Date: 20090716
Docket: T-1837-07
Citation: 2009 FC 726
BETWEEN:
PURDUE
PHARMA
Applicant
and
PHARMASCIENCE INC. AND
THE MINISTER OF HEALTH
Respondents
PUBLIC REASONS FOR ORDER
HARRINGTON J.
[1]
The
issue in this application is whether any one of Pharmascience’s barrage
of allegations of invalidity with respect to Purdue’s patent for
“Controlled Release Oxycodone Compositions” is justified. If so,
the Court will not prevent the Minister of Health from permitting Pharmascience
to market its generic version of oxycodone hydrochloride controlled release
tablets. If not, the Minister will be prohibited from giving it the go-ahead (a
Notice of Compliance) until Purdue’s patent expires in 2012.
[2]
Although
Pharmascience was entitled to assert as many grounds of invalidity as it saw
fit, I think it fair to say that if Purdue had not claimed such a broad
range of methods to control or spread out over time the dissolution of oxycodone
within the body, these proceedings would have been moot.
[3]
This
application was taken by Purdue pursuant to the Patented Medicines (Notice
of Compliance) Regulations. Although byzantine in nature, they are so
well-known that they need not be analyzed in detail here. See for instance Merck
Frosst Canada Inc. v. Canada (Minister of National Health and Welfare),
[1998] 2 S.C.R. 193, 80 C.P.R. (3rd) 368, Brystol-Myers Squibb Co. v. Canada
(Attorney General), 2005 SCC 26, [2005] 1 S.C.R. 533, 39 C.P.R. (4th) 449 (Biolyse)
at paragraphs 5-24, Apotex Inc. v. Sanofi-Synthelabo Canada Inc., 2008
SCC 61, [2008] 3 S.C.R. 265, 69 C.P.R. (4th) 251 (Plavix) at paragraphs
7 and 12-17, as well as the decision of Mr. Justice Hughes in Ferring Inc.
v. Canada (Minister of Health), 2007 FC 300, 55 C.P.R. (4th) 271.
[4]
Suffice
it to say that Purdue’s Canadian patent 2,098,738 (‘738), which
claims a novel 12-hour controlled release formulation of oxycodone having a
specific pharmacokinetic profile, is on the list maintained by the Minister
pursuant to s. 4 of the Regulations. As Pharmascience filed an Abbreviated New
Drug Submission comparing its tablets to Purdue’s, in order to get to
market sooner rather than later it was required to give Purdue a Notice of
Allegation to which Purdue, in turn, responded by seeking a prohibition order.
That mere application serves, in effect, as a statutory injunction for up to
two years.
[5]
I
shall deal with the application as follows:
|
|
Paragraph(s)
|
|
Patents
of Invention – A Few Basics
|
6 – 20
|
|
Oxycodone
and Patent ‘738
|
21 – 34
|
|
Skilled
Addressee
|
35
|
|
The
Expert Witnesses
|
36 – 47
|
|
Analysis
|
48 – 63
|
|
Development
of Patent ‘738
|
64 – 75
|
|
Grounds
of Invalidity
|
76 – 116
|
|
Anticipation
|
78 – 82
|
|
Obviousness
|
83 – 100
|
|
Sound
Prediction of Usefulness
|
101 – 104
|
|
Overbreadth
and Lack of Disclosure
|
105 – 116
|
|
Conclusion
|
117 – 118
|
PATENTS OF INVENTION
– A FEW BASICS
[6]
An
invention need not be patented. If it is, however, the patent is construed as a
bargain between the inventor and the public. In consideration of disclosing the
invention and how to work it, the inventor is given a temporary monopoly to
exploit it, currently 20 years retroactive to the date the application was
filed.
[7]
What
governs this case is the Patent Act as in force when the application was
filed in November 1992. References to specific sections of the Act are
references to the sections as they were at that time. The patent is notionally
addressed to a person skilled in the art or science of the subject-matter and
is to be read as such a person would have read it when it first became public (Patent Act, s.
34). It is the specification thereof which discloses the invention and how to
work it. The specification ends with a claim or list of claims over which a
monopoly is asserted.
[8]
To
be patentable an invention must be both new and shown to be useful, either by
demonstration or by sound prediction. An invention may be new even if only an
improvement on what already exists, and may be useful even if only a poorer
alternative to what already exists. The inventor of a new pain killer will
not be denied a patent simply because it is only half as effective as aspirin
and twice as expensive.
[9]
The
patent is written by or for the inventor and its language must be carefully
construed. It is addressed to those who are able to “make, construct,
compound or use it” (s. 34(1)(b) of the Act), which, it goes
without saying, is not the Court. The Court is likely to need the assistance of
experts to determine if what is claimed to be invented is new and useful, and
to give meaning to such technical language as may be found in the claims.
[10]
As
stated, language is crucial. There tends to be a tension between what, if
anything, was invented and what the inventor claims to have invented. If, which
is not the case here, more was invented than claimed, the Court will not save
the day by giving effect to the “spirit” of the invention. If, on
the other hand, the inventor claims or promises more than what was invented,
the patent is invalid. To minimize this possibility the inventor asserts
cascading claims, each narrower than the other. Such limitations serve as a
potential safety net so that, if the broadest claims fall, the monopoly may be
saved in part by the more modest claims. Mr. Justice Binnie has described them
as “...complex layers of definitions of different elements (or
“components” or “features” or “integers”)
of differing complexity, substitutability and ingenuity)...” (Free
World Trust v. Électro Santé Inc., 2000 SCC 66, [2000] 2
S.C.R. 1042, 9 C.P.R. (4th) 168, at paragraph 15).
[11]
The
claims are to be read in an informed and purposeful way so as to permit
fairness and predictability and to define the limits of the monopoly. The
claims cannot be so largely construed as to permit the patentee to monopolize
anything that achieves a desired result. On the other hand, one should not be
permitted to avoid the monopoly by using a non-essential variant which makes no
material difference to the working of the invention.
[12]
Some
elements of the claimed invention are essential, while others are not, based
either on common knowledge when the invention was made public, or according to
the inventor’s intent, expressed or implied, gleaned from the claim
language. It is only such novel features that the inventor claims are essential
that constitute the “pith and marrow” of the claim.
[13]
In
construing the meaning of a claim, recourse should be had to the disclosure to
gain insight into what was meant by a particular word or phrase. Otherwise the
scope of the claim or claims as written and so understood can be neither
restricted nor enlarged.
[14]
These
principles are drawn from Free World, above, and Whirlpool
Corp. v. Camco Inc., 2000 SCC 67, [2000] 2 S.C.R. 1067, 9 C.P.R. (4th) 129.
