintilla" of utility will suffice. However, where the specification sets out an explicit "promise", utility will be measured against that promise: Consolboard ; Pfizer Canada Inc. v. Canada (Minister of Health), [2009] 1 F.C.R. 253, 2008 FCA 108 (Ranbaxy). The question is whether the invention does what the patent promises it will do.
Reasons, at paragraph 143 (my emphasis)
[17] After having reviewed the expert evidence, the Trial Judge framed the issue as whether the ‘777 Patent promises use in humans or merely potential use in humans. The Judge then considered the wording of the ‘777 Patent, including the references to “the medicine of the invention” and “pharmaceutical compositions”, as well as its relationship to the ‘875 Patent which explicitly referred to use in human and veterinary therapeutic applications. On the basis of this analysis, the Trial Judge concluded that:
In summary, the Court concludes that the POSITA [Person of Ordinary Skill in the Art] would find the promise respecting the use of the invention of the ‘777 Patent to be a use in humans.
Reasons, paragraph 175
[18] Having come to this conclusion, the Judge examined whether the utility of the invention had been demonstrated. His analysis of this question was based on a clopidogrel human study described as P-1062, a randomized double blind study comparing clopidogrel to a placebo in 10 healthy humans. This study is not referred to in the patent. The Judge found that the study was inconclusive as to the effectiveness of clopidogrel in humans. The Judge then considered whether one of the inventors of clopidogrel, Dr Daniel Fréhel, was aware of the activity of clopidogrel in humans prior the filing date. This issue turned on whether Dr. Fréhel was present at a meeting on January 28, 1988 at which time the therapeutic effect of clopidogrel in humans was discussed. The Trial Judge found the evidence on this point was also inconclusive. As a result, the Trial Judge found that the utility of clopidogrel in humans had not been demonstrated at the time of the patent application.
[19] The Judge then turned to the question of whether the inventors, as of the filing date, could soundly predict that the invention would be useful in humans. The Judge referred to the Supreme Court of Canada’s decision Apotex Inc. et al v Wellcome Foundation Ltd, 2002 SCC 77, [2002] 4 SCR 153 (AZT) at paragraph 70, where the elements necessary to support a finding of sound prediction are set out: (i) a factual basis, (ii) a sound line of reasoning, and (iii) disclosure of the first two elements.
[20] After a thorough review of the history leading to the filing of the application, including prior work on the ‘875 Patent, work on other compounds which had been abandoned, work on the racemate, (described as PCR 4099), as well as the circumstances leading to the decision to attempt to separate the enantiomers of the racemate, the Trial Judge found that there was both a factual basis for the sound prediction (paragraphs 404-488 of the Reasons) and an articulable line of reasoning leading to the sound prediction (paragraphs 489-583 of the Reasons).
[21] The Trial Judge then asked if these two elements were sufficiently disclosed in the patent specification. He concluded that they were not as “the ‘777 Patent does not instruct the POSITA that there was a factual basis and a line of reasoning for the prediction that the animal studies conducted on rat models could be extrapolated to the prediction that the compound - clopidogrel - had a use in humans”: see Reasons, at paragraph 570. In particular, the Judge found that the inventors’ “track record” in the development of clopidogrel was crucial to enable the POSITA “to make the leap to predict use of the compound in humans” and that it had not been disclosed.: see Reasons at paragraph 573. As a result, he found that the ‘777 Patent was “invalid for lack of sound prediction”: see Reasons, paragraph 585. To be more precise, the patent was invalid because the utility of the invention had neither been demonstrated nor soundly predicted as of the date of the filing of the patent application.
[22] Having found the patent to be invalid for lack of utility, the Trial Judge nonetheless went on to consider obviousness, the other ground of invalidity advanced by Apotex. He began by setting out the four step framework for the obviousness analysis set down by the Supreme Court in Plavix:
(1) (a) Identify the notional "person skilled in the art";
(b) Identify the relevant common general knowledge of that person;
(2) Identify the inventive concept of the claim in question or if that cannot readily be done, construe it;
(3) Identify what, if any, differences exist between the matter cited as forming part of the "state of the art" and the inventive concept of the claim or the claim as construed;
(4) Viewed without any knowledge of the alleged invention as claimed, do those differences constitute steps which would have been obvious to the person skilled in the art or do they require any degree of invention?
