Docket: A-191-16
Citation: 2017 FCA 76
|
CORAM:
|
PELLETIER J.A.
NEAR J.A.
RENNIE J.A.
|
|
BETWEEN:
|
|
BRISTOL-MYERS SQUIBB CANADA CO.,
BRISTOL-MYERS SQUIBB HOLDINGS IRELAND and NOVARTIS AG
|
|
Appellants
|
|
and
|
|
TEVA CANADA LIMITED
|
|
Respondent
|
|
and
|
|
THE MINISTER OF HEALTH
|
|
Respondent
|
REASONS FOR
JUDGMENT
PELLETIER J.A.
I.
INTRODUCTION
[1] In 1997, Novartis AG (then known as Ciba-Geigy Ltd.) filed a
Canadian patent application for a complex molecule known as atazanavir and its
pharmaceutically acceptable salts. It was granted Canadian Letters Patent No.
2,250,840 (the ‘840 patent) in 2006. Atazanavir’s potential as a treatment for
HIV (human immunodeficiency virus) and AIDS (acquired immunodeficiency
syndrome) is limited by its poor bioavailability. In 1998, Bristol-Myers Squibb
Canada Co. (BMS), having acquired rights to the atazanavir molecule, filed a
patent application for Type-I atazanavir bisulfate, a salt of atazanavir whose
superior bioavailability makes it useful in the formulation of an oral dosage
of atazanavir. BMS obtained Canadian Letters Patent No. 2,317,736 (the ‘736
patent) in 2004.
[2] In proceedings under the Patented Medicines (Notice of
Compliance) Regulations, SOR/93-133, the Federal Court found that Teva
Canada Limited’s (Teva) allegation that the ‘736 patent was invalid for obviousness
was justified and dismissed BMS’ application for a writ of prohibition. This is
an appeal from that decision.
[3] BMS argues that the Federal Court erred in its application of the “obvious to try” test set out in Apotex Inc. v.
Sanofi-Synthelabo Canada Inc., 2008 SCC 61, [2008] 3 S.C.R. 265, [Plavix
1] and applied by this Court in Sanofi-Aventis v. Apotex Inc., 2013
FCA 186, [2015] 2 F.C.R. 644 [Plavix 2]. Specifically, BMS argues that
the Federal Court erred in concluding that Teva’s allegation of obviousness was
justified in spite of the fact that it found that some of the properties of
Type-I atazanavir bisulfate were not predictable before it was made and tested.
[4] I come to the same conclusion as the Federal Court though for
somewhat different reasons. I would dismiss the appeal.
II.
THE DECISION UNDER APPEAL
[5] As these proceedings arise under the Patented Medicines (Notice
of Compliance) Regulations, the issue is whether Teva’s allegation of
obviousness in its Notice of Allegation has been shown to be justified. Any
question as to the validity of the ‘736 patent will have to be decided in an
action brought for that purpose.
[6] The Federal Court began its analysis on the issue of obviousness by
noting that the free base of atazanavir is not very soluble and that the person
skilled in the art [the Skilled Person] would know that one way of improving a
compound’s solubility and its bioavailability is to convert it to a salt using
a salt screen: Reasons at paras. 406-07. A salt screen is a process in which a
chemist uses various acids and solvents to produce salts of a compound.
[7] Different salts of a compound may have different properties when
compared to each other and when compared to the compound itself: Reasons at
para. 411. It was not contested that the Skilled Person would have expected a
salt screen to identify at least one salt with improved pharmaceutical
properties over the free base: Reasons at para. 412.
[8] The parties were agreed that the ‘840 patent disclosed the
atazanavir molecule and that salts of atazanavir could be made with a variety
of acids including sulfuric acid: Reasons at para. 408. However, the properties
of the resulting salts would not have been known prior to their being made:
Reasons at para. 411.
[9] The Federal Court then applied the framework for the analysis of
obviousness set out at paragraph 67 of Plavix 1.
[10] After
having identified the Skilled Person and the relevant common general knowledge,
the Federal Court turned to the inventive concept of the ‘736 patent. BMS argued
that the inventive concept of the ‘736 patent had four aspects: crystallinity,
oral bioavailability, stability and in situ transformation behaviour:
Reasons at para. 416. Teva’s evidence was that the inventive concept of the
patent was a pharmaceutical salt, Type-I atazanavir bisulfate and a
pharmaceutical formulation of Type-I atazanavir bisulfate. By way of
background, the ‘736 patent has only two claims, claim 1 which claims the
bisulfate salt of atazanavir and claim 2 which claims a pharmaceutical dosage
form comprising Type-I atazanavir bisulfate and a pharmaceutically acceptable
carrier. Teva argued, in effect, that the inventive concept was the compound
claimed in claims 1 and 2 of the ‘736 patent.
[11] The Federal
Court relied on paragraph 77 of Plavix 1 for the proposition that “where the inventive concept of the claims in a patent is not
readily discernable from the claims themselves (as may be the case with a bare
chemical formula), it is appropriate to read the specification in the patent to
determine the inventive concept of the claims”: Reasons at para. 421.
