Date: 20080320
Docket: A-79-07
Citation: 2008 FCA 108
CORAM: LINDEN J.A.
NADON
J.A.
RYER
J.A.
BETWEEN:
PFIZER CANADA INC.
and WARNER-LAMBERT COMPANY, LLC
Appellants
and
THE MINISTER OF HEALTH
and RANBAXY LABORATORIES LIMITED
Respondents
REASONS FOR JUDGMENT
NADON J.
INTRODUCTION:
[1]
This is an
appeal from an Order of von Finckenstein J. of the Federal Court, 2007 FC 91,
dated January 25, 2007, dismissing the application of Pfizer Canada Inc. and
Warner-Lambert Company, LLC (collectively “Pfizer”) made pursuant to section 6
of the Patented Medicines (Notice of Compliance) Regulations,
S.O.R./93-133, for an Order prohibiting the Minister of Health from issuing a
Notice of Compliance (“NOC”) to Ranbaxy Laboratories Limited (“Ranbaxy”) with
respect to atorvastatin calcium until after the expiration of Canada Letters Patent
No 2,021,546 (the “546 patent”).
[2]
Pfizer
asks this Court to set aside the Order of von Finkenstein J. and to issue a
prohibition order, with costs on the appeal and the application.
THE FACTS
[3]
U.S.
Patent 4,681,893 (the “893 patent”) and its equivalent Canadian Letters Patent
No. 1,268,768 (the “768 patent”) cover a large class of cholesterol-lowering
compounds called statins, which decrease the production of cholesterol in the
human body by inhibiting HMG-CoA reductase, an enzyme involved in the biosynthesis
of cholesterol.
[4]
On April
29, 1997, the 546 patent was issued to Warner-Lambert Company, a predecessor of
the appellant Warner-Lambert Company, LLC. The patent has a filing date of July
19, 1990 and a publication date of January 22, 1991. It expires on July 19,
2010.
[5]
The 546
patent claims a selection of the compounds covered by the 893 and 768 patents.
It contains 12 claims directed at the lactone, dihydroxy-acid and five
pharmaceutically acceptable salts of atorvastatin.
[6]
Atorvastatin
is an enantiomer. Enantiomers are molecules having the same chemical structure
but differing in terms of the three-dimensional arrangements of their atoms.
Each enantiomer is the non-superimposable mirror image of the other enantiomer.
A racemic mixture or racemate is a 50/50 mixture of the two enantiomers of a
molecule. Although enantiomers have the same physical, chemical and spectral
properties, their biological properties are often different. In general, one
enantiomer is biologically active while the other is inactive. As a result, the
active enantiomer is generally two times more active than the racemate.
[7]
The 546
and 768 patents are listed with respect to atorvastatin calcium 10 mg, 20mg,
40mg and 80 mg tablets (the calcium salt of atorvastatin) and marketed by Pfizer
under the trade name LIPITOR.
[8]
Ranbaxy
filed an Abbreviated New Drug Submission (“ANDS”) with the Minister, seeking a
NOC for its drug product RAN-ATORVASTATIN, comparing it to LIPITOR for the
purposes of demonstrating bioequivalence. In its ANDS, Ranbaxy referenced the 546
and the 768 patents, as required to by the Regulations.
[9]
On January
31, 2005, Ranbaxy sent a Notice of Allegation (“NOA”) to Pfizer, alleging that
in making, using and selling its product, it would not infringe the 768 patent
and that the 546 patent was invalid for obviousness, double patenting,
insufficiency and anticipation.
[10]
Pfizer
responded to Ranbaxy’s NOA by filing a Notice of Application on March 17, 2005,
disputing the allegations found in the NOA and arguing that they were not
justified.
THE DECISION BELOW
[11]
On January
25, 2007, von Finkenstein J. dismissed Pfizer’s prohibition application. First,
he found that the allegation of non-infringement with respect to the 768 patent
was not justified. That finding was not appealed by Ranbaxy. Second, with
respect to the 546 patent, the Judge concluded that the patent was invalid
because it did not meet the requirements of subsection 27(3) of the Patent
Act, R.S.C. 1985, c. P-4 (the “Act”).
[12]
The Applications
Judge began his examination of the allegations made against the 546 patent by
construing claim 6 of the patent which claims the calcium salt of atorvastatin.
Although claim 6 is the only claim at issue in these proceedings, claims 1, 2
and 6 are relevant and they read as follows:
Claim 1:
[R-(R*,R*)]-2-(4-fluorophenyl)-[β],[δ]-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenylamino)-cabonyl]-1H</u>pyrrole-1-heptanoic
acid or (2R-trans)-5-(4-fluorophenyl)-2-(1-methylethyl-N,4-diphen
yl-1-[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide;
and pharmaceutically acceptable salts thereof.
Claim 2:
A compound of Claim 1
which is
[R-(R*,R*)]-2-(4-fluorophenyl)-[β],[δ]-dihydroxy-5-((1-methylethyl)-3-phenyl-4-[(phenylamino)-cabonyl]-1H</u>pyrrole-1-heptanoic
acid.
Claim 6:
The hemicalcium salt of
the compound of Claim 2.
[13]
In Pfizer
Canada Inc. v. Canada (Minister of Health), 2006 FC 1471 (“Novopharm”)
von Finkenstein J. was similarly called upon to construe claim 6 of the 546
patent. In that case, he simplified the relevant claims in the following manner
(at paragraph 35):
Fortunately,
these complex formulae have been given simpler names such that Claims 1, 2 and
6 can be read more easily as follows:
Claim 1: Atorvastatin
acid or atorvastatin lactone; and pharmaceutically acceptable salts thereof;
Claim 2: Atorvastatin
acid.
Claim 6: The hemicalcium
salt of the compound of Claim 2.
[14]
He then
construed claim 6 as follows (at paragraph 44):
Upon reading
the patent, and taking into account the expert advice so as to read through the
eyes of a person skilled in the art, the Court reads the disclosure as
explaining the following:
-- atorvastatin in its
lactone form, its corresponding ring-opened acid form, and the pharmaceutically
acceptable salts thereof is useful for lowering cholesterol levels in mammals,
including humans.
-- atorvastatin in its
lactone form, its corresponding ring-opened acid form, and its pharmaceutically
acceptable salts thereof provides an unexpected and surprising inhibition of
cholesterol biosynthesis; unexpected in that it is a ten-fold increase over the
inhibition provided by the racemic mixture. The data for this ten-fold
increase comes from a CSI screen disclosed in the 893 Patent. All compounds for
the CSI screen were prepared as described in the 893 Patent.
-- the most preferred
embodiment of the invention described in the 546 Patent is the hemicalcium salt
of the atorvastatin acid.
-- the compounds of the
lactone form, the corresponding ring-opened acid form, and the pharmaceutically
acceptable salts thereof all have generally equivalent utility.