[15]
Patents
are strictly a creature of statute and so these cases, as well as those earlier
Canadian, English and American cases referred to therein, are all based on the
specific language of the various Patent Acts as in force in those
jurisdictions from time to time. The general principles therein enunciated
cannot be severed from the statutory language under consideration.
[16]
The
“newness” requirement is found in the definition of
“invention” set out in s. 2 of the Act. The definition specifically
provides that the patent may simply be an improvement, as does s. 32.
[17]
To
drill down into “newness”, ss. 27(c) and (d) provide that the claim
must not have been previously disclosed (and must not have been previously
obvious to a person skilled in the art or science to which it pertains).
“Previous” means more than one year before the filing of the
application.
[18]
Finally,
pursuant to the Regulations, the presumption of validity set out in s.
43 of the Act is displaced as long as the person issuing the Notice of
Allegation leads any evidence of invalidity. Thereafter, the burden falls upon
the applicant, in this case Purdue, to prove on the balance of probabilities
that no such allegation was justified. The steps to take into account in
considering the burden as to validity were clearly summarized by Mr. Justice
Hughes in Pfizer Canada Inc. v. Canada (Minister of Health), 2008 FC 11,
69 C.P.R. (4th) 191 at paragraph 32 and recently reiterated in Eli Lilly
Canada Inc. v. Novopharm Ltd., 2009 FC 235 at paragraphs 22 through 25.
[19]
The
shortcomings and limited value of PM (NOC) applications are well-known. The evidence
of the experts consists of affidavits and cross-examinations. These witnesses
are supposed to aid the Court in explaining technical terms and in advising as
to what was commonly known in the field at relevant times. Yet the judge is
unable to ask clarifying questions and, because of lack of personal
observation, is hard-pressed to form a view as to whether an opinion is
overblown and whether what is said to have been previously disclosed or obvious
comes with the benefit of hindsight.
[20]
All
that is to be decided in this application is whether the Minister is to be
prohibited from issuing Pharmascience a Notice of Compliance. Determinations as
to the validity of the patent are not even binding on the parties themselves.
This must be kept in mind, as the invention has been the subject of litigation
in other jurisdictions. More particularly, Purdue has drawn to my attention the
decision of Mr. Justice Floyd in Ratiopharm GmbH v. Napp Pharmaceutical
Holdings Ltd., [2008] EWHC 3070 (Pat), [2009] R.P.C. 11. He held that the claims
of the patent which were under attack there (which are not the same as the ones
under attack here) were valid and were not infringed. The Court of Appeal,
[2009] EWCA Civ 252, agreed that the claims were valid but held that they were infringed.
Since, at the end of the day, Pharmascience did not pursue any allegation of
non-infringement, that question is not directly before me.
OXYCODONE AND PATENT
‘738
[21]
Patent
‘738 is titled “Controlled Release Oxycodone Compositions”.
Oxycodone is not new and neither are ways and means of spreading out the
release of a medicine into the blood stream over time. An obvious advantage of
a controlled release tablet taken by mouth is that, if effective over a longer
period of time, the medicine may be taken less frequently. Most anyone would
rather take a pill every 12 hours than every 4 or 6 hours. The amount of the
medicine in play at any one time should also be more consistent.
[22]
Oxycodone
has been in use since 1917 and is not covered by any current patent. It is one
of a group of medications known as “opioid analgesics” that relieve
pain by acting upon various opioid receptors in the body, in this case what are
known as mu receptors. They are natural, semi-synthetic or synthetic
derivatives of opium. Oxycodone is semi-synthetic. The very word
“opium” conjures up fears of addiction. It is common ground,
however, that if carefully and professionally administered for proper purposes,
the fear of addiction is overstated. Opioids include morphine, codeine, dihydrocodeine,
heroin, hydromorphone, oxycodone and methadone. Opioids have both common and
dissimilar characteristics and may produce different nasty side effects in
different people.
[23]
The
patent application was filed in Canada in November 1992, and asserts priority
based on a U.S. patent
application filed in November 1991. It was published, i.e. laid open, here in
May 1993. These dates are important because yesterday’s news is old hat. As
regards novelty and obviousness, the reference date is the priority date of
November 1991. Utility is assessed against the Canadian filing date in November
1992 and construction and sufficiency against the date of publication in May
1993. Pharmascience argues that Purdue cannot rely on the priority date because
the U.S. patent specification
is somewhat different. In the light of my findings nothing turns thereon.
[24]
According
to Purdue, the patent specification discloses an invention with three primary elements:
1) the choice of oxycodone as the active ingredient for a product to be used in
the treatment of moderate to severe pain; 2) the choice of a particular
pharmacokinetic profile; and 3) the development of formulations which would
result in the type of profile being sought (12-hour controlled release).
Pharmacokinetics is that branch of pharmacology which deals with the movement
of drugs within the body. Each of these three elements is considered essential
to the invention. Put another way, in order for Pharmascience’s product
to infringe, it must fall within each of these three elements.
[25]
In
broad strokes, Pharmascience’s allegations are to the effect that the
patent discloses nothing new or useful. In the alternative, in some respects
the patent falls short of what was promised, and even if something new and
useful was invented, the claims in issue are overbroad and capture, in the
same breath, matters which were old or useless. Consequently, the claims in
issue are invalid.
[26]
More
specifically, Pharmascience alleges that the two claims in question, claims 5
and 11, are invalid for any of these three prime reasons: overbreadth,
obviousness and false promise. They are also invalid for anticipation,
ambiguity, insufficiency, lack of invention, lack of sound prediction and lack
of utility.
[27]
Turning
now to patent ‘738 itself, the Abstract states:
A method for substantially reducing the
range in daily dosages required to control pain in approximately 80 % of
patients is disclosed whereby an oral solid controlled release dosage
formulation having from about 10 to about 40 mg of oxycodone or a salt thereof
is administered to a patient. The formulation provides a mean maximum plasma
concentration of oxycodone from about 6 to about 60 ng/ml from a mean of about
2 to about 4.5 hours after administration, and a mean minimum plasma
concentration from about 3 to about 30 ng/ml from about 10 to about 14 hours
after repeated “q12h” (i.e., every 12 hours) administration through
stead-state conditions. Another embodiment is directed to a method for
substantially reducing the range in daily dosages required to control pain in
substantially all patients. The figure is a graph showing the mean plasma
oxycodone concentration for a 10 mg controlled release oxycodone formulation
prepared in accordance with the present invention and a study reference
standard.