[12] The
Federal Court reviewed the disclosure of the ‘736 patent and the evidence of
each party’s experts and concluded at paragraph 446 that the inventive concept
of the ‘736 patent included:
i) the
improved oral bioavailability of Type-I atazanavir bisulfate over the free base
of atazanavir;
ii) the
anhydrous crystalline solid form of Type-I atazanavir bisulfate salts; and
iii) the
stability of Type-I atazanavir bisulfate salts.
[13] The
next step in the analysis is to identify the differences between the “state of the art” and the inventive concept. The
Federal Court disposed of this question by noting that none of the properties
found to be part of the inventive concept were disclosed in the prior art:
Reasons at para. 448.
[14] The
last step of the obviousness analysis asks whether the differences between the
prior art and the inventive concept represent steps that would have been
obvious to the Skilled Person, or whether those steps would have required any
inventiveness. The Federal Court began its analysis of this issue by inquiring
into the extent to which a Skilled Person has to be able to predict the
advantageous properties of a compound in order for the invention of that
compound to be obvious. This led to a review of the jurisprudence, in
particular the decisions in Plavix 1 and Plavix 2.
[15] Referring
to Plavix 1, the Federal Court noted, at paragraph 456, the Supreme
Court’s endorsement of the “obvious to try” test
and its comment that it might well be appropriate in areas such as the
pharmaceutical industry where advances are often won by experimentation: Plavix
1 at para. 68. The Federal Court then paraphrased paragraphs 65-66 of Plavix
1, stating that “to be ‘obvious to try’, there must
be evidence to convince a judge on a balance of probabilities that it was ‘very
plain’ or ‘more or less self-evident’ that what is being tested ought to work.
The mere possibility that something might turn up will not be enough”: Reasons
at para. 456.
[16] The
Federal Court next set out the non-exhaustive list of factors to be considered,
depending on the evidence in the case, when a court determines that the “obvious to try” test is appropriate. These factors
are set out at paragraph 69 of Plavix 1 as follows:
1. Is
it more or less self-evident that what is being tried ought to work? Are there
a finite number of identified predictable solutions known to persons skilled in
the art?
2. What
is the extent, nature and amount of effort required to achieve the invention? Are
routine trials carried out or is the experimentation prolonged and arduous,
such that the trials would not be considered routine?
3. Is
there a motive provided in the prior art to find the solution the patent
addresses?
[17] The
Federal Court then addressed this Court’s decision in Plavix 2, which
was cited to it as authority for the proposition that the lack of knowledge of
the properties of a compound meant that it was not obvious to try to obtain
that compound. BMS argued that the Skilled Person could not have predicted the
properties of the anhydrous form of atazanavir sulfate and therefore it was not
obvious to try to obtain a salt with those properties.
[18] The
Federal Court, however, considered Plavix 2 in the context of Plavix
1. It noted that in Plavix 1, the key factor on the question of
obviousness was the lack of knowledge of the properties of the enantiomers of
the compounds of the genus patent, including its racemate. While the technique
for resolving racemates was well known, having no knowledge of the properties
of the racemate meant that it was not possible to predict what the properties
of its enantiomers would be, therefore, it was not obvious to try to resolve the
racemate to obtain the enantiomer: Reasons at paras. 464-65; Plavix 2 at
paras. 73-75. BMS argued that this was precisely the case with respect to the
bisulfate salt of atazanavir.
[19] The
Federal Court pointed out an important difference between the facts in the Plavix
litigation and the present case. The Plavix litigation involved a selection
patent where the genus patent disclosed over 250,000 different compounds with
some utility in inhibiting platelet aggregation in blood. The genus patent
identified 21 specific examples of compounds coming within its scope, one of
which was a racemate known at PCR 4099. The Federal Court noted that the trial
judge in Plavix 2 found as a fact that the genus patent did not point
directly or indirectly to PCR 4099 so that the Skilled Person would have had no
motivation to focus on it over other compounds disclosed in the genus patent:
Reasons at para. 473.
[20] The
Federal Court concluded its comparison of Plavix 1 and Plavix 2
as follows:
I do not understand the finding of the
Federal Court of Appeal in Plavix #2 that, on the facts of that case, it
was not obvious to try to resolve the PCR 4099 racemate to stand for the
blanket proposition that in every case where a skilled person cannot predict
the properties of a compound in advance of making it, it will not be obvious to
try to obtain that compound.
Reasons at para. 475.
[21] The
balance of the Federal Court’s analysis consisted of applying the principles
derived from the jurisprudence to the facts of the case before it.
[22] While
there was a difference in the expert evidence on the point, the Federal Court
found that even though increasing solubility of a compound would not
necessarily increase its bioavailability, it would generally have that effect.
Thus the increase in bioavailability as a result of an increase in solubility
was more than a possibility and would have been more or less self-evident to
the Skilled Person: Reasons at para. 496.
[23] As
for the question of motivation to find the claimed solution, the Federal Court
found that the limited bioavailability of atazanavir would have given the
skilled person every reason to try to improve its solubility – and therefore its
bioavailability – by making its salts: Reasons at paras. 483, 497.