[Emphasis
added]
[15]
As von
Finkenstein J. did not see any material difference between the evidence of the
experts before him in Novopharm, above, and of those before him in the
present matter, he accordingly adopted the same construction as in Novopharm
(paragraph 62). Pursuant to that construction, the 546 patent promises a
ten-fold increase in activity for atorvastatin in comparison to the racemic
mixture. The calcium salt of atorvastatin is the preferred embodiment of the
invention.
[16]
After
construing claim 6 of the 546 patent, the Judge turned to the allegation made
by Ranbaxy in its NOA that the 546 patent did not fully and correctly describe
the invention, contrary to subsection 27(3) of the Act. He therefore examined
the data that Pfizer had obtained through two types of assays.
[17]
The first
type of assay is the Cholesterol Synthesis Inhibition (CSI) screen. It is an in
vitro assay which measures the effect of a test compound on the entire cholesterol
biosynthesis pathway. The ability of the compound to inhibit the reaction is
expressed as the IC50 value, which represents the amount of
test compound required to inhibit cholesterol biosynthesis by 50%. The lower
the IC50, the more potent the compound.
[18]
The second
type of assay is the Acute Inhibition of Cholesterol Synthesis (AICS) assay. It
is an in vivo assay which measures the extent to which a test compound
or its metabolites are absorbed, transported and ultimately active in the liver
to inhibit cholesterol biosynthesis.
1. CSI Data
[19]
The 546
patent refers to a single set of CSI data to support the claim of increased
activity for atorvastatin in comparison to the racemate. The Applications Judge
was of the view that the data could not be relied upon to support a claim of
ten-fold increase in inhibition for two reasons. First, the data refers to the
sodium salt of atorvastatin and not the calcium salt. It is therefore not
possible to draw conclusions from one salt to another. Second, the alleged
ten-fold increase is based on an averaging of data for the racemic salt
collected across five different experiments. The averaging of CSI results for
the atorvastatin racemate does not provide a scientifically meaningful result.
[20]
Before the
Applications Judge, Pfizer presented the results from the CSI 118 assay, which
compares the calcium salt of atorvastatin to the racemic salt of atorvastatin.
The Applications Judge found that the data could not be relied upon because the
test compound was not completely dissolved in the stock solution. Without
knowing the concentration of the test compound in the solution, it was not
possible to quantify the results of the assay.
2. AICS Data
[21]
Although
the AICS data was not referred to in the 546 patent to support an increase in
activity for atorvastatin, the applications judge nevertheless considered the
data. It was a head-to-head comparison of the racemic calcium salt of
atorvastatin against the calcium salt of atorvastatin. According to the Applications
Judge, the AICS data was a reliable indicator of the inherent ability of
atorvastatin calcium or its racemate to inhibit cholesterol synthesis. The data
revealed an increase in activity for the calcium salt of atorvastatin that was
only slightly more that two-fold that of the racemic salt of atorvastatin.
[22]
According
to the Applications Judge, the data did not substantiate the promise of a ten-fold
increase in activity and, as a result, he concluded that the disclosure of the 546
patent was insufficient as it failed to comply with the requirements of
subsection 27(3) of the Act:
[122]
While these cases undoubtedly set the bar for section 27(3) very low, Pfizer in
this case has not vaulted over that low bar. In essence, the 546 Patent makes
two assertions, one as to activity the other as to the preferred salt. The
first assertion is that there is an unexpected and surprising inhibition of
cholesterol biosynthesis because of the ten-fold increase in activity between
atorvastatin calcium and the racemic calcium salt. However, from the
evidence presented, this statement is incorrect. The only reliable data
available, the AICS data, suggests an increase in activity barely over the
expected two-fold when the racemate is resolved into its individual
enantiomers. This is not anywhere close to ten-fold.
[123] I fail to
see how this amounts to ‘correctly and fully describing the invention’. A
patentee has an obligation to make truthful statements regarding the nature of
the invention in the disclosure of the patent. This principle was
discussed by Harold G. Fox in “The Canadian Law and Practice Relating to
Letters Patent for Inventions”, 4th ed. (Toronto: Carswell 1969) at 188:
If a word is used
inaccurately, but the nature of its use appears sufficiently from the context,
the patent will be good. Nor will a specification be construed as invalid if it
possesses only small errors and inaccuracies that are in the nature of clerical
errors, or amount only to such as the ordinary workman will recognize and
correct. This rule does not apply, however, unless the errors and inaccuracies
appear on the face of the specification. If they only appear after further
experimentation, or if they amount to a false suggestion, even though
immediately perceivable by the ordinary skilled workman, the specification will
be insufficient. The patentee cannot rely on the skill and knowledge of the
addressee to correct errors or false promises that he has inserted in the
specification.
[124]
Here we clearly have an assertion of a ten-fold increased activity on the
face of the specification. This false suggestion of a ten-fold increase in
activity cannot be backed up by the data provided. Accordingly, I find the
546 Patent to be invalid for failing to meet the requirements of s. 27(3) of
the Patent Act
[Emphasis
added]
[23]
Before the
applications judge, Ranbaxy also claimed that the 546 patent did not identify
the physical properties of atorvastatin calcium that support the claim that it
is the preferred embodiment of the invention, nor was there any data to support
such a claim. Having found that the assertion of a ten-fold increase in
activity was not correct, the applications judge did not find it necessary to
test the assertion that the calcium salt of atorvastatin was the preferred embodiment
of the invention.
[24]
As the
Applications Judge found that Pfizer did not prove that the allegation of
insufficiency was unjustified, he did not consider the other allegations of
invalidity raised by Ranbaxy in its NOA.
THE RELEVANT
LEGISLATION
[25]
Subsection
27(3) of the Act reads as follows:
|
(3)
The specification of an invention must
(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 pertains, 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 of the machine and the best mode in which the inventor has
contemplated the application of that principle; and
(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 inventions.
|
(3) Le
mémoire descriptif doit :
a) décrire d’une façon exacte et complète
l’invention et son application ou exploitation, telles que les a conçues son
inventeur;
b) exposer 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 versée 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’invention;
c) s’il s’agit d’une machine, en expliquer
clairement le principe et la meilleure manière dont son inventeur en a conçu
l’application;
d) s’il s’agit d’un procédé, expliquer la suite
nécessaire, le cas échéant, des diverses phases du procédé, de façon à
distinguer l’invention en cause d’autres inventions.
|
THE ISSUES
[26]
This
appeal raises the following issues:
1.
What is
the applicable standard of review?
2.
Did the
Applications Judge err in dismissing the application for insufficiency?
3.
Are the
allegations of invalidity for obviousness, anticipation or double patenting
justified?
PFIZER’S SUBMISSIONS
[27]
Pfizer
submits that the Applications Judge made the following errors:
1.