[28]
The
patent, which contains 47 pages of text, tables, examples and charts, includes,
as required, a specification, being a disclosure which ends with claims of what
has been invented (in this case 28 claims). By way of background it is
stated with respect to opioid analgesics in general that approximately an 8-fold
range in daily dosages is required to control pain in approximately 90 percent
of patients. Humans relate to pain and pain relief quite differently. The wide
range makes titration difficult and leaves the patient without appropriate pain
control for unacceptably long periods. Titration is the made-to-measure
dosage suitable for each individual patient, i.e. optimal relief while avoiding
toxicity. According to the inventors, the invention provides methods and
formulations which improve the efficiency and quality of pain management,
substantially reduce variability and daily dosages, and the time and resources
needed to titrate patients.
[29]
The
specification describes various solid oral dosage forms containing about 10 to
about 160 mg of oxycodone, or a salt thereof, in which release after
ingestion is spread out either by a retardant coating or by a matrix. A matrix
system consists of an active ingredient, in this case oxycodone, being
dispersed homogeneously throughout a matrix of inert, erodible or
swelling-controlled material, generally a polymer. It calls for certain
dissolution ranges in vitro and blood plasma levels over time, “substantially
independent of pH”.
[30]
Although
only claims 5 and 11 of the 28 claims are alleged to be invalid, particular
attention must also be given to claim 9 from which claim 11 is derived.
[31]
Claim
5:
A solid controlled release
oral dosage form, comprising oxycodone or a salt thereof in an amount from
about 10 to about 160 mg said oxycodone or salt thereof being dispensed in
a matrix which includes;
an effective amount of a
controlled release matrix selected from the group consisting of hydrophilic
polymers, hydrophobic polymers, digestible substituted or unsubstituted
hydrocarbons having from about 8 to about 50 carbon atoms, polyalkylene
glycols, and mixtures of any of the foregoing; and
a suitable amount of a
suitable pharmaceutical diluent, wherein said composition provides a mean
maximum plasma concentration of oxycodone from about 6 to about 240 ng/ml from
a mean of about 2 to about 4.5 hours after administration, and a mean minimum
plasma concentration from about 3 to about 120 ng/ml from a mean of about 10 to
about 14 hours after repeated administration every 12 hours through steady-state
conditions.
[32]
Claim
9:
A controlled release tablet
for oral administration comprising from about 10 to about 160 mg oxycodone or
an oxycodone salt dispersed in a controlled release matrix, said tablet
providing an in-vitro dissolution of the dosage form, when measured by the USP
Paddle Method at 100 rpm at 900 ml aqueous buffer (pH between 1.6 and 7.2)
at 37o C, between 12.5% and 42.5% (by wt) oxycodone released after 1
hour, between 25% and 55% (by wt) oxycodone released after 2 hours, between 45%
and 75% (by wt) oxycodone released after 4 hours and between 55% and 85% (by
wt) oxycodone released after 6 hours, the in vitro release rate being
substantially independent of pH and chosen such that a mean maximum plasma
concentration of oxycodone from about 6 to about 240 ng/ml is obtained in vivo
from a mean of about 2 to about 4.5 hours after administration of the dosage
form, and a mean minimum plasma concentration from about 3 to about 30 ng/ml
from a mean of about 10 to about 14 hours after repeated administration every
12 hours through steady-state conditions.
[33]
Claim
11:
A dosage form according to
claim 9, wherein the in vitro dissolution rate is between 17.5% and 32.5% (by
wt) oxycodone released after 1 jour, between 35% and 45% (by wt) oxycodone
released after 2 hours, between 55% and 65% (by wt) oxycodone released after 4
hours between 65% and 75% (by wt) oxycodone released after 6 hours.
[34]
The
real nub of Pharmascience’s complaint is that it proposes using
hydroxypylmethycellulose (HPMC) in its matrix, which would appear to fall
within the group of matrixes claimed. HPMC is specifically mentioned in the
disclosure.
SKILLED ADDRESSEE
[35]
The
parties agree, and the Court has no reason to disagree, that the person skilled
in the art or science to which the patent relates has three special skill sets.
Such a person, or persons, would have some years of academic training and
practical experience in pharmacokinetics, formulation chemistry and clinical
pain treatment.
THE EXPERT WITNESSES
[36]
Purdue
called two of the four American inventors: Benjamin Oshlack, a
formulator, and Dr. Robert Kaiko, whose background was in pharmacokinetics
but, because of earlier years at the Sloan Kettering Institute for Cancer
Research, was also familiar with clinical pharmacology as regards pain
relievers and pain management. Although they have the skill sets required, the
patent obviously is not addressed to them. Rather, they set out in considerable
detail what they invented and how they went about it. They are treated as fact
witnesses.
[37]
The
experts called by both sides were all superbly qualified to assist the Court
and their expertise was not put in doubt. Although they all assisted the Court,
some went beyond giving the technical information necessary to construe the
patent and construed it themselves. Keep in mind that “Claims
construction is a matter of law for the judge, and he was quite entitled to
adopt a construction of the claims that differed from that put forward by the
parties” (Whirlpool, para. 61).
[38]
Purdue
called four experts:
a. Dr. Donald
Stanski who dealt with pharmacokinetics;
b. Dr. Roland
Bodmeier, a formulator;
c. Dr. Louis
Cartilier, another formulator; and
d. Dr. Romaine
Gallagher who has considerable experience in pain management.
[39]
Pharmascience
also called four experts:
a.
Dr.
Christopher Rhodes, a formulator;
b.
Dr.
Donald Denson who deals with pharmacokinetics;
c.
Dr.
Stephen Abram who specializes in anaesthesiology and pain management; and
d.
Dr.
Gerhard Levy who also dealt with pharmacokinetics.
[40]
Dr.
Stanski, currently employed by Novartis International AG, is an anaesthesiologist,
was a member of the Faculty of the Department of Anesthesia at Stanford University, School of Medicine, from 1979
to 2005, and spent five years as Chairman of that Department. In addition to
being currently employed by Novartis, he has a two-year public service
appointment to the United States Food and Drug Administration where he is a Scientific
Advisor to the Director, Centre for Drug Evaluation and Research. During his
years with Stanford he also had commercial experience and established a
clinical practice at the Palo Alto Veterans Administration Hospital.
[41]
Dr.
Bodmeier is Professor of Pharmaceutical Technology at the College of Pharmacy,
Freie Universität Berlin, Germany. He obtained his Ph.D. in
Pharmaceutics in 1986 from the University of Texas at Austin
where he was an Associate Professor before joining the Freie Universität Berlin. His major
research interests relate to controlled drug delivery systems and would qualify
him for present purposes as a formulator, which is not to suggest that the
three special attributes of the skilled addressee are mutually exclusive.