[24] After
reviewing the common general knowledge and known techniques for salt formation,
the Federal Court concluded that the Skilled Person would have come directly
and without difficulty to the bisulfate salts of atazanavir: Reasons at para.
501. The Court was confirmed in this view by the fact that BMS’ personnel
succeeded in making atazanavir salts, including Type-I atazanavir bisulfate
salt, on the very first day of their drug development project. Using routine
techniques, they were then able to characterize both Type-I and Type-II
atazanavir bisulfate salts insofar as solubility, crystallinity, melting
points, hygroscopicity and short term solid-state stability were concerned. The
Federal Court found that this process was neither prolonged nor arduous:
Reasons at para. 502. To the contrary, BMS’ personnel arrived at Type-I
atazanavir bisulfate “quickly, easily, directly and
relatively inexpensively”: Reasons at para. 503, citing Plavix 1
at para. 71.
[25] The
Federal Court concluded that, to the extent that the inventive concept of the
‘736 patent was the improved bioavailability of Type-I atazanavir bisulfate
salts over the free base of atazanavir, the invention was obvious: Reasons at
para. 505.
[26] As
for the other elements of the inventive concept, namely the anhydrous
non-hygroscopic crystalline solid form, and solid state stability of Type-I
atazanavir bisulfate, the Federal Court found that the discovery of these inherent
characteristics of Type-I atazanavir bisulfate salt added nothing to the “inventive work” of BMS’ personnel: Reasons at para.
507. To that extent, the determination that this salt had these characteristics
was a serendipitous discovery, made without prolonged or arduous work, and was
not an invention: Reasons at para. 508.
[27] As a
result, the Federal Court concluded that the invention of the Type-I atazanavir
bisulfate salt claimed in the ‘736 patent was obvious.
III.
Issues in the appeal
[28] BMS
challenges the Federal Court’s conclusion as to the obviousness of Type-I
atazanavir bisulfate salt on the basis of the Court’s failure to properly apply
the “obvious to try” test as set out by the
Supreme Court in Plavix 1. The substance of BMS’ argument is that the Court’s
finding that each of the elements of the inventive concept could not be
predicted is fatal to the finding of obviousness.
[29] This
argument is encapsulated in paragraphs 77-78 of BMS’ memorandum of fact and
law:
77. The ‘obvious to try’ test involves
a hypothetical cognitive exercise done before the claimed invention is made,
and without the benefit of hindsight. To use the words of the Supreme Court in Plavix
#1, it requires a finding, prospectively, that it would have been “more or
less self-evident to try to obtain the invention”.
78. To be satisfied in this case, the
legal standard requires the prospective finding (which was never made) that it
would have been more or less self-evident that a routine salt screen would
generate Type-I atazanavir bisulfate, and that it would have the properties the
Applications Judge found were included in the inventive concept.
(citations and emphasis omitted)
[30] Teva
counters this argument by pointing out that Plavix 1 does not stand for
the proposition for which it is cited and that this Court’s decision in Plavix
2 does not expand the scope of Plavix 1.
IV.
Analysis
[31] While
the proceeding below is in the form of an application for judicial review –
because it was brought by notice of application – it is in substance a summary
trial on affidavit evidence. No administrative action is being assessed against
a legal standard as would be the case in an application for judicial review. As
a result, I find that the appellate standard of review applies; correctness for
errors of law and palpable and overriding error for fact or mixed fact and law
(absent an extricable error of law): Agraira v. Canada (Public Safety and
Emergency Preparedness), 2013 SCC 36, [2013] 2 S.C.R. 559 at para. 45; Pharmascience
Inc. v. Canada (Health), 2014 FCA 133, 460 N.R. 343 at para. 31.
[32] The determinative
issue in this appeal is whether the Federal Court erred when it found that the development
of Type-I atazanavir bisulfate was obvious in spite of the fact that only one
of the three elements of the inventive concept, improved bioavailability over
the free base of atazanavir, was predictable and the uncontradicted evidence
was that the other two elements, crystallinity and stability, were not.
[33] The
basis for BMS’ argument is the Supreme Court’s decision in Plavix 1 and
this Court’s elaboration of its rationale in Plavix 2. It is therefore
useful to review those two cases to see if they support BMS’ position.
[34] The
innovative feature of the Supreme Court’s decision in Plavix 1 in
relation to obviousness was its adoption of the “obvious
to try” test, which it linked to the framework set out in jurisprudence
in the United Kingdom, namely Windsurfing International Inc. v. Tabur Marine
(Great Britain) Ltd., [1985] R.P.C. 59 (Eng. C.A.) [Windsurfing] and
Pozzoli SPA v. BDMO SA, [2007] EWCA Civ. 588, [2007] F.S.R. 37 [Pozzoli].
I will refer to this framework as the Windsurfing/Pozzoli framework.