He
erroneously construed section 27(3) of the Act and ignored Supreme Court of
Canada jurisprudence according to which a patent need not “describe in what
respect the invention is new or in what way it is useful”.
2.
He
misconstrued the teaching and promise of the patent. The patent promises that
the enantiomer atorvastatin possesses a surprising and unexpected superior
activity over the racemic mixture in inhibiting the synthesis of cholesterol.
It does not promise a specific amount of increased activity. Although the
patent includes data from the CSI assay which shows a ten-fold increase in
activity, the CSI assay is an in vitro assay. There is no promise that in
vivo atorvastatin calcium will have this level of increase in activity.
3.
He erred
in rejecting the CSI data, particularly the data from the CSI 118 assay, as
being unreliable. The CSI 118 assay was the best data as it was the only head-to-head
experiment comparing atorvastatin calcium to its corresponding racemic mixture
and opposite enantiomer. This assay illustrates an approximate ten-fold
increase in activity over its racemate in vitro. The applications judge
should not have dismissed the data on the basis that a uniform suspension of
the compound in the stock solution was not obtained. Pfizer’s method did not
require complete dissolution of the test compound. Ranbaxy did not provide the
Court with any data to disprove the results of the CSI 118 or to contradict
surprising and unexpected activity of atorvastatin, despite the fact that
Ranbaxy had conducted its own tests.
4.
He erred
in relying on the AICS data. AICS is not a reliable indicator of the inherent
or intrinsic potency of atorvastatin. It is an in vivo experiment which
measures the bioavailability of a compound. Even if the AICS data could be
relied upon, it shows the surprising activity of the calcium salt of
atorvastatin versus its racemate. Whereas only a two-fold increase in activity
could be expected, the AICS results revealed almost a three-fold increase in
activity.
5.
He failed
to properly assess the expert evidence. His role was to weigh the evidence and
make findings of fact. He failed to explain why he favoured the evidence of
Ranbaxy’s expert witnesses.
6.
His
findings are inconsistent with those made in the Novopharm, supra,
proceedings where he held that the 546 patent was a valid selection patent with
surprising and unexpected advantages over the class from which it was selected.
There is no material difference between the evidence in that case and in this
case.
[28]
Pfizer
also submits that the other grounds of invalidity raised by Ranbaxy in its NOA
are unjustified.
RANBAXY’S SUBMISSIONS
[29]
Ranbaxy
disagree with Pfizer’s position and argues that the Applications Judge did not
err in finding that the allegation of invalidity for insufficiency was
justified.
1.
He applied
the correct legal test when considering the law of insufficiency.
2.
He made no
error in finding that the 546 patent promises that atorvastatin is ten-fold
more active than its racemate.
3.
He made no
error in finding that the data before him did not support the promise of a
ten-fold increase in activity.
4.
He made no
error in concluding that the 546 patent was insufficient on the basis that the
promised ten-fold advantage did not exist.
5.
His
decision is not inconsistent with his earlier ruling in the Novopharm, supra,
proceedings. There were marked differences between the records in the two
cases.
[30]
Ranbaxy
further submits that the other allegations of invalidity set out in the NOA are
justified.
ANALYSIS
1. What is the applicable
standard of review?
[31]
The
characterization of the applicable legal test is a question of law, reviewable
on the correctness standard: Housen v. Nikolaisen, [2002] 2 S.C.R. 235.
The construction of a patent is also a question of law reviewable on the same
standard: Whirlpool v. Camco, [2000] 2 S.C.R. 1067 at paragraph 76.
2. Did the Applications Judge
err in dismissing the application for insufficiency?
[32]
For the
reasons that follow, I conclude that the Applications Judge was incorrect in
dismissing Pfizer’s application on the basis of insufficiency. He
mischaracterized the scope of the disclosure requirement under subsection 27(3)
of the Act and, in so doing, allowed Ranbaxy to attack, through an alternative
means, the patent’s utility, novelty and/or obviousness. His reasoning is
inconsistent with the purpose of subsection 27(3).
(A) Disclosure
requirement under the Act
[33]
Subsection
27(3) of the Act provides that the specification of an invention (which
includes both the disclosure and the claims in the patent) must:
(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 pertains, 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 of the machine and the best mode in
which the inventor has contemplated the application of that principle; and
(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 inventions.
(i) Purpose
of subsection 27(3):
[34]
The
disclosure requirement under the Act lies at the heart of the whole patent
system: see Consolboard Inv. v. MacMillan Bloedel (Saskatchewan) Ltd.,
[1981] 1 S.C.R. 504 at 517; Pioneer Hi Bred Ltd. v. Canada (Commissioner of Patents), [1989] 1 S.C.R. 1623 at
paragraph 23. The granting of a patent is akin to a contract between the Crown
and the inventor in which the latter receives an exclusive right to exploit his
invention for a certain period in exchange for complete disclosure to the
public of the invention and the way in which it operates: see Pioneer Hi
Bred, supra, at paragraph 23. The description of the invention is therefore
the quid pro quo for which the inventor is given a monopoly for a
limited term of years on the invention: see Consolboard, supra, at 517.
The Supreme Court has referred with approval (for example, in Consolboard,
supra, at 517; in Pioneer Hi Bred, supra, at paragraph 23) to the
following passage by Harold G. Fox in Canadian Patent Law and Practice,
4th ed. (1969) at p. 163:
The
consideration for the grant is double: first, there must be a new and useful
invention, and secondly, the inventor must, in return for the grant of a
patent, give to the public an adequate description of the invention with
sufficiently complete and accurate details as will enable a workman, skilled in
the art to which the invention relates, to construct or use that invention when
the period of the monopoly has expired. The function of the description
contained in the specification is both to enable the construction and use of
the devices contained therein after the expiry of the patent, and also to
enable others to ascertain with some measure of exactness the boundaries of the
exclusive privilege upon which they may not trespass during the exercise of the
grant.
[Emphasis
added]
(ii) Scope
of subsection 27(3):
[35]
In Pioneer
Hi Bred, supra, at paragraph 27, the Supreme Court of Canada explained the
scope of subsection 27(3) as follows:
The applicant must
disclose everything that is essential for the invention to function properly.
To be complete, it must meet two conditions: it must describe the invention and
define the way it is produced or built (Thorson P. in Minerals Separation North
American Corp. v. Noranda Mines Ltd., [1947] Ex. C.R. 306,
at p. 316). The applicant must define the nature of the invention and describe
how it is put into operation. A failure to meet the first condition would
invalidate the application for ambiguity, while a failure to meet the second
invalidates it for insufficiency. The description must be such as to enable a
person skilled in the art or the field of the invention to produce it using
only the instructions contained in the disclosure (Pigeon J. in Burton Parsons
Chemicals Inc. v. Hewlett-Packard (Canada) Ltd., [1976] 1 S.C.R. 555,
at p. 563; Monsanto Co. v. Commissioner of Patents, [1979] 2 S.C.R. 1108,
at p. 1113) and once the monopoly period is over, to use the invention as
successfully as the inventor could at the time of his application (Minerals
Separation, supra, at p. 316).