[42]
Dr.
Cartilier, who received his Ph.D. in Pharmaceutical Science at l’Institut
de Pharmacie of the Université Libre de Bruxelles, had been a Post-Doctoral
Fellow at the Université de Montréal where he has taught since
1989. He is currently titular Professor with the Faculty of Pharmacy and
considers himself primarily an academic formulator, although he has been
consulted by the pharmaceutical industry on a number of occasions.
[43]
Dr.
Gallagher is a family doctor in Vancouver. She has considerable
experience in pain management and has served as Director of the Palliative Care
Division in the Department of Family Medicine at the University of British
Columbia.
She has been on the faculty since 1996 and holds the rank of Clinical
Professor.
[44]
Dr.
Rhodes obtained his Ph.D. in Pharmacy from the Faculty of Medicine of the
University of London in 1964 and
for many years was Professor and Chair of the Department of Pharmacy Practice at
the University
of Rhode Island.
[45]
Dr.
Denson obtained his Ph.D. in Organic Chemistry from the University of Georgia in 1970. He
is currently an Assistant Professor of Anesthesiology at the Emory University
School of Medicine and Director of their Anesthesiology Research Laboratories. He
deals with pharmacokinetics.
[46]
Dr.
Abram graduated with his medical degree from Jefferson Medical College in 1970. He is
a physician specializing in the practice of anaesthesiology and pain management,
is currently a Professor in the Department of Anesthesiology at the Medical
College of Wisconsin in Milwaukee and serves as Director
of its Pain Fellowship Program.
[47]
Dr.
Levy obtained his Doctorate in Pharmaceutics from the University of California, San Francisco
in 1958 and, after a long and distinguished career, is currently the University
Distinguished Professor of Pharmaceutics Emeritus at the State University of
New York in Buffalo. He served
as Director of the Clinical Pharmacokinetics Research Center from 1978 to
1988, and has been a consultant to the World Health Organization, the United
States Food and Drug Administration and the pharmaceutical industry. He has
been called the father of pharmacokinetics.
ANALYSIS
[48]
I
mention two issues at the outset in order to immediately discard them: anticipation
by prior use and commercial success.
[49]
Pharmascience
has alleged that the invention had been previously anticipated by prior use.
That use consisted of in vivo testing. The experts agree that in
vitro (in a beaker) testing might give an indication of promising results,
but that in vivo testing is also necessary. The allegation is to the
effect that the clinical study on humans commissioned by Purdue was not
sufficiently confidential. However, the evidence of Dr. Miguel Zinny, Medical
Director of Medical Technical Research Associates Inc. in the United
States,
who acted as principal investigator, completely refutes that allegation.
[50]
I
also put no value on Purdue’s evidence that controlled release oxycodone
has been a commercial success. Commercial success may serve as a secondary
indication that there was a need in the market place which was fulfilled by
something new and useful (Janssen-Ortho Inc. v. Novopharm Ltd., 2007 FCA
217, 59 C.P.R. (4th) 116). Purdue produced sales records and hearsay
prescription records. Dr. Abram was of the view that controlled release oxycodone
was a commercial success in the United States because of
Purdue’s marketing. Dr. Gallagher did not recall a particular marketing
effort in Canada. Lawyers and
judges do not need lessons in logic. The data supplied cannot possibly lead to
the inference that this particular patent is valid. We are in the realm of
conjecture. Furthermore, neither Dr. Abram nor Dr. Gallagher has expertise in
the market place. They have stepped outside their expert qualifications. Courts
must treat such evidence with great care. See the comments of Mr. Justice
Goudge of the Ontario Court of Appeal in the Inquiry into Pediatric Forensic
Pathology in Ontario, in volume 2, chapter 8, with respect to evidence
beyond expertise and speculative evidence.
[51]
As
to the other allegations of invalidity, the approach thereto urged upon me by
Purdue is that allegations should be treated as separate and distinct and are
watertight compartments, with limited leakage. Pharmascience is criticized for
asserting a number of allegations in the same breath. For instance, one of the
headings in its written memorandum is “’738 Patent - Nothing Was
Invented (Obviousness, Anticipation, No Invention, Lack of Utility).”
However, I prefer the “seamless garment of the law” approach since,
after all, the patent is a legal document, a regulation within the meaning of
the Interpretation Act. I can do no better than to refer to Eli Lilly
Canada Inc. v. Apotex Inc., 2008 FC 142, 63 C.P.R. (4th) 406, where Mr.
Justice Hughes said:
[64] I have deliberately bundled all
of the topics listed in the title of this portion of these Reasons,
“Anticipation/Obviousness/Sound Prediction/Sufficiency of
Disclosure” together. There is one issue to be considered namely, the
validity of the ’356 patent. There is a tendency in the jurisprudence to
pigeonhole arguments respecting validity into certain categories such as
“anticipation” or “obviousness” and so forth. Each
category has collected about itself an accumulation of jurisprudence. Each
category tends to be argued separately creating, on occasion, contradictions,
inconsistencies and gaps. This is an occasion when one should step back and
examine the fundamentals of the patent system and determine whether a more
holistic approach is appropriate.
[52]
After
reviewing the patent system he concluded:
[74]
Thus, one must both advance the state of the art and disclose that
advance in order to gain the patent monopoly. Failing to do so, thus
invalidating the monopoly, can be in the form of one or more of several matters
such as, the “invention” was not new, or the so-called invention
was “obvious” or the disclosure was “insufficient” or
“what you disclosed doesn’t support the monopoly that you
claim”.
[75]
The factual circumstances of each case must be canvassed before trying
to examine them through the lens of any particular argument as to validity to
determine if truly, a proper invention has been made and whether it has been
properly disclosed and whether it has been properly claimed.
[53]
Although
I agree with Pharmascience that oxycodone was not new, that its use to
alleviate moderate to severe pain was not new, that controlled release formulations
of opioids were not new and even that a controlled release formulation of oxycodone
had been previously disclosed, it does not necessarily follow that the patent
is invalid. As Mr. Justice Martland stated in Ciba Ltd. v. Commissioner of
Patents, [1959] S.C.R. 378 at page 383:
…The method may be known and the
materials may be known, but the idea of making the application of the one to
the other to produce a new and useful compound may be new, and in this case I
think it was.
See also Free World, above, at
paragraphs 23 and 30.