[35] Prior
to Plavix 1, the leading case on obviousness was this Court’s decision
in Beloit Canada Ltd. v. Valmet OY (1986), 64 N.R. 287, 8 C.P.R. (3d)
289 at 294 (F.C.A.) [Beloit cited to C.P.R.] where the well-known
comparison to the “Man on the Clapham omnibus”
was drawn:
The classical touchstone for obviousness is
the technician skilled in the art but having no scintilla of inventiveness or
imagination; a paragon of deduction and dexterity, wholly devoid of intuition;
a triumph of the left hemisphere over the right. The question to be asked is
whether this mythical creature (the man in the Clapham omnibus of patent law)
would, in the light of the state of the art and of common general knowledge as
at the claimed date of invention, have come directly and without difficulty to
the solution taught by the patent.
[36] In Plavix
1, the Supreme Court addressed “the restrictiveness
with which the Beloit test has been interpreted in Canada”,
noting that the application judge had found that the Beloit test would
not accommodate the “worth a try” test: Plavix
1 at paras. 52. The Supreme Court reviewed the English and American
jurisprudence on the “obvious to try” test,
finding that it had been accepted in both jurisdictions. This convergence
influenced the Supreme Court in its decision to endorse the “obvious to try” test.
[37] The
Supreme Court then noted that the English jurisprudence identified the following
non-exhaustive list of factors as “useful guides in
deciding whether a particular step was ‘obvious to try’” (Plavix 1
at para. 59):
The question of obviousness must be
considered on the facts of each case. The court must consider the weight to be
attached to any particular factor in the light of all the relevant
circumstances. These may include such matters as the motive to find a solution
to the problem the patent addresses, the number and extent of the possible
avenues of research, the effort involved in pursuing them and the expectation
of success.
H. Lundbeck A/S v. Generics (UK) Ltd., [2008] EWCA Civ. 311, [2008] R.P.C. 19 at paras. 24-25 [Lundbeck],
citing Angiotech Pharmaceuticals Inc. v. Conor Medsystems Inc., [2007]
EWCA Civ. 5, [2007] R.P.C. 20 at para. 45, rev’d on other grounds [2008] UKHL
49, [2008] R.P.C. 28.
[38] Having
noted these factors, the Supreme Court was quick to add that “the ‘obvious to try’ test must be approached cautiously”
because it “is only one factor to assist in the
obviousness inquiry”: Plavix 1 at para. 64.
[39] After
a brief digression into the meaning of “obvious”,
the Supreme Court offered its view as to the threshold for the “obvious to try” test:
For a finding that an invention was “obvious
to try”, there must be evidence to convince a judge on a balance of
probabilities that it was more or less self-evident to try to obtain the
invention. Mere possibility that something might turn up is not enough.
Plavix 1 at
para. 66.
[40] This
led the Court to the next step in its reasoning, which was to say that it would
be useful in an obviousness inquiry “to follow the
four-step approach first outlined by Oliver L.J.” in Windsurfing as updated in Pozzoli, [i.e. the Windsurfing/Pozzoli
framework], reproduced below:
(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 1 at
para. 67.
[41] The
Supreme Court then stated that “[i]t will be at the
fourth step of the Windsurfing/Pozzoli approach to obviousness that the
issue of ‘obvious to try’ will arise”: Plavix 1 at para. 67.
[42] The
Supreme Court, immediately following its articulation of the Windsurfing/Pozzoli
framework, asked when the “obvious to try” test
might be appropriate. Its discussion of this question is reproduced below:
In areas of endeavour where advances are often
won by experimentation, an “obvious to try” test might be appropriate.
In such areas, there may be numerous interrelated variables with which to
experiment. For example, some inventions in the pharmaceutical industry might
warrant an “obvious to try” test since there may be many chemically similar
structures that can elicit different biological responses and offer the
potential for significant therapeutic advances.
Plavix 1 at
para. 68 (my emphasis).
[43] The
contingency that the “obvious to try” test might
not apply in any given case is underlined at the next step of the Supreme
Court’s reasoning, where it identifies the factors that should be
considered if an “obvious to try” test is
warranted. The Court then rephrased the non-exhaustive list of factors set out
in Lundbeck [the Lundbeck factors] that apply in accordance with
the evidence in a given case:
1. Is
it more or less self-evident that what is being tried ought to work? Are there
a finite number of identified predictable solutions known to persons skilled in
the art?
2. What
is the extent, nature and amount of effort required to achieve the invention?
Are routine trials carried out or is the experimentation prolonged and arduous,
such that the trials would not be considered routine?
3. Is
there a motive provided in the prior art to find the solution the patent
addresses?
Plavix 1 at
para. 69.
[44] The
Court suggested another factor which, it seems to me, is essentially an
elaboration of the second factor. After pointing out that “obviousness is largely concerned with how a skilled worker
would have acted in the light of the prior art”, the Court commented
that this was “no reason to exclude evidence of the
history of the invention, particularly where the knowledge of those involved in
finding the invention is no lower than what would be expected of the skilled
person”: Plavix 1 at para. 70. If the inventors, operating at the
same level as a Skilled Person, came to the invention quickly and easily in
light of the prior art and the common general knowledge, this would suggest
that a Skilled Person would have acted in much the same way and come to the
same conclusion: Plavix 1 at para. 71.