Plavix, cited above, at paragraph 67, quoted at Reasons, paragraph 589
[23] The Judge reiterated the Supreme Court’s teaching that the “obvious to try” test may be appropriate at the fourth step of the analysis, particularly in fields in which advances come as a result of experimentation.
[24] The Trial Judge identified the common general knowledge of the person skilled in the art. He then restated the inventive concept of the patent. The Trial Judge concluded that there was more disclosed in the ‘777 Patent than was in the common general knowledge: Reasons at paragraph 656. This then led to the last step in the analysis: was the invention simply the result of taking steps that were “obvious to try”?
[25] Since the claimed invention relates to the dextro-rotary isomer of a racemic mixture, the question which the Judge asked himself was whether it was obvious to separate the racemic mixture and thereby isolate the isomer which is the subject of the ‘777 Patent. The Trial Judge concluded that it was.
[26] The Judge’s conclusion focused on the racemic mixture identified in Sanofi’s laboratory documents as PCR 4099. That compound is one of approximately 250,000 compounds which come within the terms of the ‘875 Patent. The patent itself describes 21 specific examples of compounds coming within the terms of the patent, one of which is PCR 4099. The Judge found that there were, at the relevant time, two relevant known methods of separating racemic mixtures of the type described in the ‘875 Patent, and in particular, PCR 4099, though it was not self evident that either of them “ought to work”. In addition, he concluded that there was a well known and well established method of obtaining salts of the compounds resulting from such separation, including the isomers of PCR 4099.
[27] The Judge then asked whether there was a motive provided in the prior art to attempt to resolve compounds covered by the ‘875 Patent into their optical isomers. He identified factors which were known prior to the date of invention which would have led a person skilled in the art to separate the enantiomers of PCR 4099. Those factors were:
a- the “thalidoimide disaster” which sensitized regulators to the differential effects of isomers contained in a racemic mixture.
b- guidelines issued by Japanese regulators which “directed sponsors of applications for racemic drugs to separate and characterize the enantiomers”: Reasons, paragraph 727.
c- a speech given by senior official of the United States Food and Drug Administration (FDA) at the 1986 Annual Meeting of the American Pharmaceutical Association in which it was stated that sponsors of applications for racemic drugs would be expected to investigate the properties of the enantiomers of such racemic mixtures.
d- the adoption in 1987 by the FDA of guidelines relating to applications for racemic drugs and the establishment in 1989 of a stereoisomers committee by the FDA.
e- the awareness among leading chemists in the area of drug discovery that prior to 1989, there was already regulatory pressure toward separation of racemic mixtures.
[28] In summary, the Trial Judge found that, at the relevant time, the PCR 4099 compound, though not its properties was part of the common general knowledge and was featured in the ‘875 Patent, that the POSITA would have known of the method available to resolve PCR 4099 into its constituent enantiomers, that the methodology for salt selection was well known at that time, and that there was motivation to separate PCR 4099 into its enantiomers. He therefore found, on a balance of probabilities, that the “invention of the ‘777 Patent ‘was obvious to try’” so that the patent was invalid for obviousness: see Reasons at paragraph 784.
[29] At trial, the issue of infringement was a live issue as were certain defences to infringement raised by Apotex. Those conclusions were overtaken by the Trial Judge’s conclusions as to the validity of the ‘777 Patent. For the purposes of readability, I will deal with the analysis of the issues of validity and then deal with the issues of infringement separately.
ANALYSIS OF THE VALIDITY OF THE PATENT
Issues
[30] In my view, the critical issue with respect to utility arises from the Trial Judge’s construction of the ‘777 Patent. Did the Trial Judge err in reading into the patent an explicit promise that the invention could be used in humans?
[31] As to obviousness, the issue is whether the Trial Judge erred in holding that the invention was obvious based on the fact that the resolution of the racemate PCR 4099 was “obvious to try”?