[36]
In Hughes
and Woodley on Patents, 2nd ed., Volume 1, at 333, the authors
describe the requirement that a disclosure be sufficient as follows:
Insufficiency
is directed to whether the specification is sufficient to enable a person
skilled in the art to understand how the subject matter of the patent is to be
made […] An allegation of insufficiency is a technical attack that should not
operate to defeat a patent for a meritorious invention; such attack will
succeed where a person skilled in the art could not put the invention into
practice.
[Emphasis
added]
[37]
Subsection
27(3) of the Act does not require that a patentee explain how well his
invention works in comparison to other inventions. He is not required to
describe in what respect his invention is new or useful, nor is he obliged to
“extol the effect or advantage of his discovery, if he describes his invention
so as to produce it”: see Consolboard, supra, at 526.
(iii) Selection
patents:
[38]
The law
with respect to selection patents was explained by this Court in Pfizer
Canada Inc. v. Canada (Minister of Health), 2006 FCA 214, where, at
paragraphs 3 to 5, Malone J.A. stated:
[3]
There are two general classes of chemical patents. The first is the
'originating patent' where there is an originating invention involving the
discovery of a new reaction or a new compound. The second is the 'selection patent',
which is based on a selection from related compounds derived from the original
compound and which have been described in general terms and claimed in the
originating patent (see In the Matter of I.G. Farbenindustrie A.G.'s Patents,
(1930) 47 R.P.C. 283 at page 321 per Maugham J.).
[4]
While there is little Canadian jurisprudence on the subject of selection
patents, its elements are well defined in I.G. Farbenindustrie. Lord
Diplock cited this decision with approval in the House of Lords where he stated
that the 'inventive step in a selection patent lies in the discovery that
one or more members of a previously known class of products possess some
special advantage for a particular purpose which could not be predicted before
the discovery was made' (see Beecham Group Ltd. v. Bristol Laboratories
International S.A. [1978] R.P.C. 521 at page 579). All claimed members of
the known class must have the advantage and the advantage must not be one that
those skilled in the art would expect to find in a large number of the
previously disclosed class (i.e. a quality of special character) (see I.G.
Farbenindustrie at page 323).
[5]
Selection patents exist to encourage researchers to further use their inventive
skills so as to discover new advantages for compounds within the known class. A
selection patent can be claimed for a selection from a class of thousands or
for a selection of one out of two (see for example I.G. Farbenindustrie
at page 323 and E.I. Dupont de Nemours & Co (Witsiepse's) Application,[1982]
F.S.R. 303 (H.L) at page 310).
[Emphasis
added]
[39]
In Beecham
Group, supra, at 579, Lord Diplock stated, in respect of selection patents,
that “the quid pro quo for the monopoly granted to the inventor is the
public disclosure by him in his specification of the special
advantages that the selected members of the class possess” [Emphasis
added]. This passage has been cited with approval by the Federal Court on a
number of occasions: see Pfizer Canada Inc. v. Canada (Minister of Health), 2006 FC 1471, at paragraph
49; Sanofi-Synthelabo Canada Inc. v. Apotex Inc., 2005 FC 390, at
paragraph 56.
[40]
Furthermore,
in Patent Law of Canada (Gordon F. Henderson ed., Carswell Legal
Publications, 1994), the learned authors write at page 211-212:
When the
invention consists of the selection of one or more members of a previously
known group, based upon the discovery that the selected members have a
previously unknown advantage over the others, the advantage must be
disclosed in the specification in order to make full disclosure of the
invention. As in other cases, however, what is claimed is not the advantage
but the selected members. …
[Emphasis
added]
[41]
Subsection
11.12 of the current edition of the Manual of Patent Office Practice has
this to say on the topic of selection patents:
A selection
from members of a previously known class of substances may be patentable if the
substance selected is unobvious and affords a new and useful result. There must
be a special advantage arising from the selected substances and any
advantage, novel property or use must be fully characterized in the description.
The substance should be defined in an explicit manner within the claim.
[Emphasis
added]
[42]
The above
passages suggest that the disclosure requirement may be a bit more onerous for
selection patents. This Court has considered selection patents in only two
cases. It did not, however, in either case, suggest that a higher level of
disclosure was required: see Pfizer Canada Inc. v. Canada (Minister of Health), 2006 FCA 214; Sanofi-Synthelabo
Canada Inc. v. Apotex Inc, 2006 FCA 421.
[43]
In the
present matter, von Finkenstein J. did not characterize the 546 patent as a
selection patent. However, in the Novopharm, supra, proceedings, he did
find that the 546 patent was a valid selection patent (at paragraph 96).
Although the Novopharm decision was appealed and the case was heard by
this Court, the parties settled the matter before a decision was rendered.
[44]
In these
proceedings, Pfizer asserts that the 546 patent is a selection patent. Ranbaxy,
on the other hand, takes an entirely different view. At paragraph 13 of its
Memorandum, it states:
… Pfizer
argues that claim 6 of the 546 Patent is a selection from the genus of
compounds claimed in the 893 Patent. In making this argument, Pfizer disregards
that the 893 Patent specifically claims, in claim 5, the lactone version of the
racemate of atorvastatin.
[45]
Ranbaxy’s
argument seems to be that the 546 patent is not a selection patent since it
claims compounds covered by another patent. This position disregards the fact
that selecting a narrow class of compounds covered by a genus patent is the
very nature of the selection patent. Ranbaxy itself refers to the 546 patent as
a selection later on its Memorandum, at paragraph 72:
… Where an
inventor has purported to make a selection based on a special advantage, the
inventor must describe the special advantage that makes the invention novel
over the prior art.
[46]
In my
opinion, there can be no doubt that the 546 patent is a selection patent. It
covers the lactone, acid and pharmaceutically acceptable salts of atorvastatin,
one of the many compounds covered by the 768 and 893 patents. The basis for the
patent is that the compounds claimed therein display a special advantage,
namely the surprising and unexpected inhibition of cholesterol biosynthesis,
i.e. greater than twofold. The calcium salt of atorvastatin, the compound
specifically covered by claim 6, is the preferred embodiment of the invention:
see 546 patent, Appeal Book, Volume 1, page 91.
(B) Disclosure in the
546 patent
[47]
The
paragraphs of the 546 patent which are relevant to the promise of an increase
in inhibition of cholesterol biosynthesis for atorvastatin read as follows:
BACKGROUND OF THE INVENTION
[…]
Trans-([plus
or
minus])-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide
are among compounds of U,S. Patent No. 4,681,893 having usefulness as
inhibitors of cholesterol biosynthesis. The compounds therein broadly
include 4-hydroxypyran-2-ones and the corresponding ring-opened acids derived
therefrom.