[45] Having
set out the applicable principles, the Supreme Court undertook the “obvious to try” analysis at first instance. The trial
judge had not done so and the Supreme Court considered it preferable to avoid
remitting the matter to the trial judge for redetermination so as to avoid
further delay: Plavix 1 at para. 73.
[46] The
first two elements of the Windsurfing/Pozzoli framework, the
identification of the person skilled in the art and the common general
knowledge, were straightforward. The person skilled in the art was a trained
pharmachemist and the common general knowledge included the fact that that
there were five well-known methods to separate the relevant racemate, PC 4099,
into its isomers but did not include the relative advantages of the
dextro-rotatory isomer: Plavix 1 at paras. 74-75.
[47] The
identification of the inventive concept was also straightforward. The Supreme
Court construed the claims of the ‘777 patent as constituting “the dextro-rotatory isomer of the racemate and its
pharmaceutically acceptable salts and processes for obtaining them”: Plavix
1 at para. 76. The inventive concept was not readily discernable from the
claims, thus the Supreme Court construed it as “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 1 at
paras. 77-78.
[48] In
the third step the Supreme Court departed from the Windsurfing/Pozzoli
framework which calls for the identification of the differences between the
common general knowledge and the inventive concept. Instead, the Supreme Court
compared the ‘875 patent (the genus patent) to the ‘777 patent (the selection
patent). It concluded that, unlike the ‘875 patent, the ‘777 patent disclosed “that the invention of the dextro-rotatory isomer of
the racemate, clopidogrel, and its bisulfate salt discloses their beneficial
properties over the levo-rotatory isomer and the racemate and expressly
describes how to separate the racemate into its isomers”: Plavix 1 at paras. 79-80.
[49] This
took the Supreme Court to the fourth and final step of the Windsurfing/Pozzoli
framework, inquiring whether the differences between the common general
knowledge and the inventive concept would have been obvious to the Skilled
Person. The Supreme Court first asked if recourse to the “obvious to try” test was warranted. Referring to the
expert evidence as to the discovery of the beneficial properties of the
dextro-rotatory isomer and its bisulfate salts, it concluded that recourse to
the “obvious to try” test was warranted and that
the application judge had erred in not applying the “obvious
to try” test: Plavix 1 at paras. 81-82.
[50] Applying
the “obvious to try” factors, the Supreme Court
first asked whether it was self-evident that what was being tried ought to
work. It noted that the Skilled Person would not know, before isolating and
testing them, that the properties of the dextro-rotatory isomer would be
different from the properties of the racemate or the levo-rotatory isomer:
Reasons at paras. 84-85. The focus on the properties of the isomers was
dictated by the fact that it is the special properties of the selection which
make it inventive.
[51] The
Court went on to find that the mere fact that there were well know techniques
for isolating isomers did not mean that it was evident to apply those
techniques, even if it was known that the properties of the isomers and the
racemate might be different: Plavix 1 at para. 85.
[52] Turning
to the “extent, nature and amount of effort required to
achieve the invention”, the Supreme Court noted that it would have small
significance in light of the Court’s observations on the actual course of
conduct leading to the invention. When considering the latter factor, the
Supreme Court observed that Sanofi had spent several millions of dollars to
develop the racemate in issue – not its isomers – for several years, to the
point of testing it in its salified form in clinical trials, before attempting
to see if the dextro-rotary isomer had advantageous properties compared to the
racemate. If it had been obvious to separate the racemate and test the
properties of the dextro-rotary isomer, the Court reasoned that Sanofi would
not have wasted the time and money it did in attempting to commercialize the
racemate: Plavix 1 at paras. 91-92.
[53] The
Court found that while it could be assumed that there was a general motive to
find an effective and non-toxic product to inhibit platelet aggregation, there
was nothing in the ‘875 patent or common general knowledge to motivate the
Skilled Person to pursue the invention of the ‘777 patent: Plavix 1 at
para. 90.
[54] The
Supreme Court summarized its conclusions on obviousness as follows:
…it was not self-evident from the '875
patent or common general knowledge what the properties of the dextro-rotatory
isomer of this racemate would be or what the bisulfate salt's beneficial
properties would be and therefore that what was being tried ought to work. The
course of conduct and the time involved throughout demonstrate that the
advantage of the dextro-rotatory isomer was not quickly or easily predictable.
Had the dextro-rotatory isomer been “obvious to try”, it is difficult to
believe that Sanofi would not have opted for it before unnecessary time and
investment were spent on the racemate. I conclude that the prior art and
common general knowledge of persons skilled in the art at the relevant time
were not sufficient for it to be more or less self-evident to try to find the
dextro-rotatory isomer.
Plavix 1 at
para. 92 (my emphasis).