Standard of review
[32] This is an appeal of a decision reached by a Trial Judge after a 26 day trial. The standard of review is that set out in Housen v. Nikolaisen, 2002 SCC 33, [2002] 2 S.C.R. 235 (Housen). Findings of fact are to be reviewed on a standard of palpable and overriding error: Housen, cited above, at paragraph 10. The Trial Judge’s conclusions on questions of law are subject to review on a standard of correctness: Housen, cited above, at paragraph 6. A question of mixed fact and law is also to be reviewed on a standard of palpable and overriding error unless the error involves an extricable error of law, in which case the standard of correctness applies.
[33] The construction of the patent is a question of law: Whirlpool Corp. v. Camco Inc., 2000 SCC 67, [2000] 2 S.C.R. 1067 (Whirlpool), at paragraph 76. The Trial Judge must interpret the patent as it would be understood by a person skilled in the art to which it pertains. This requires the judge to take into account the evidence as to how persons skilled in the art would understand certain words and phrases used in the patent, but it is for the judge to decide what the patent means: Consolboard Inc. v. MacMillan Bloedel (Saskatchewan) Ltd., [1981] 1 S.C.R. 504, (Consolboard) at pages 521-525.
Utility and the promise of the patent
[34] In Canadian law, patent law is purely statutory: Plavix at paragraphs 12, 13; Commissioner of Patent v. Fabwerks Hoechst Aktiengeselschaft Vormals Meister Lucius and Bruning (1963), [1964] S.C.R. 49. While the Courts have added to the fabric of patent law in Canada, the starting point for any analysis is the Patent Act R.S.C. 1985 c. P-4 (the Act), as it read at the material time. Since the application for the ‘777 Patent was filed in Canada on February 2, 1988, this dispute is governed by the terms of the Act as it read immediately before October 1, 1989 (the Old Act).
[35] The following two provisions of the Old Act are relevant to the issue of utility. The first is the definition of "invention":
“invention” means any new and useful art, process, machine, manufacture or composition of matter, or any new and useful improvement in any art, process, machine, manufacture or composition of matter;
(my emphasis)
« invention » Toute réalisation, tout procédé, toute machine, fabrication ou composition de matières, ainsi que tout perfectionnement de l’un d’eux, présentant le caractère de la nouveauté et de l’utilité.
(Je souligne)
[36] The second relevant statutory provision is s. 34(1) [now 27(3)] which read as follows at the material time:
34(1) An applicant shall in the specification of his invention
(a) correctly and fully describe the invention and its operation or use as contemplated by the inventor;
(b) set out clearly the various steps in a process, or the method of constructing, making, compounding or using a machine, manufacture or composition of matter, in such full, clear, concise and exact terms as to enable any person skilled in the art or science to which it appertains, or with which it is most closely connected, to make, construct, compound or use it;
(c) in the case of a machine, explain the principle thereof and the best mode in which he has contemplated the application of that principle;
(d) in the case of a process, explain the necessary sequence, if any, of the various steps, so as to distinguish the invention from other invention; and.
(e) particularly indicate and distinctly claim the part, improvement or combination that he claims as his invention
(2) The specification referred to in (1) shall end with a claim or claims stating distinctly and in explicit terms the things or combinations that the applicant regards as new and in which he claims an exclusive privilege or property is claimed.
34. (1) Dans le mémoire descriptif, le demandeur:
(a) décrit d’une façon exacte et complète l’invention et son application ou exploitation, telles que les a conçues l’inventeur;
(b) expose clairement les diverses phases d’un procédé, ou le mode de construction, de confection, de composition ou d’utilisation d’une machine, d’un objet manufacturé ou d’un composé de matières, dans des termes complets, clairs, concis et exacts qui permettent à toute personne versé dans l’art ou la science dont relève l’invention, ou dans l’art ou la science qui s’en rapproche le plus, de confectionner, construire, composer ou utiliser l’objet de l’invention;
(c) s’il s’agit d’un machine, en explique le principe et la meilleure manière dont il a conçu l’application de ce principe;:
(d) s’il s’agit d’un procédé, explique la suite nécessaire, le cas échéant, des diverses phases du procédé, de façon à distinguer l’invention d’autres inventions,
(e) indique particulièrement et revendique distinctement la partie, le perfectionnement ou la combinaison qu’il réclame comme son invention.