[54]
I
am satisfied on the evidence that the creation of a 12-hour controlled release oxycodone
tablet in different dosages was new and useful. The real question is whether
claims 5 and 11 have been written in such a way to monopolize things which were
not invented at all, particularly HPMC matrixes.
[55]
Certainly
the selection of oxycodone for the treatment of moderate to severe pain was not
inventive. Although oxycodone was generally prescribed for the treatment of mild
to moderate pain, the prime reason was that it was formulated with other
medicines such as aspirin or acetaminophen. To prescribe such tablets in
sufficient quantity to relieve moderate to severe pain, the resulting levels of
aspirin or acetaminophen might be toxic. However, the evidence of Dr. Abram and
Dr. Gallagher is that immediate release oxycodone without a co-medicine
was available in both Canada and the United States. Dr. Gallagher
complained that only a 10 mg tablet was available which was impractical in
treating cancer patients who might need 300 mg a day. This has nothing to do
with potency and everything to do with convenience. The fact of the matter is
that oxycodone HCL trihydrate was available in Canada in 10 mg
tablets in a product known as Supeudol, and another product, Roxicodone, was
available in the United States. According to the Compendium of
Pharmaceuticals and Specialties 1988, published by the Canadian
Pharmaceutical Association, Supeudol was indicated for the relief of moderate
to severe pain. As with other narcotics, precautions were stated to be necessary
because of potential addiction and respiratory depressant effects, among other
things. In any event, claims 5, 9 and 11 do not specifically promise relief
from a particular intensity of pain.
[56]
In
Ratiopharm v. Napp, above, Mr. Justice Floyd said at paragraph 219 that
“…it would not occur to a skilled team in 1991 to
place oxycodone on a list of potential alternatives to morphine for making into
an oral controlled release formulation.” Morphine was generally considered to be
the gold standard. That finding of fact was based on the evidence before him.
No mention was made of the Canadian Compendium. I find that immediate release
oxycodone was known to effectively treat a wide range of pain. To then consider
a controlled release tablet does not constitute a quantum leap.
[57]
Other
opioids were available in controlled release formulations. Morphine was
available and Mr. Oshlack himself had disclosed and claimed an oxycodone
controlled release formulation in U.S. patent 4,861,598, a
patent which disclosed formulations which could be used for a number of opioids.
In addition, Purdue, through its Mr. Goldie, had U.S. patents on
two other controlled release opioids, hydromorphone and dihydrocodeine.
[58]
Bearing
in mind that each claim should be taken as self-standing (or in conjunction
with its progenitor such as claims 9 and 11), a number of
Pharmascience’s allegations can be quickly dismissed.
[59]
The
patent discloses that controlled release oxycodone would be effective under a
narrower dosage regime when compared to controlled release morphine. Pharmascience
alleges that this narrower range was never demonstrated and that there was no
sound basis for making that prediction. Be that as it may, that so-called
reduction in dosage does not form part of the language used in claims 5, 9 and
11 and cannot be implied by an overall reading of the specification.
[60]
To
quote from the disclosure: “In yet another aspect the present invention
provides a method for substantially reducing the time and resources need(ed) to
titrate patients requiring pain relief on opioid analgesics.” This
statement has been attacked as not being proven and pointless in that titration
is usually first established with immediate release tablets, before moving on
to a single dose of a controlled release tablet and then to a regular regime of
controlled release dosages. However, again, these assertions do not form part
of claims 5, 9 or 11.
[61]
Claims
5, 9 and 11 relate to two profiles, an in vitro dissolution profile and
an in vivo pharmacokinetic profile. Both may be envisaged as a line
running from left to right within a rectangle. In both, the horizontal is
marked from ingestion to 12 hours hence, i.e. Tmin and Tmax. In the in vitro
profile, the amount of dissolution is measured at various times, as shown on
the vertical. Claim 9 is for a release of between 12.5 percent and 42.5 percent
by weight in the first hour, between 45 and 75 percent after 4 hours and so on.
Claim 11 is narrower.
[62]
In
the pharmacokinetic in vivo profile, the vertical is measured by the
mean maximum plasma concentration of oxycodone from administration onwards. The
concentration from about 6 to about 240 ng/ml from a mean of about 2 to about
4.5 hours after administration drops to from about 3 to about 120 ng/ml. at
about 10 to about 14 hours after repeated administration every 12 hours through
steady-state conditions (Cmax and Cmin). This wide range is attributable to the
fact that the active ingredient is oxycodone, or a salt thereof, in an amount
ranging from about 10 to about 160 mg dispensed through a matrix.
[63]
It
is significant that these claims deal with a matrix. The product which was
eventually found in England to infringe the U.K. patent
controlled the release of oxycodone through an exterior coating. Apart
from matrixes and coatings, there are many other ways to control the release of
the active ingredient. Dr. Bodmeier refers to reservoir devices, osmotic
systems and swelling systems.
DEVELOPMENT OF PATENT
‘738
[64]
Patent
‘738 derives in large measure from the collaboration of two of the named
inventors, Benjamin Oshlack and Dr. Robert Kaiko, who at relevant times were
employed by Purdue Pharma L.P., a corporation based in the United
States
with which the Applicant is affiliated. Mr. Oshlack, a formulator,
joined Purdue in 1980. During the four years prior thereto he was employed in
the Netherlands at a company
which later became associated with Purdue. While there, his primary work was on
immediate release tablets.
[65]
After
joining Purdue, and after a stint at its United Kingdom affiliate,
Napp, where he obtained formal training in the development of controlled
release formulations, he worked with a number of products including oxycodone
and other opioids, focussing on the development of controlled solid dosage
forms.
[66]
By
the early 1980s, Napp had developed a controlled released morphine product: MS CONTIN.
Release was controlled by a matrix which included, among other things, a
cellulose polymer and a higher aliphatic alcohol. The CONTIN
system produced a pharmacokinetic profile in which the peak concentration of
morphine occurred relatively early compared to other controlled release
formulations, followed by a decrease in concentration.
[67]
MS
CONTIN became a commercial success upon its market entry in the United
States
in 1985. It meant a patient could be treated with morphine outside the
hospital, allowed for a more sustained release over time, and did not have to
be taken as frequently.
[68]
Mr.
Oshlack was not involved in the early stages of MS CONTIN but was involved in
the development of a controlled release codeine formulation based on the CONTIN
system. Initial experiments with a codeine salt were not successful as the
dissolution rate was too fast for twice-a-day administration. However, by
ultimately combining a codeine salt with freebase codeine within the CONTIN
system, a better dissolution profile was established and, after the formulation
was tested in humans, it was eventually developed into a commercial product.