[55] BMS
did not limit its argument to Plavix 1 but also relied on this Court’s
decision in Plavix 2. It is worth underlining what this Court decided on
the issue of obviousness in Plavix 2:
Given that the Trial Judge applied the test
for obviousness set out in Plavix [Plavix 1], and given that he
applied it to the same material facts as the Supreme Court, he ought to have
come to the same conclusion.
Plavix 2 at
para. 81.
[56] Having
said that the trial judge in Plavix 2 erred in coming to a different
conclusion than did the Supreme Court in Plavix 1 when he applied the
same law to the same facts, this Court was hardly in a position to argue that
some other test should have been applied. I am therefore of the view that one
should be wary of seeing things in Plavix 2 that have no foundation in Plavix
1. The governing authority remains Plavix 1. I also agree with the
distinction which the Federal Court drew between the facts of Plavix 1
and the facts of this case.
[57] It
is useful, at this point, to take stock and to review what Plavix 1
teaches and what it leaves for the lower courts to work out.
[58] As
noted earlier, the novel feature of Plavix 1 is its endorsement of the “obvious to try” test which it linked to the Windsurfing/Pozzoli
framework. The impetus for this endorsement was the “acontextual”
application of the Beloit test to all classes of claims. It noted that “the courts have often tended to treat the word formulation
of Beloit as if it were a statutory prescription that limits the obviousness
inquiry”: Plavix 1 at para. 61. Along the same lines, it
expressed its view that in matters where courts must make factual
determinations, rigid rules are inappropriate unless mandated by statute.
[59] At
the same time, the Supreme Court showed itself to be very cautious about
substituting one rigid rule for another. Its discussion leading to its endorsement
of the “obvious to try” test is replete with
cautionary notes, including the observation that the “obvious
to try” test is not mandatory in England and the United States: Plavix
1 at para. 62. It made the point that the “obvious
to try” test was to be approached cautiously as it was only one factor
in the obviousness inquiry, from which one might conclude that it is not
mandatory in Canada either: Plavix 1 at para. 64. After having set out
the Windsurfing/Pozzoli framework, the Court asked when the “obviousness to try” test might be appropriate, which
suggests that it might not always be appropriate. The Supreme Court went on to conclude
that it might be so in pharmaceutical litigation. In introducing the Lundbeck
factors, the Supreme Court was careful to stipulate that those factors should
be considered if the “obvious to try”
test was warranted. In applying the Windsurfing/Pozzoli framework to the
case before it, the Supreme Court began its consideration of the last step by
asking “whether the nature of the invention in this
case is such as to warrant an ‘obvious to try’ test”: Plavix 1 at
para. 81.
[60] The
reasonable conclusion to be drawn from these expressions of caution is that the
“obvious to try” test has not displaced all
other inquiries into obviousness. Indeed, that is what this Court concluded in Wenzel
Downhole Tools Ltd. v. National-Oilwell Canada Ltd., 2012 FCA 333, [2014] 2
F.C.R. 459 at para. 105. In a passage referring to the adoption of the “obvious to try test”, this Court wrote:
Finally, one must recall that the Supreme
Court of Canada in Sanofi clearly indicated that there is no single or
mandatory approach in the obviousness inquiry. Indeed, accepting that the
“obvious to try” approach might be useful depending on the circumstances was part
of a move away from rigid rules that had limited the obviousness inquiry,
towards a more flexible, expansive, and fact driven inquiry (Sanofi at
paragraphs 61-63). The Court only wanted to bring more structure, clarity, and
objectivity to the analysis (Sanofi at paragraph 67).
(See also, in a pharmaceutical context, Teva
Canada Ltd. v. Novartis Pharmaceuticals Canada Inc., 2013 FCA 244, 451 N.R.
246 at para. 7.)
[61] While
the Supreme Court accepted the “obvious to try”
test as a way of addressing the issue of obviousness, other inquiries remain
possible, including the Beloit test, subject to the Court’s warnings
about a rigid “acontextual” application of that
test, or of any other for that matter. The Court has made it clear that it favours
“an expansive and flexible approach that would include
‘any secondary considerations that [will] prove instructive’”: Plavix
1 at para. 63.
[62] As a
result, I am of the view that a categorical approach to obviousness, such as
that advocated by BMS, is inappropriate. The elaboration of a hard and fast
rule that obviousness cannot be shown unless all the elements of the inventive
concept can be predicted with a high degree of certainty is the antithesis of
the approach to obviousness that the Supreme Court favoured in Plavix 1.
Not every case requires recourse to the “obvious to
try” test and not every recourse to the “obvious
to try” test must follow in the furrow of the preceding application of
that test.
[63] The
caution with which the Supreme Court approached the “obvious
to try” test might be contrasted with the manner in which it adopted the
Windsurfing/Pozzoli framework. There was no discussion of the reasons
why the Supreme Court felt that it would be useful to adopt that framework
beyond its conclusory statement that it “should bring
better structure to the obviousness inquiry and more objectivity and clarity to
the analysis”: Plavix 1 at para. 67. Nor did the Supreme Court
refer to the cautionary note struck in Pozzoli with respect to the
inventive concept:
In some cases the parties cannot agree on
what the concept is. If one is not careful such a disagreement can develop into
an unnecessary satellite debate. In the end what matters is/are the
difference(s) between what is claimed and the prior art. It is those
differences which form the "step" to be considered at stage (4). So
if a disagreement about the inventive concept of a claim starts getting too
involved, the sensible way to proceed is to forget it and simply to work on the
features of the claim.