It is now
unexpectedly found that the enantiomer having the R form of
the ring-opened acid of trans-5-(4-fluorophenyl)-2-(1-methylethyl)-N,4-diphenyl-1-[2-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-1H-pyrrole-3-carboxamide;
that is [R-(R*,R*)]-2-(4-fluorophenyl)-β,
δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[phenyl amino)carbonyl]-1H-pyrrole-1-heptanoic
acid, provides surprising inhibition of the biosynthesis of cholesterol
(Appeal Book, Volume 1, p. 91).
[…]
However, an
ordinarily skilled artisan may not predict the unexpected and surprising
inhibition of cholesterol biosynthesis of the present invention in view of the
disclosures in the prior art [Appeal Book, Volume 1, p. 92).
[…]
DETAILED DESCRIPTION OF THE INVENTION
[…]
The compounds
according to the present invention and especially according to the compound of
the formula I inhibit the biosynthesis of cholesterol as found in the CSI
screen that is disclosed in U.S. Patent No.
4,681,893. The CSI data of the compound I, its enantiomer the
compound II and the racemate of these two compounds are as follows:
|
COMPOUND
[R-(R*R*)] isomer
[S-(R*R*)]isomer
Racemate
|
IC50(micromoles/liter)
0.0044
0.44
0.045
|
Accordingly,
the present invention is the pharmaceutical composition prepared from the
compound of the formula I or II or pharmaceutically acceptable salts thereof.
These
compounds are prepared as described in U.S. Patent No. 4,681,893 (Appeal Book,
Volume 1, p. 99).
[Emphasis
added]
[48]
As to salt
selection, the disclosure of the 546 patent provides:
Appropriate
pharmaceutically acceptable salts within the scope of the invention are those
derived from bases such as sodium hydroxide, potassium hydroxide, lithium
hydroxide, calcium hydroxide, 1-deoxy-2(Methylamino)-D-glucitol, magnesium
hydroxide, zinc hydroxide, aluminium hydroxide, ferrous or ferric hydroxide,
ammonium hydroxide or organic amines such as N-methylglucamine, choline,
arginine and the like. Preferably, the lithium, calcium, magnesium, aluminium
and ferrous or ferric salts are prepared from the sodium or potassium salt by
adding the appropriate reagent to a solution of the sodium or potassium salt,
i.e., addition of calcium chloride to a solution of the sodium or potassium
salt of the compound of the formula I will give the calcium salt thereof.
[…]
The most
preferred embodiment of the present invention is [R-(R*R*)]-2-(4-fluorophenyl)-ß,
δ-dihydroxy-5-(1-methylethyl)-3-phenyl-4-[(phenyl
amino)carbonyl]-1H-pyrrole-1-heptanoic acid, hemicalcium salt (Appeal
Book, Volume 1, page 95)
[Emphasis
added]
(C) Allegations of insufficiency
in the NOA
[49]
In its
NOA, Ranbaxy alleges that “the 546 patent is invalid on the basis of
insufficient support” (Appeal Book, Volume 1, page 234). The relevant passages
appear at pages 20 and 21 of the NOA (Appeal Book, Volume 1, pages 243 and
244):
The
disclosure of the 546 patent is not sufficient to correctly or fully describe
the invention being claimed contrary to ss. 27(3) and 34(1) of the Patent
Act, R.S.C. 1985, c. P-4 as amended. The disclosure does not support
there being any novel or inventive aspect as claimed.
The background
in the 546 patent asserts at page 1, lines 14 to 22 that “it is now
unexpectedly found that the enantiomer having the R form of the ring-opened
acid of the [lactone]; that is [atorvastatin acid], provides surprising
inhibition of the biosynthesis of cholesterol.
The only
support for the allegation that the described invention has surprising and
unexpected properties is a single set of CSI data allegedly relating to
the effectiveness of each of the two trans-enantiomers and the trans-racemate
shown at page 8, lines 12 to 16, as follows:
|
COMPOUND
[R-(R*R*)] isomer
[S-(R*R*)]isomer
Racemate
|
IC50(micromoles/liter)
0.0044
0.44
0.045
|
Evidence
presented in the U.S. trial, held at the end of 2004 in Delaware on the
corresponding U.S. patent (5,273,995), by Dr. Scallen, showed that the above
table is not representative of all the data collected by Pfizer, and
also showed that the CSI experiments were not conducted properly.
Ranbaxy relies on the non-confidential transcript of the evidence given by Dr.
Scallen at the U.S. trial of Pfizer, Inc., et al, v. Ranbaxy
Laboratories et al., Court File number 03-209-JJF, on December 3, 2004.
Dr. Scallen
testified that the test results included in the 546 patent were limited to a
non-representative, incomplete selection of in vitro CSI experiments.
Specifically, Dr. Scallen testified that when all, or any, representative
selection of the CSI experiments conducted by Pfizer are considered, the data
as a whole showed tremendous variability, cannot draw scientifically valid conclusions
from the data as a whole. In the words of Dr. Scallen, “one can’t do
science under those circumstances”.
Moreover, as
explained Dr. Scallen, Pfizer has conducted more reliable in vitro
AICS experiments which were not included in the 546 Patent. Dr. Scallen
testified that these ACIS experiments showed an approximately two-fold
difference between the racemate and the R-(R*R*) enantiomer. Dr. Scallen
testified that his conclusions on the AICS data with conclusions drawn by
Pfizer, in internal memoranda, after review of the same data. Dr. Scallen
testified that his conclusions were consistent with the conclusions drawn by
Pfizer that, as expected, the atorvastatin calcium is twofold more potent that
the racemic calcium salt which contains 40% inactive isomer.
Ranbaxy also
notes that Pfizer did not call the Pfizer employee who conducted the AICS tests
to testify at trial. That employee concluded, based on the two in vivo
experiments, that the R-(R*R*) enantiomer was only twice as active as the
racemate, and that the result was not surprising and unexpected.
The inventor
has access to all CSI, COR and AICS data and apparently chose only
unrepresentative parts of that data to support the alleged “surprising”
activity of the R enantiomer.
[Emphasis
added]
[50]
Ranbaxy
challenges the promise made by Pfizer in the 546 patent that atorvastatin
displays unexpected and surprising increase in activity over the racemate. It
does so by attacking the reliability of the data that underlies this promise.
More specifically, Ranbaxy claims that the only support for the allegation that
the described invention has surprising and unexpected properties is a single
set of CSI data which is not representative of all the data collected by Pfizer
through CSI experiments. The CSI data as a whole showed tremendous variability
and was not reliable. The data obtained by Pfizer from AICS experiments, which
was not included in the 546 patent, was more reliable and revealed only a
two-fold difference between atorvastatin and its racemate.