[69]
Mr.
Oshlack actually began to experiment with controlled release oxycodone tablets
in 1981. He used oxycodone hydrochloride which was released too quickly. Then,
based on his experience with codeine, he tried a combination of oxycodone salt
and freebase oxycodone which still released too quickly in the in vitro dissolution
profile.
[70]
It
was really with Dr. Kaiko’s arrival at Purdue in 1985 that things began
to happen. Dr. Kaiko was very keen on an in vivo blood plasma
profile with an early peak release followed by a gradual release over a
12-hour period. This concept was somewhat counterintuitive. Although immediate
release tablets peaked early, conventional wisdom was that the peak plasma
level in a controlled release tablet should occur much later in time, say
between 4 and 8 hours. Previously, the goal had been to keep as much as
possible to a relatively straight line or flat profile.
[71]
After
a number of experiments involving the CONTIN system, all of which failed to
establish a satisfactory dissolution profile, Mr. Oshlack began to use
different retardants and in particular considered an acrylic resin in
combination with a higher aliphatic alcohol. Acrylic resins
are, in essence, Plexiglass. He used the commercial product Eudragit, with
which he was familiar, and which had various compositions.
[72]
He
also worked with organic solvents. They have several disadvantages such as a
low flashpoint and environmental restrictions. That formulation was never
tested.
[73]
These
experiments led to U.S. patent 4,861,598, the AcroContin system, which
uses a combination of an acrylic polymer, such as Eudragit, with a high
aliphatic alcohol to retard the dissolution of pharmaceuticals from 5 to 24
hours. One of the examples was oxycodone. The patent does not specifically
disclose a 12-hour controlled release formulation for oxycodone, or any other
active ingredient, but certainly explains how release may be lengthened or
shortened depending on the amount of retardant used. It does not disclose any in
vivo testing.
[74]
Eventually
he produced a fully aqueous tablet. A single dose bioavailability study was
performed. This formulation eventually became the formulation for the 10 mg
dosage strength marketed by the company.
[75]
During
the prosecution of the ‘598 patent in the United States, Mr. Oshlack
submitted a declaration to which some pages from his lab notebooks were
attached including tablets A12 and A13. Although he had performed in vitro
dissolution testing of those formulations, there had been no in vivo
testing.
GROUNDS OF INVALIDITY
[76]
What
is claimed must be new and useful, and the patent must disclose to those to
whom it is addressed the ways and means to “make, construct, compound or
use it”. Allegations of invalidity, apart from unpatentable subject
matter, such as the Harvard Mouse (Harvard College v. Canada
(Commissioner of Patents) 2002 SCC 76, [2002] 4 S.C.R. 45, 21 C.P.R.
(4th) 417), are grounded in these three broad categories. One may not claim
what one did not invent either because it was previously invented, disclosed,
obvious or because the invention falls short of what was claimed.
[77]
The
well-known allegations of invalidity asserted here - overbreadth, obviousness,
false promise, anticipation, ambiguity, insufficiency, lack of invention, lack
of sound prediction and lack of utility - should not take on separate lives of
their own. They are tied to the specific language of the Patent Act. Nevertheless,
they are useful terms of reference so as to put some order into what might
otherwise be an overwhelmingly amorphous exercise.
Anticipation
[78]
Claims
of a patent are, as said at the outset, invalid if anticipated by prior
disclosure or by prior use. The prior use was within a confidential in vivo
test and so can safely be ignored as not being publicly disclosed.
[79]
Prior
written disclosure was recently considered by the Supreme Court in Plavix,
above, [2008] 3 S.C.R. 265. The Court started with Beloit Canada Ltd. v.
Valmet OY (1986), 8 C.P.R. (3d) 289, where Mr. Justice Hugessen, speaking
for the Court of Appeal, said at page 297:
...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...
[80]
However
in Plavix, Mr. Justice Rothstein, basing himself on more recent U.K.
jurisprudence, held that there are actually two requirements and Beloit was limited
to the first. The first stage is that the prior document must disclose
subject matter which, if performed, would necessarily result in infringement of
the invention. If, and only if, that disclosure requirement is satisfied, there
is a second requirement which is “enablement”, i.e. what may be
required in order to make it work. Mr. Justice Rothstein left open the question
whether enablement for the purpose of anticipation is the same as enablement
for the purpose of sufficiency. In England they are the same.
[81]
Not
one of the prior documents sets out all the information needed to produce the
claimed invention and so it is not necessary to consider what trial and error
might be allowed to get the invention to work. Mr. Oshlack’s efforts established
that the release of oxycodone could be successfully controlled in vitro.
However, the experts agree that although one would not work up an in
vivo testing unless the rate of dissolution fell within certain parameters,
it by no means follows that a promising dissolution profile will lead to
successful in vivo testing. Working the Oshlack disclosure would not
necessarily infringe the ‘738 patent.
[82]
The
fact of the matter is that what was claimed to be invented was not
“described” in any patent or any other publication or used more
than a year before the patent application was filed.
Obviousness
[83]
Even
if not previously disclosed, the invention may have been obvious.
[84]
Again
we not need go much further than the Supreme Court’s decision in Plavix,
above, which clarified the law as to how much effort must go into making the
prior art work before it can be said that the invention was not obvious. Courts
in this and other jurisdictions have considered whether it was “worth a
try” or “obvious to try”. However, the law in Canada is now clear
as Mr. Justice Rothstein said at paragraph 66:
[66] 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.
[85]
He
went on to say:
[67] It will be useful in an obviousness inquiry to follow the
four-step approach first outlined by Oliver L.J. in Windsurfing
International Inc. v. Tabur Marine (Great Britain) Ltd., [1985] R.P.C. 59
(C.A.). This approach should bring better structure to the obviousness
inquiry and more objectivity and clarity to the analysis. The Windsurfing
approach was recently updated by Jacob L.J. in Pozzoli SPA v. BDMO SA,
[2007] F.S.R. 37, [2007] EWCA Civ 588, at para. 23:
In the result I would restate the Windsurfing questions
thus:
(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? [Emphasis added.]
It will be at the fourth step of the Windsurfing/Pozzoli approach
to obviousness that the issue of “obvious to try” will arise.
[86]
We
have identified the notional “person skilled in the art”. Such a
person, or group of persons, knew oxycodone was a pain killer, knew that with co-medicines
it was useful in the relief of mild to moderate pain, knew that as the sole
active ingredient it was useful in the relief of moderate to severe pain, and
that formulations were available to control its release in vitro. Indeed,
enough was known about its properties, such as its half-life elimination from
the body, that it might well be a welcome addition as a controlled release
product, given that many patients react adversely to different opioids.