Pozzoli at
para. 19 (my emphasis).
[64] It
is true that the Windsurfing/Pozzoli framework does provide structure but
it is not obvious that it has been useful. In Allergan Inc. v. Canada
(Minister of Health), 2012 FC 767, 103 C.P.R. (4th) 155 at paras. 135-141,
Hughes J. quickly surveyed some of the varying interpretations of the inventive
concept which have emerged since 2008. A more comprehensive survey is found in
Joshua Sealy-Harrington, “The Inventive Concept in
Patent Law: Not So Obvious” (2015) 27 I.P.J. 385 at 394-409.
[65] It
may be helpful to keep in mind that the obviousness analysis asks whether the
distance between two points in the development of the art can be bridged by the
Skilled Person using only the common general knowledge available to such a
person. If so, it is obvious. The first of those points is the state of the
prior art at the relevant date. References in the jurisprudence to “the inventive concept”, “the
solution taught by the patent”, “what is
claimed” or simply “the invention” are
attempts to define the second point.
[66] Prior
to Plavix 1, the jurisprudence followed Beloit and treated the
second point as “the solution taught by the patent”
which was often treated as synonymous with “what is
claimed in the patent” or “the invention”:
Proctor & Gamble Pharmaceuticals Canada Inc. v. Canada (Minister of
Health), 2004 FCA 393, [2005] 2 F.C.R. 269 at para. 47, Pfizer Canada
Inc. v. Canada (Health), 2007 FCA 209, 366 N.R. 347 at para. 133, Novopharm
Limited v. Janssen-Ortho Inc., 2007 FCA 217, 366 N.R. 290 at para. 25. The
question is whether the “inventive concept” was
intended to redefine the second point as it was understood to be prior to Plavix
1. I note that in the passage from Pozzoli quoted above, the English
Court of Appeal did not consider the “inventive
concept” to have changed anything of substance. If the parties could not
agree on it, it could be forgotten. It went on to say at paragraph 19 of its
reasons: “In the end what matters is/are the
difference(s) between what is claimed and the prior art.” This is essentially
the state of Canadian law prior to Plavix 1.
[67] Is
it the case that changing one of the two points I referred to earlier amounts
to changing the definition of obviousness? Given that obviousness is concerned
with whether bridging the difference between the prior art and a second point
requires inventiveness, changing the second point will affect the difficulty of
bridging that difference, therefore making inventiveness more or less likely.
If that is so, is it reasonable to conclude that the Supreme Court intended to
change the definition of the obviousness analysis when it adopted, without
commentary, the Windsurfing/Pozzoli framework? Is it likely that the
Supreme Court, having taken great care in modifying the test for
obviousness, would, without saying so, change the definition of obviousness?
[68] My
inclination is to believe that the Supreme Court does not change substantive law
by implication, particularly when it has shown a cautious approach to change in
the same context: see Apotex Inc. v. Eli Lilly Canada Inc., 2016 FCA 267,
142 C.P.R. (4th) 171 at para. 37.
[69] As
an aside, it seems to me that the use of “inventive
concept” begs the question which the Windsurfing/Pozzoli
framework seeks to answer. The question in an obviousness inquiry is whether
there has been inventiveness or not. Requiring the Court to identify the
inventive concept assumes inventiveness. It is illogical to ask the Court to
identify the inventive concept of the claimed invention and then to ask it to
determine if the claimed invention is in fact inventive.
[70] In
my view, this is the conundrum which the Federal Court faced in this case.
Having identified the inventive step as comprising three elements, the Federal
Court was forced to say at the conclusion of its analysis that two of those
elements were not inventive at all. It is this conclusion which feeds the
present appeal. I would say, in light of the Federal Court’s reasoning, that its
error was not in its application of the “obvious to
try” test but in its identification of the inventive concept.
[71] All
of this brings me to the merits of this appeal.
[72] The
first steps of the Windsurfing/Pozzoli framework are not contentious. The
Federal Court’s correctly identified the person skilled in the art and the
common general knowledge. In particular, I note the conclusion at paragraph 412
of the Federal Court’s reasons that the Skilled Person would have expected that
a salt screen would likely identify at least one salt that would have improved
pharmaceutical properties compared to the free base of atazanavir.
[73] The
relevant prior art is the teaching of the ‘840 patent which teaches atazanavir
and claims it and its pharmaceutically acceptable salts.
[74] The
key issue was the identification of the inventive concept. In my view, the
Federal Court erred in its identification of the inventive concept. The source
of its error was its failure to articulate the meaning of the inventive
concept. On the basis of the arguments made to it by the parties, the Federal
Court implicitly adopted a definition of the inventive concept which focussed
on the properties of atazanavir bisulfate. This was, in my view, an extricable
error of law that justifies our intervention.