(2) Le mémoire descriptif se termine par une ou plusieurs revendications exposant distinctement et en termes explicites les choses ou combinaisons que le demandeur considère comme nouvelles et dont il revendique la propriété ou le privilège exclusif.
[37] These provisions are important because they frame the issue of what must be disclosed in the patent itself which, in turn, is relevant to the construction of the promise of the patent.
[38] Given the fact that an invention must be new and useful, must the demonstration of novelty and utility appear in the patent itself?
[39] In Consolboard, the Supreme Court considered this very question and held that an inventor need not describe the utility of his invention in his patent.
In my respectful opinion the Federal Court of Appeal erred also in holding that s. 36(1) requires distinct indication of the real utility of the invention in question.
....
Although (i) s. 36(1) [now s.27(3)] requires the inventor to indicate and distinctly claim the part, improvement or combination which he claims as his invention and (ii) to be patentable an invention must be something new and useful (s. 2), and not known or used by any other person before the applicant invented it (s. 28(1)(a)), I do not read the concluding words of s. 36(1) as obligating the inventor in his disclosure or claims to describe in what respect the invention is new or in what way it is useful. He must say what it is he claims to have invented. He is not obliged to extol the effect or advantage of his discovery, if he describes his invention so as to produce it.
Consolboard, cited above at pages 525, 526 (my emphasis)
[40] The Supreme Court of Canada has consistently followed this reasoning: see, e.g., Monsanto Canada Inc. v. Schmeiser, 2004 SCC 34, [2004] 1 S.C.R. 902, at paragraph 18; Whirlpool Corp. v. Camco Inc., 2000 SCC 67, [2000] 2 S.C.R. 1067, at paragraph 52 (Whirlpool); Pioneer Hi-Bred Ltd. v. Canada (Commissioner of Patents), [1989] 1 S.C.R. 1623, at page 1636 and, most recently, Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60, [2012] S.C.J. No. 60, at paragraphs 49-52.
[41] Are selection patents subject to the same rules? The nature of selection patents was explained Plavix, cited above, which makes frequent reference to the English case of In re I.G. Farbenindustrie A.G.’s Patents (1930), 47 R.P.C. 289 (Ch. D.) (I.G. Farbenindustrie):
At p. 321, he [Maugham J. the trial judge in I.G. Farbenindustrie] explained that in the field of chemical patents (which would of course include pharmaceutical compounds), there are often two "sharply divided classes". The first class of patents, which he called originating patents, are based on an originating invention, namely, the discovery of a new reaction or a new compound. The second class comprises patents based on a selection of compounds from those described in general terms and claimed in the originating patent. Maugham J. cautioned that the selected compounds cannot have been made before, or the selection patent "would fail for want of novelty". But if the selected compound is "novel" and "possess[es] a special property of an unexpected character", the required "inventive" step would be satisfied (p. 321). At p. 322, Maugham J. stated that a selection patent "does not in its nature differ from any other patent".
Plavix., cited above at paragraph 9 (my emphasis).
[42] Maugham J. specified that the “unexpected character” is “a substantial advantage to be secured or disadavantage to be avoided by the use of the selected members”: see I.G. Farbenindustrie, cited above, at pages 322, 323.
[43] The same concepts can be found in E. I. Du Pont de Nemours & Co. (Witsiepe's) Application, [1982] F.S.R. 303 (H.L.) where Lord Wilberforce stated, at page 311:
It is the absence of the discovery of the special advantages, as well as the fact of non-making, that makes it possible for such persons to make an invention related to a member of the class.
[44] In Plavix, cited above, the Supreme Court, at paragraph 11, accepted that a selection patent is like any other patent. As a result, it must satisfy the requirements of the Act, including the requirement that the invention be new and useful. The element of novelty is satisfied by the fact that the selected compounds have not previously been made. The element of utility is usually satisfied by the presence of a special property of an unexpected character, consisting in the advantage secured or the disadvantage avoided by the selection and which is at the heart of the inventive steps (Plavix above at paragarphs 9-10). Were it not so, no selection would meet the statutory criteria for patentability.