[87]
The
inventive concept was controlled release oxycodone staying within the
boundaries of a particular dissolution and pharmacokinetic profile from 10 to
14 hours.
[88]
This
combination was different from anything which formed part of the “state
of the art”. The inventive concept was not the idea, but rather getting
it to work. The question therefore is whether these differences constitute
steps which would have been obvious or did they require any degree of
invention.
[89]
Some
cases have conflated the concept of “obvious to try” with
“obvious to work”. However, as Mr. Justice Rothstein stated in Plavix
at paragraph 65: “…I am of the opinion that the “obvious to
try” test will work only where it is very plain or, to use the words of
the Jacob L.J. [in Saint-Gobain PAM
SA v. Fusion Provida Ltd., [2005] EWCA Civ 177], more
or less self-evident that what is being tested ought to work.”
[90]
As
stated earlier, in my opinion it is this combination which is new and useful,
not necessarily any particular part thereof.
[91]
Dr.
Kaiko’s blood plasma profile, Pharmascience says, is simply drawn from
data available from immediate release oxycodone and the fairly early peak in MS
CONTIN. However there were some difficulties with MS CONTIN as in some patients
the blood plasma concentration fell off too soon. Dr. Levy created a
mathematical model which was not dissimilar, to be met with Purdue’s argument
that his was not common general knowledge. As the father of pharmacokinetics,
he was blessed with extraordinary knowledge. Be that as it may, it is not
necessary to reach any conclusion as one had to come up with a formulation
which would achieve that result. It is in this regard that I find the
evidence of Dr. Bodmeier most persuasive. Once it has been decided by
marketing people, clinicians or pharmacokineticists that a controlled release
formulation of a particular drug would be beneficial, the formulator is
provided with a target profile. A first step will be to look at the immediate
release formulation to determine if it would even be possible to make a
controlled release formulation. If the immediate release formulation already
contains a high dose it may not be wise to increase that dosage.
[92]
The formulator has to consider the drug’s solubility,
partition coefficient, polymorphism and other factors. The length of the
drug’s half-life and chemical stability in a solid and in a dissolved
state are most important. If one wants an oral solid dosage form one might
consider tablets, capsules, pellets or granules.
[93]
As to the method of controlled release, if a matrix system
is used there are still a number of choices. Will the matrix formula be water-soluble
(hydrophilic) or water-insoluble (hydrophobic). The list goes on. Once
preliminary formulations have been made they will be tested in vitro
with variations to get a slow, medium or fast profile so as to get an idea of
the release characteristics of the excipients and the drug.
[94]
In Dr. Bodmeier’s opinion:
… there are
numerous choices with respect to the delivery system, excipients and processing,
which a formulator has available for the development of a controlled
release drug delivery system. In addition, each drug is different with respect
to its physicochemical and pharmacokinetic properties. These drug properties
(e.g., dose, solubility, stability, pharmacokinetic, etc.) add to the
complexity of the development process. As said above, there are no set steps
that a formulator can follow in developing a controlled release formulation
with any given drug.
[95]
Given these parameters, and the years of work carried out
by Mr. Oshlack with so many trials and so many errors, I am of the opinion that
it was not self-evident that what was being tried ought to work. There was a
considerable amount of work required to achieve the invention, and the trials
were not routine. The work was inventive.
[96]
In Plavix Mr. Justice Rothstein set out a non-exhaustive
list of factors to be taken into account in determining whether it was
“obvious to try” what is now being claimed:
[69] If
an "obvious to try" test is warranted, the following factors should
be taken into consideration at the fourth step of the obviousness inquiry. As
with anticipation, this list is not exhaustive. The factors will apply in
accordance with the evidence in each 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?
[97]
I have already considered whether it was more or less self
evident that it would work and the amount of effort required. In the light of
my findings, it may not even be necessary to consider motive.
[98]
Although Purdue certainly had motive in that it was
developing a stable of controlled release opioid tablets, there does not appear
to have been much motive within the pharmaceutical industry at large. If
someone cared to think about it, oxycodone was a suitable candidate, but it had
been around for a long time.
[99]
In Apotex Inc. v. Pfizer Canada Inc., 2009
FCA 8, 72 C.P.R. (4th) 141, the Federal Court of Appeal noted that motivation
is treated differently in Canada and in England. Mr.
Justice Noël referred to the decision of Mr. Justice Laddie in first
instance in Lilly Icos Ltd. v. Pfizer Ltd., [2001] F.S.R.
16, affirmed by the English Court of Appeal at [2002] EWCA Civ 1, and
concluded:
[43] The reasoning advanced by Mr.
Justice Laddie and approved by the English Court of Appeal is that where the
motivation to achieve a result is very high, the degree of expected success
becomes a minor matter. In such circumstances, the skilled person may feel
compelled to pursue experimentation even though the chances of success are not
particularly high.
[100] However, Mr. Justice Noël went on to say that an approach based on
the mere possibility that something might work was expressly rejected in Plavix,
above, at paragraph 66, which I quoted earlier.
Sound
Prediction of Usefulness
[101]
Purdue has been criticized for claiming profiles on
compositions containing from about 10 to about 160 mg of oxycodone. Yet, the
range tested in vivo was only 4 mg to 30 mg. It has not proven the
viability of the invention at higher dosages. However, an invention may be
based on “sound prediction”. A prediction may turn out to be
correct, but there may have been no sound basis for making it in the first
place. In effect it was a lucky guess. If so the claim falls. On the other
hand, a prediction may be sound, but later prove to be incorrect. In that case the
claim falls, not because of lack of sound prediction, but rather because the
invention was not useful.
[102]
As stated by Mr. Justice Binnie in Apotex Inc. v.
Wellcome Foundation Ltd., 2002 SCC 77, [2002] S.C.R. 153, (2002)
21 C.P.R. (4th) 499 (AZT) at paragraph 70:
[70] The doctrine of
sound prediction has three components. Firstly, as here, there must be a
factual basis for the prediction.-- Secondly, the inventor must have at the
date of the patent application an articulable and "sound" line of
reasoning from which the desired result can be inferred from the factual basis.--
Thirdly, there must be proper disclosure.
[103]
The factual basis and sound line of reasoning from which
the desired result could be inferred is grounded in the immediate release oxycodone
tablets already on the market which were useful pain killers and which
possessed a particular pharmacokinetic profile. Although these were 10 mg
tablets, Dr. Kaiko was able to predict the characteristics of larger dosages by “partition
coefficient”. For most, but not all, drugs, doubling the dosage would
result in a doubling of the concentration in the blood plasma at any particular
point in time. This would be achieved by multiplying the data for 10 mg dosages
by 16. This is what he did with respect to the peak blood plasma concentration.