[75] For
the reasons set out above, I find that the “inventive
concept” is not materially different from “the
solution taught by the patent”. Had the Federal Court applied that
definition to the facts, it would have found that the inventive concept in this
case is atazanavir bisulfate, a salt of atazanavir which is pharmaceutically
acceptable because it has equal or better bioavailability than the atazanavir
free base. Atazanavir’s limited bioavailability was the source of the
motivation to pursue the solution. The fact that claim 2 of the ‘736 patent
claims a pharmaceutical dosage form of Type-I atazanavir bisulfate confirms its
acceptability for pharmaceutical purposes.
[76] Had
the Federal Court correctly defined the inventive concept, it would have found,
at step 3 of the Windsurfer/Pozzoli framework, that there is no
difference between the prior art and the inventive concept or the solution taught
by the patent. This is to say that there is no difference between (i) atazanavir
and its pharmaceutically acceptable salts and (ii) atazanavir bisulfate, a salt
of atazanavir which is pharmaceutically acceptable because of its
bioavailability. In any event, such difference as there was between the two
could be bridged, at step 4 of the Windsurfing/Pozzoli framework,
without inventiveness using only the common general knowledge of the person
skilled in the art. The Skilled Person would have expected that a salt screen
would likely identify at least one salt that would have improved pharmaceutical
properties, specifically bioavailability, compared to the free base of
atazanavir: Reasons at paras. 412, 495. Furthermore, it was only a matter of
routine work to characterize the properties of such a salt: Reasons at paras.
400, 504.
[77] On
that basis, if the Federal Court had correctly defined the inventive concept,
it would not have found it necessary to apply the “obvious
to try” test. However, if it were necessary to apply that test, its
consideration of the second Lundbeck factor, at paras. 501-504 of its
reasons was a sufficient ground upon which to find that Teva’s allegation of
obviousness was justified.
[78] It
will be recalled that the second Lundbeck factor is the extent, nature
and amount of effort required to achieve the invention. In essence, this
inquiry is very similar to the Beloit inquiry as to whether, having
regard to the prior art and the common general knowledge, the Skilled Person
would come directly and without difficulty to the claimed invention. The
Federal Court found that the extent, nature and amount of effort required to
get to Type-I atazanavir bisulfate showed that its discovery was obvious:
Reasons at paras. 502-503.
[79] It
will be recalled that the ‘840 patent claimed atazanavir and its pharmaceutically
acceptable salts: Reasons at para. 381. It will also be recalled that the
experts were agreed that conducting salt screens were routinely used when
attempting to increase the solubility of a compound. Increasing a compound’s
solubility will generally increase its bioavailability: Reasons at para. 496. In
addition, the ‘840 patent identified sulfuric acid as one of the acids which
might be used to make an atazanavir salt: Reasons para. 408.
[80] The
Federal Court reviewed the course of BMS’ development work resulting in the
isolation of Type-I atazanavir bisulfate as a candidate for patentability. BMS
scientists succeeded in making Type-I atazanavir bisulfate salts, among others,
on the first day of their drug development process. It took approximately six
weeks to characterize Type-I and Type-II salts insofar as their various
properties were concerned, but this work was routine and not arduous: Reasons
at paras.399-400, 504. There was no suggestion that BMS scientists were working
at a higher level than would have been persons skilled in the art: Reasons at
para. 503. On this evidence, the Federal Court was entitled to conclude that a
skilled person “would quickly, easily, directly and
relatively inexpensively, in light of the prior art and common general
knowledge” come to Type-I atazanavir bisulfate salt. In the Federal
Court’s view, the discovery of Type-I atazanavir bisulfate was obvious: Reasons
at paras. 509-10. I agree.
[81] In
addition, the Federal Court concluded that there was motivation to find a
pharmaceutically acceptable salt of atazanavir with superior bioavailability
than the free base of atazanavir, the third Lundbeck factor: Reasons at
paras. 481-84. Though not necessarily a sufficient ground for finding that the
development of atazanavir bisulfate was obvious, this factor confirms the
conclusion to which the Federal Court came in considering the second Lundbeck
factor.
[82] On
the facts of this case, it seems to me that the facts which support the
conclusion that the distance between the prior art and the inventive concept
(defined as the solution taught by the patent) could be bridged without
recourse to inventiveness would also satisfy the first Lundbeck factor
in that it was more or less self-evident that what was being tried ought to
work. It seems to me that when this factor is taken it was articulated by the
Supreme Court, the conclusion that the Skilled Person would have regarded a
salt screen as a more or less self-evident way of getting to a form of
atazanavir with greater bioavailability is inescapable.
[83] In
the result, I would dismiss the appeal because, having regard to the prior art
and the common general knowledge of the Skilled Person, the development of atazanavir
was obvious.
V.
CONCLUSION
[84] I
would therefore dismiss the appeal with costs.
"J.D. Denis Pelletier"
“I agree
D.G. Near
J.A.”
“I agree
Donald J. Rennie
J.A.”
Email this Content