[45] A selection patent must also satisfy the disclosure requirements found in s. 34 of the Old Act. It does so by setting out in the specification “in clear terms the nature of the characteristic which the patentee alleges to be possessed by the selection for which he claims a monopoly”: see Plavix, at paragraph 114. See also Eli Lilly Canada Inc. v. Novopharm Ltd, 2010 FCA 197, [2012] 1 F.C.R. 349 (Olanzapine) at paragraph 78.
[46] A patent holder whose patent is challenged on grounds of lack of utility must be able to show that, at the time of the patent was applied for, the utility of the invention could either be demonstrated or soundly predicted: see AZT, at paragraph 46. The sticking point, in this case as in others, is to determine what it is that must be demonstrated or soundly predicted. This is where the notion of the promise of the patent comes into play.
[47] The promise of the patent is the standard against which the utility of the invention described in the patent is measured. The source of the concept is found in the decision of the Supreme Court of Canada in Consolboard:
There is a helpful discussion in Halsbury's Laws of England, (3rd ed.), vol. 29, at p. 59, on the meaning of "not useful" in patent law. It means "that the invention will not work, either in the sense that it will not operate at all or, more broadly, that it will not do what the specification promises that it will do".
Consolboard, cited above at p. 525
[48] While an inventor need not describe the utility of his invention in his patent, if he does so, he will be held to the promise which he has made. This was set out as follows in Olanzapine, cited above, at paragraph 76:
Where the specification does not promise a specific result, no particular level of utility is required; a "mere scintilla" of utility will suffice. However, where the specification sets out an explicit "promise", utility will be measured against that promise: Consolboard; Pfizer Canada Inc. v. Canada (Minister of Health), [2009] 1 F.C.R. 253, 2008 FCA 108 (Ranbaxy). The question is whether the invention does what the patent promises it will do.(emphasis in the original)
[49] If the inventor does not make an explicit promise of a specific result, the test for utility is a “mere scintilla” of utility. If, on the other hand, the inventor makes an explicit promise of a specific result, then utility will be assessed by reference to the terms of the explicit promise.
[50] When this Court said at paragraph 80 of Olanzapine, cited above, that the promise of the patent must be ascertained, it should not be taken to have assumed that every patent contains an explicit promise of a specific result since, subject to what is said below with respect to selection patents, there is no obligation on the part of the inventor to disclose the utility of his invention in the patent. In Olanzapine, the Court was simply indicating that the firs step in assessing utility was to determine the standard against which utility will be measured. This requires the Court to construe the patent to determine if a person skilled in the art would understand it to contain an explicit promise that the invention will achieve a specific result. If so, the inventor will be held to that promise. If there is no explicit promise of a specific result, then a mere scintilla of utility will do.
[51] In the case of selection patents, as we have seen, the novelty of the selection and its advantages (including disadvantages to be avoided) are the invention and must be described in the patent. The Trial Judge’s description of the invention is framed in terms of its advantages over the genus patent as was the Supreme Court’s description of the same invention in Plavix, cited above at paragraph 78. For ease of reference, I reproduce his description of the invention (Reasons at paragraph 140):
…a compound which is useful in inhibiting platelet aggregation, has greater therapeutic effect and less toxicity than the other compounds of the ‘875 Patent, has the advantages of the salts (crystallize easily, not hygroscopic, and sufficiently water soluble) and the methods for obtaining that compound.
[52] The Trial Judge turned his mind to whether the invention of the ‘777 Patent worked as described above. He examined toxicological tests in rats, mice and baboons, as well as studies of base activity, and concluded that the studies demonstrated the existence of the advantages which the inventors identified for the selection:
392 In terms of persuasive evidence given on this point, the Court notes that a Sanofi study (D-136, Tab-122 - SA361) demonstrated a differential LD50 and LD10 and that convulsions were a problem with PCR 4099 and the levo-rotatory enantiomer but not with clopidogrel. On this basis, it can be concluded that there was a differential toxicity as well as the better tolerability of clopidogrel.