However, he also sought a range after 12 hours in which the maximum
concentration might be as much as one-half of the peak level. This variant was
articulate and certainly has not been shown to have been a failure in practice.
Indeed, it is more restrictive than partition coefficients would suggest.
[104]
Pharmascience alleges that claim 11 was made simply to get
around claim 9. It asserts that claim 9 is invalid as it was obvious in the
light of the earlier Oshlack formulation patent in the United
States. In my view that is not the case. Furthermore, even if it
could be said the in vitro dissolution rate in claim 9 was too
broad to give rise to an appropriate in vivo profile, it does not
follow that the same would hold true for the narrower range in claim 11.
Overbreadth
and Lack of Disclosure
[105]
As I said at the outset, this application would be moot had
Purdue not claimed matrixes which could lead to literally hundreds upon
hundreds of different formulations. Yet, according to Pharmascience, it
only disclosed variants of the previously patented AcroContin system. Although
some leeway may be allowed, the invention teaches nothing about the use of HPMC
in a matrix.
[106]
As was said by President Thorson in Minerals Separation
North American Corp. v. Noranda Mines Ltd., [1947] Ex. C.R. 306 at page
352:
By his claims the
inventor puts fences around the fields of his monopoly and warns the public
against trespassing on his property. His fences must be clearly placed in order
to give the necessary warning and he must not fence in any property that is not
his own.
(Cited in Free
World, above, at paragraph 14)
[107]
I quoted part of paragraph 15 of Free World earlier
in these reasons. I now repeat the paragraph in its entirety:
15 In
reality, the “fences” often consist of complex layers of
definitions of different elements (or “components” or
“features” or “integers”) of differing complexity,
substitutability and ingenuity. A matrix of descriptive words and phrases
defines the monopoly, warns the public and ensnares the infringer. In some
instances, the precise elements of the “fence” may be crucial or
“essential” to the working of the invention as claimed; in others
the inventor may contemplate, and the reader skilled in the art appreciate,
that variants could easily be used or substituted without making any material
difference to the working of the invention. The interpretative task of the
court in claims construction is to separate the one from the other, to
distinguish the essential from the inessential, and to give to the “field”
framed by the former the legal protection to which the holder of a valid patent
is entitled.
[108] Pharmascience
relies upon paragraph 32 of Free World, which reads in part:
... As stated, the ingenuity of the
patent lies not in the identification of a desirable result but in teaching one
particular means to achieve it. The claims cannot be stretched to allow the
patentee to monopolize anything that achieves the desirable result. It is not
legitimate, for example, to obtain a patent for a particular method that grows
hair on bald men and thereafter claim that anything that grows hair on
bald men infringes.
[109] In my opinion,
once the dissolution and pharmacokinetic profiles were established by means of
a matrix system, it would be a relatively simple matter to skirt the claims by
putting excipients in a matrix which were not the ones specifically used in the
disclosed examples. Had the inventors worded the claims in such a way that AcroContin
or slight variants thereof were essential, then Pharmascience’s product
would not infringe. This is what happened in Biovail Pharmaceuticals Inc. v.
Canada (Minister of
National Health and Welfare), 2005 FC 9, 37 C.P.R. (4th) 487
in which what might have been a non-essential variant became essential because
the inventors said so. Even without the express language of the claims, there
is a presumption that a non-essential variant falls within its scope. (Free
World, para. 57).
[110] No bargain is
struck for disclosing the invention if it can be worked around by using a
non-essential variant in a matrix.
[111] The question
is whether what is claimed as the monopoly is something which the public
already has. As stated by Professor Vaver in Intellectual Property Law, (Irwin Law, Concord,
Ontario: 1997)
at page 133:
A double
standard operates here. Courts give patents a non-literal "purposive"
construction when they are testing for internal validity or trying to catch
infringers. When testing prior documents for novelty, however, they construe
them narrowly. The documents are then subjected to "the closest
scrutiny," and a "weighty burden" is placed on the challenger.
Sauce for the patent goose should perhaps also be sauce for the prior art
gander. Prior documents should be examined purposively as a skilled reader
would read them. This examination should cover obvious equivalents to described
or claimed elements.
See Shire
Biochem Inc. v. Canada (Minister
of Health), 2008 FC 538, 67 C.P.R. (4th) 94 at para. 60
and following.
[112] I believe the
same approach should be taken with respect to allegations of invalidity on the
grounds of obviousness in the light of the prior art. It is indeed difficult to
apply the fourth step in the Windsurfing/Pozzoli approach, i.e.
“viewed without any knowledge of the alleged invention as claimed
–”.
[113] Furthermore
as stated by Mr. Justice Binnie in Free World at paragraph 25 “It
takes little ingenuity to assemble a dossier of prior art with the benefit of
20-20 hindsight.”
[114] In my opinion
Purdue advanced the state of the art with something that was both useful and
new. It is one thing to try, not knowing if the desired result is achievable.
It is quite another when the path has been shown and it is known that the
result is achievable.
[115] Furthermore,
Purdue did not claim all routes to the desired result. The patent does not prevent
Pharmascience from using other methods to control the release of oxycodone such
as a reservoir or osmotic system, or to use a different in vitro profile
or a different in vivo profile.
[116] Even though
the groundwork had been laid, claims 5 and 11 have advanced the state of the
art. They are an improvement on what was. At paragraph 95 of AZT, above,
Mr. Justice Binnie quoted the London Journal of Arts and Sciences from1831,
which opined that inventors are of three classes. The first are persons of
genius. The second are those whose imagination is not so extensive but who are
capable of making marked improvements. The third class may be made up of those
with small imagination, without any great originality of thought, but who have
a certain ingenuity. I would say this invention falls within the second
category.
CONCLUSION
[117] For these
reasons I would grant the application and prohibit the Minister from issuing a Notice
of Compliance to Pharmascience until the expiry of patent ‘738.
[118] Purdue shall
have its costs. As the Minister did not participate he shall neither be
burdened nor favoured with costs. The parties are aware of recent jurisprudence
which sets out reasonable cost parameters in applications such as these.
Hopefully, they will agree. If not, directions may be sought.
[119] These reasons
were issued on a confidential basis July 16, 2009. The parties have not
requested that any part thereof be redacted for this public version.
“Sean Harrington”
Vancouver,
British Columbia
July
16, 2009
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