[51]
These
allegations, although placed under a heading entitled “sufficiency” in the NOA,
have, in my respectful view, nothing to do with the disclosure requirement
under subsection 27(3) of the Act. Rather, they are relevant to an analysis of
the utility, novelty and/or obviousness of a patent. This is clear from the
first paragraph of the NOA cited above, according to which “[t]he disclosure
does not support there being any novel or inventive aspect as claimed”. What
Ranbaxy is really challenging in its NOA under the heading of “sufficiency” is
the fact that Pfizer obtained a selection patent without having provided
reliable data showing that the narrow class of compounds selected was better
than the compounds covered by the genus patent.
(D) Errors of the Applications
Judge
[52]
In my
view, the Applications Judge erred in two respects. First, he erred in
construing the 546 patent as promising a ten-fold increase in activity for
atorvastatin as compared to its racemate. Second, he erred in focusing his
subsection 27(3) analysis on whether the data substantiates the promise made by
the patent.
(i) Construction
of the patent:
[53]
The
decision in American Cyanamid v. Ethicon Limited, [1979] R.P.C. 215 at
261 (Ch.D.) stands for the proposition that although a patentee is not
obligated to promise a result in the patent, if he does make such a promise, he
will be held to it.
[54]
The
Applications Judge was incorrect in construing the 546 patent as promising a
ten-fold increase in activity for atorvastatin as opposed to the racemate.
Rather, the promise is that the compounds covered have an “unexpected and
surprising inhibition of biosynthesis of cholesterol”, i.e. greater than
twofold (Appeal Book, Volume 1, page 92). Although the 546 patent goes on to
refer to CSI data set out in a table in support of this promise, in my opinion,
the data is merely illustrative of the magnitude of this promise in vitro.
[55]
Because a
patent is notionally addressed to a person skilled in the art, its claims must
be construed purposively, through the eyes of a person skilled in the art: see Whirlpool,
supra, at paragraph 49; and Consolboard, supra, at 521. A person
skilled in the art will be interested in whether the compounds claimed by the 546
patent have increased activity in vivo. They will know that CSI data,
which represents the activity of a compound in vitro, does not reflect
the activity of the compound in vivo. They will not read the patent as
promising the exact increase in activity that is set out in the CSI data table.
I cannot accept Ranbaxy’s argument that “the patentee intended the data set out
in the patent to promise a ten-fold increase in inhibiting the biosynthesis of
cholesterol in humans, not just in a test tube” (Ranbaxy’s Memorandum,
paragraph 23).
(ii) Subsection
27(3) analysis:
[56]
The Applications
Judge was wrong in interpreting the disclosure requirement of subsection 27(3)
of the Act as requiring that a patentee back up his invention by data. By so
doing, he confused the requirements that an invention be new, useful and non-obvious
with the requirement under subsection 27(3) that the specification disclose the
“use” to which the inventor conceived the invention could be put: see Consolboard,
supra, at 527. Whether or not a patentee has obtained enough data to
substantiate its invention is, in my view, an irrelevant consideration with
respect to the application of subsection 27(3). An analysis thereunder is
concerned with the sufficiency of the disclosure, not the sufficiency of the
data underlying the invention. Allowing Ranbaxy to attack the utility, novelty
and/or obviousness of the 546 patent through the disclosure requirement unduly
broadens the scope of an inventor’s obligation under subsection 27(3) and
disregards the purpose of this provision.
[57]
While it
is true that subsection 27(3) requires that an inventor “correctly and fully
describe” his invention, this provision is concerned with ensuring that the
patentee provide the information needed by the person skilled in the art to use
the invention as successfully as the patentee. The Supreme Court of Canada, in Consolboard,
supra, at 526, cited with approval the following passage from R. v.
American Optical Company et al (1950), 11 Fox Pat. C. 62 at p. 85:
… It is
sufficient if the specification correctly and fully describes the invention and
its operation or use as contemplated by the inventor, so that the public,
meaning thereby persons skilled in the art, may be able, with only the
specification, to use the invention as successfully as the inventor could
himself.
[Emphasis
added]
[58]
The
requirement that the specification of a patent be truthful and not be
misleading is not covered by subsection 27(3), but rather by subsection 53(1)
of the Act, which reads as follows:
|
Void in certain cases, or valid only for parts
53. (1) A patent is void if any material
allegation in the petition of the applicant in respect of the patent is
untrue, or if the specification and drawings contain more or less than is
necessary for obtaining the end for which they purport to be made, and the omission
or addition is wilfully made for the purpose of misleading.
|
Nul en certains cas, ou valide en partie seulement
53. (1) Le brevet est nul si la pétition du
demandeur, relative à ce brevet, contient quelque allégation importante qui
n’est pas conforme à la vérité, ou si le mémoire descriptif et les dessins
contiennent plus ou moins qu’il n’est nécessaire pour démontrer ce qu’ils
sont censés démontrer, et si l’omission ou l’addition est volontairement
faite pour induire en erreur.
|
[59]
Only two questions
are relevant for the purpose of subsection 27(3) of the Act. What is the
invention? How does it work?: see Consolboard, supra, at 520. In the
case of selection patents, answering the question “What is the invention?”
involves disclosing the advantages conferred by the selection. If the patent
specification (disclosure and claims) answers these questions, the inventor has
held his part of the bargain. In the case at bar, the 546 patent answers each
of these questions.
[60]
What is the
invention? The invention
consists of having identified an enantiomer, and in particular the calcium salt
of that enantiomer, that is better at inhibiting the biosynthesis of
cholesterol than would be expected, given the common knowledge and prior art at
the time of application for the patent.
[61]
How does it work? The 546 patent sets out the methods for
producing the compounds covered by the patent.
[62]
I also conclude that
the fact that the 546 patent does not provide a justification as to why the
calcium salt of atorvastatin is the preferred embodiment of the invention does
not render the disclosure insufficient. As I have already indicated, there is
no requirement that a patentee explain in the disclosure why and how his
invention is useful. When read as a whole, a skilled reader would understand
the patent as claiming that the calcium salt of atorvastatin is the compound
covered by the 546 patent that demonstrates the most surprising and unexpected
inhibition of cholesterol biosynthesis because it has the most preferred
physical properties. Pfizer was not required to include in the 546 patent data
which supports its statement that the calcium salt of atorvastatin is the
preferred embodiment of the invention, nor was it required to explain why the
calcium salt was the preferred embodiment.
(E) Conclusion on disclosure
under subsection 27(3)
[63]
The applications
judge erred in construing the promise of the patent and mischaracterized the
disclosure requirement under subsection 27(3) of the Act by asking whether
there was sufficient data to substantiate the promise of the patent. Such an
examination exceeds the scope of the provision. An attack on a selection patent
on the basis that there is no data to support the claimed advantage is
certainly relevant for the purposes of validity (most likely to the question of
utility), but it is not relevant with respect to disclosure under subsection
27(3) of the Act.