395 On the basis of this evidence [the tests described at paragraph 394], the Court finds that Sanofi has demonstrated the differential toxicity as well as the better tolerability of clopidogrel.
399 Based on the evidence above, the Court accordingly finds that Sanofi has demonstrated the differential activity of clopidogrel.
Reasons, at paragraphs 392, 395, 399.
[53] Had the analysis ended here, the Trial Judge would have found that the compound of the ‘777 Patent had the advantages over the compounds of the ‘875 Patent which were described in the patent and whose existence had been demonstrated at the time of the filing of the application for the patent. To that extent, the promise of the patent had been met.
[54] An inventor whose invention is described in a patent which would otherwise be valid can nonetheless promise more for his invention than required by the Act so as to render his patent invalid. If he does so, so be it; it is a self-inflicted wound: see Free World Trust v. Électro Santé Inc., 2000 SCC 66, [2000] 2 S.C.R. 1024, at paragraph 51. But Courts should not strive to find ways to defeat otherwise valid patents. As the Supreme Court said in Consolboard, cited above, and reiterated some twenty years later in Whirlpool, cited above, at paragraph 49(g):
We must look to the whole of the disclosure and the claims to ascertain the nature of the invention and methods of its performance, (Noranda Mines Limited v. Minerals Separation North American Corporation ([1950] S.C.R. 36])being neither benevolent nor harsh, but rather seeking a construction which is reasonable and fair to both patentee and public. There is no occasion for being too astute or technical in the matter of objections to either title or specification for, as Duff C.J.C. said, giving the judgment of the Court in Western Electric Company, Incorporated, and Northern Electric Company v. Baldwin International Radio of Canada [[1934] S.C.R. 570], at p. 574, "where the language of the specification, upon a reasonable view of it, can be so read as to afford the inventor protection for that which he has actually in good faith invented, the court, as a rule, will endeavour to give effect to that construction". (my emphasis)
[55] While the construction of the patent is reserved to the Trial Judge, he is to read it and understand it as would the person skilled in the art. To that end, he has the evidence of experts as to how a person skilled in the art would understand the patent. In this case, only Apotex’s expert, Dr. Hirsh, a haemotologist, read the patent as promising that the invention would be effective in humans. Dr. Hirsh came to this conclusion on the basis of inferences which he drew from particular expressions used in the patent.
[56] Dr. Hirsh first noted that some of the diseases referred to in the patent are clearly human diseases and conditions (Expert Report of Dr. Hirsh (Confidential), Appeal Book, Tab 20 at paragraphs. 25, 68; Trial Transcripts, Vol. 2, Appeal Book, page 386, lignes 4, 5, 24-26; page 387, lines 1-5).
[57] Second, he noted that the high end of the daily dosage used to effect platelet aggregation was based on 10mg/kg, a dosage that would correspond with that needed by a human of average weight, approx. 50kg (Expert Report of Dr. Hirsh (Confidential), Appeal Book, Tab 20 at paragraph. 69).
[58] Third, the invention is described as being a “medicine and ‘active medicinal[s]’ for therapeutic purposes”. According to Dr. Hirsh, a haemotologist would understand from these words that this is a medecine that can be used in humans (Expert Report of Dr. Hirsh (Confidential), Appeal Book, Tab 20 at paragraph 68).
[59] Sanofi’s experts on the other hand recognized that the patent invites the person skilled in the art to understand that the invention has potential use in humans, but all expressed the view that the person skilled in the art would understand that no promise of a specific result is made in that regard.
[60] Dr. Byrn, a chemist said that:
“...any pharmaceutical chemist would interpret the ‘777 Patent as telling the world that very interesting results had been obtained and thus one might expect similar results would be achieved in humans but no clear promise or guarantee that such results would be achieved in humans.”
Reasons, at paragraph 150
[61] Dr. Rodricks, a toxicologist, testified to the effect that:
“the combination of platelet aggregating inhibiting activity and reduced toxicity...would suggest that the dextro-rotatory enantiomer holds promise as a useful human drug...however...the ‘777 Patent does not guarantee