[64]
The patent must
disclose the invention and how it is made. The 546 patent does this. It also
discloses the advantages that underlie the selection. This, in my view, is the
extent of the requirement under subsection 27(3) of the Act, the purpose of
which is to allow a person skilled in the art to make full use of the invention
without having to display inventive ingenuity.
(F) Are the allegations of obviousness,
double patenting and anticipation justified?
[65]
I now turn to
Ranbaxy’s allegations of obviousness, double patenting and anticipation.
Because of his conclusion in regard to the subsection 27(3) issue, the Judge
made no findings as to whether Ranbaxy’s allegations under these headings were
justified.
[66]
In its NOA, Ranbaxy
alleges that the 546 patent is invalid for obviousness, double patenting and
anticipation. Pfizer counters these allegations by saying that because the 546
patent is a selection patent, its validity depends solely on it having
unexpected advantages over the class from which it is selected.
[67]
In Novopharm,
above, von Finckenstein J. examined the allegations of invalidity for
obviousness, double patenting and anticipation with respect to the 546 patent
and found that they were not justified. This conclusion was based on his
finding that the 546 patent was, on its face, a valid selection patent claiming
a tenfold advantage of atorvastatin over the racemate. In his view, the fact
that the 546 patent was a valid selection provided a complete answer to the
allegations of invalidity (see paragraphs 56 and 96 of his Reasons). In so
concluding, the Judge emphasized the fact that Novopharm’s allegations of
invalidity based on anticipation, obviousness and double patenting did not
challenge the 546 patent on the ground that it was not a valid selection, nor
did they challenge its utility.
[68]
In the present
matter, Ranbaxy challenges the validity of the 546 patent on the basis of
obviousness, double patenting and anticipation, but it does not, under those
headings, attack the sufficiency of the data that underlies the invention
claimed in the 546 patent. I therefore reach the same conclusion reached by von
Finkenstein J. in Novopharm, above, i.e. that the NOA does not
constitute a sufficient basis upon which to challenge the data underlying the
546 patent.
[69]
On its face, the 546
patent is a selection patent, the validity of which depends on it having
unexpected advantages over the class from which it is selected. By failing to
attack the data underlying the selection under the headings of anticipation,
obvious and double patenting, Ranbaxy has not challenged the validity of the
selection. Consequently, as von Finkenstein J.A. held in Novopharm,
above, there is no need to examine Ranbaxy’s allegations under those headings.
However, I will nonetheless say a few words regarding the issues of double
patenting and anticipation.
(i) Double
patenting:
[70]
Ranbaxy alleges, in
its NOA, that a number of the claims of the 546 patent are invalid for double
patenting (Appeal Book, Volume 1, pages 239-240):
Canadian Patent No.
1,330,441 (“the 441 Patent”), entitled “Process for
Trans-6-[2-(Substituted-Pyrrol-1YL)Alkyl] Pyran-2-One Inhibitors of Cholesterol
Synthesis”, have a filing data of February 7, 1989 and priority dates of
February 22, 1988 and February 1, 1989 based on U.S. Patent application Nos.
158,439 and 303,733 respectively, also issued to Warner-Lambert. The 441 Patent
was filed over a year prior to the filing of the 546 Patent.
The 441 Patent discloses
processes for preparation of, inter alia, atorvastatin lactone,
atorvastatin acid and pharmaceutically acceptable salts thereof. Further, the
441 Patent disclosure teaches atorvastatin acid at page 22, lines 1 to 3: “ a
dihydroxy acid and pharmaceutically accepted salts thereof, corresponding to
the opened lactone ring of compounds of structural Formula 1”.
The 441 Patent teaches
at page 2, lines 2 to 7, that the processes disclosed in the 893 U.S. Patent:
… do not produce
enantiomerically pure products. The materials produced by the earlier methods
can be separated in enantiomerically pure products but the process is very
expensive, time-consuming, and results in the loss of more than 50% of the starting
material.
The object of the
present invention is an improved process for preparing the compounds described
above by using a novel synthesis.
Example 3 of the 441
Patent teaches two step-by-step methods to produce atorvastatin lactone.
Further, the 441 Patent
discloses that the R(R*R*) single enantiomer is particularly valuable as a
hypolipidemic and hypocholesterolemic agent (page 1, I.18-25) and that it is
the preferred isomer (page 44, I.33-35).
[71]
Specifically with
respect to claim 6 of the 546 patent, the NOA provides (Appeal Book, Volume 1,
page 241):
As noted above, Claim 6
of the 546 Patent specifies the hemicalcium salt of atorvastatin acid recited
in claim 2 of the 546 Patent. Claim 12 of the 441 Patent claims, inter alia,
processes for making atorvastatin acid and pharmaceutically acceptable salts
thereof. The 441 Patent (p. 20, I.16) teaches calcium salts to be
pharmaceutically accepted salts. The calcium salt of atorvastatin acid would be
obvious to a person skilled in the art based on the disclosure and the
Monkhouse article, supra.
Accordingly, claim 6 of
the 546 Patent was not patentably distinct from claim 12 of the 441 Patent.
Therefore, claim 6 of the 546 Patent was without any novelty or ingenuity over
claim 12 of the 441 Patent, and is invalid for double patenting.
[72]
On the topic of
double patenting, the NOA concludes (Appeal Book, Volume 1, page 241):
The compounds of the 546
Patent do not result in a further invention over and above the end products of
the processes described in the 441 Patent. Thus, claims 1, 2, 3, 6, 11 and 12
of the 546 Patent do not exhibit any novelty or ingenuity over claims 12 and 14
of the 441 Patent and, therefore, claims 1, 2, 3, 6, 11 and 12 of the 546
Patent are invalid for double patenting.
[73]
In its Notice of
Application, Pfizer responds to this allegation as follows (Appeal Book, Volume
1, page 83):
The 441 Patent includes
claims for improved process of compounds […]. It does not claim [compounds][…]
as molecules exhibiting surprisingly potent activity as inhibitors of
cholesterol biosynthesis or having any other unexpected characteristics. Nor
does the 441 Patent claim atorvastatin calcium as a compound exhibiting
surprising potent activity as an inhibitor of cholesterol biosynthesis or
having any other unexpected properties.
In addition, the
allegation of double patenting based on the 441 Patent cannot be justified
because the 546 Patent expires before the 441 Patent and there is thus no
extension of the monopoly of the 546 Patent.
Claim 6 of the 546
Patent is patently distinct over the claims of the 441 Patent. There is no
double patenting as alleged by Ranbaxy.
[74]
Ranbaxy’s submission,
put at its simplest, is that the process claims of the 441 patent and the
product claims of the 546 patent are, in reality, two aspects of the same
invention. Hence, as a result, there is no ingenuity in taking the products
disclosed in the 441 patent and separately patenting them in the 546 patent.
Thus, the 546 patent is not patently distinct from the 441 patent.
[75]
In Pharmascience
Inc. v. Sanofi-Aventis Canada Inc., 2006 FCA 229, at paragraphs 67-68,
Sharlow J.A. summarized the law on double patenting as follows:
[67] “Double
patenting” refers to certain judge made rules that have been devised to prevent
the “evergreening” of patents. Evergreening is the undue extension of the
statutory monopoly in a particular patent by means of a series of patents with
obvious or uninventive additions (Whirlpool Corp. v. Camco Inc., [2000]
2 S.C.R. 1067, at paragraph 37).
[68] The
jurisprudence has so far identified two categories of double patenting. In the
first category, “same invention patenting”, two patents are the same or have
an identical or conterminous claim. The second category, “obviousness double patenting”,
is somewhat broader. In obviousness double patenting, the claims of the patents
are not identical or conterminous, but the later patent has claims that are not
patentably distinct from the other patent, or involve no novelty or ingenuity.
[76]
In my opinion, the
double patenting allegations are not justified. The 441 patent covers
processes, whereas the 546 patent covers compounds. As explained by Hughes
& Woodley (at §15, page 172), “[a] previous patent for a product produced
by a claimed process does not invalidate a later patent for the product alone
for reasons of double patenting” (see: Aventis Pharma Inc. v. Mayune Pharma
(Canada) Inc., [2005] F.C.J. No. 1437 at paragraphs 72-76 (Q.L.)).
[77]
Furthermore,
according to Hughes and Woodley (§15, page 172), “[w]here a patent has been
found to be a proper selection patent, therefore not obvious, there is no
double patenting” (see: Glaxo SmithKline Inc. v. Apotex Inc., [2003]
F.C.J. No. 886 at paragraph 48 (Q.L.)).
[78]
I therefore agree
with the following conclusion reached by von Finkenstein J. in Novopharm,
above, where he said:
[100] In same
invention double patenting, the claims must be identical or co-terminus. Since
the 441 Patent is a process patent, it is obviously not the same as the 546
Patent, which claims a compound. Given that the 546 Patent is a selection from
the group of compounds disclosed in the 768 Patent (the Canadian equivalent of
the US 893 Patent), the 546 Patent is obviously not identical with the claims
of the 768 Patent.
[101] As far as
obviousness double patenting is concerned, the claims or disclosure must
exhibit novelty or ingenuity in order for the second patent to be valid. (See Sanofi-Synthelabo
Canada Inc., supra at para. 86).
[102] As the Court
found that the 546 Patent was a selection patent, by definition it is novel and
unexpected. It thus cannot be invalid on the basis of obviousness double
patenting.
(ii)
Anticipation:
[79]
Ranbaxy submits that
the 546 patent is anticipated by the 768 patent which discloses atorvastatin
calcium. The NOA attacks the novelty of the 546 patent as follows (Appeal Book,
Volume 1, page 244):
If on the construction
of the 768 Patent, its claims are found to include th R(R*R*) enantiomer, then
Claims 1, 2, 3, 6, 11 and 12 of the 546 Patent are invalid as lacking novelty
in light of the 893 U.S. Patent (which corresponds to the 768 Patent). On that
construction, the 893 Patent would disclose the R(R*R*) enantiomer and
pharmaceutically acceptable salts thereof for use as a hypocholesterolemic or
hypolidemic agent. All essential elements of Claims 1, 2, 3, 6, 11 and 12 of
the 546 Patent would then be found in the 893 U.S. Patent. Those claims would
not be novel, hence they would be invalid.
[80]
Pfizer responds to
this allegation in its Notice of Application, as follows (Appeal Book, Volume
1, page 83):
Ranbaxy also asserts
that claim 6 of the 546 Patent is invalid by reason of lack of novelty in view
of the 893 Patent. This assertion is without merit. Claim 6 of the 546 Patent
claims subject-matter which is novel over the disclosure of the 893 Patent.
Claim 6 is not anticipated by the 893 Patent.
[81]
The test for
anticipation was enunciated by this Court in Beloit Canada Ltd. v. Valmet OY
(1986), 8 C.P.R. (3d) 289, which the Supreme Court of Canada adopted in Free
World Trust v. Electro Santé Inc. (2000), 9 C.P.R. (4th) 168:
One must, in effect, be
able to look at a prior, single publication and find in it all the information
which, for practical purposes, is needed to produce the claimed invention
without the exercise of any inventive skill. The prior publication must
contain so clear a direction that a skilled person reading and following it
would in every case and without possibility of error be led to the claimed
invention.
[Emphasis
added]
[82]
In Pfizer Canada
Inc. v. Canada (Minister of Health), 2006 FCA 214, this Court made it clear
that the test for anticipation was a difficult one to meet. At paragraph 36,
Malone J.A. put it as follows:
[36] This is a
difficult test to meet. The Applications Judge held that a person skilled in
the art would not know why to select Besylate as one of the initial choices of
salt, would not know whether it would form a salt of amlodipine in the solid
state and would not know the particular properties of Besylate or their
advantage for pharmaceutical formulation. As a result of these facts, he found
that a person skilled in the art would not in every case and without
possibility of error be led to the claimed invention. In so doing he did not
make a palpable and overriding error because there was evidence on which to
base his findings.
[83]
The allegation of
anticipation, in my view, is not justified. A claim to a specific chemical
compound cannot be anticipated by a prior art reference which only teaches a
broad class of genus of compounds into which the compound falls because the
prior art reference does not give directions which inevitably result in the
specific compound (see Sanofi-Synthelab Canada Inc. et al v. Apotex Inc. et
al (2005), 39 C.P.R. (4th) 202 at paragraph 55, affirmed 2006
FCA 421 at paragraphs 25-27; Pfizer Canada Inc. v. Apotex Inc., [1997)
F.C.J. No. 1087 (Q.L.), 77 C.P.R. (3d) 547 (T.D.); Pfizer Canada Inc. v.
Canada (Minister of Health), 2006 FCA 214, [2006] F.C.J. No. 894 (Q.L.)).
Ranbaxy did not allege that the prior art teaches that the calcium salt of
atorvastatin would have greater inhibition activity than expected, i.e. more
than two-fold.
CONCLUSION
[84]
For these reasons, I
would allow the appeal, set aside the judgment of the Federal Court and,
rendering the judgment which ought to have been rendered, I would prohibit the
Minister from issuing a Notice under section C.08.004 of the Food and Drug
Regulations to Ranbaxy for atorvastatin calcium, until after the expiry of
the 546 patent. I would also allow Pfizer its costs both in the appeal and in
the application.
“M. Nadon”
“I
agree.
A.M.
Linden J.A.”
“I
agree.
C. Michael Ryer J.A.”
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