Background
It is an underlying
principle of patent law that if a product or process, be it a chemical
composition or a method of manufacture or use, is already known, then it
may not be patented. "Knowledge" in this context is anything which has
been put in the public domain anywhere in the world. Therefore, under this
principle, if a chemical compound is known, it would not be possible to
patent the compound itself, even if new properties of that compound are
subsequently discovered.
However, there is a specific
derogation from this requirement for absolute novelty. If an invention
relates to a substance or composition which is to be used in a method of
treatment of a human or animal body by surgery, therapy or diagnosis practised
on that human or animal body then, even if that substance is known, that
knowledge does not prevent the compound from being regarded as new, if
the use of that substance or composition in any such method does not form
part of the state of the art. In other words, it is possible to patent
a known chemical compound as a pharmaceutical provided that it has not
been previously known to have any pharmaceutical activity.
Research tends not to
stop at one pharmaceutical activity and a particular pharmaceutical may,
due to subsequent research, be found to have two or more pharmaceutical
activities. To take an every day example, the drug, Aspirin, was originally
marketed as a drug to alleviate headaches. It was subsequently discovered
also to benefit those suffering from forms of heart disease. The research
which goes into discovering such second medical uses can be enormous and
the results may be no less worthy of patent protection than the original
research which established the first pharmaceutical use. The exemption,
however, does not allow patenting of these products themselves even if
only in relation to treating the new disease.
If the development cannot
be patented then there would be no protection against others using that
finding for their own profit. Without the benefit of patent protection,
new research into further uses of known drugs has less incentive.
The therapeutic use of
that substance cannot be patented either. This is because that use is a
method of treatment of a human or animal body by surgery, therapy or diagnosis
which is practised on that human or animal body.
Methods of treatment are
regarded in Europe as not being capable of industrial application and are
consequently not patentable.
The EPO and the Swiss
Patent Office tackled this problem in the early 1980's, with the Swiss
Patent Office proposing the following solution:
"Use of compound
X in the manufacture of a medicament for the treatment of disorder Y".
At the EPO, the Swiss
claim was rapidly adopted. The Enlarged Board of Appeal held in the EISAI
decision that claims relating to the use of a substance for the manufacture
of a medicament were permitted where the novelty lay in the disease to
be treated even if the manufacturing procedure was not in itself novel
and the active ingredient was known.
The English Courts also
looked at the Swiss type claims in 1985 in the case of Wyeth and Shering
. This case was unusual in that both patent judges, Whitford J and Falconer
J, sat en banc. The traditional English view is that merely indicating
that something is "for" or "suitable for" a new purpose will not give novelty
to subject matter which is already known. However, the Court allowed the
Swiss form of claim to be granted in order to achieve conformity with EPO
practice, although reservations were expressed as to whether or not those
claims could be enforced against alleged infringers.
The Scope of a
Swiss Claim
The Court of Appeal has
now had a chance to look at Swiss claims in infringement proceedings, with
some interesting results.
Monsanto -v- Merck came
before the Court of Appeal on an appeal from a decision to strike out the
allegation that the Swiss claim was infringed. Monsanto alleged infringement
of a patent for a non-steroidal anti-inflammatory drug (NSAID). One common
side-effect of NSAIDs is gastric irritation and the patented class of product
was said to reduce this side-effect.
Although this was a new
chemical class and so protectable per se, the patent also included at claim
20, a Swiss claim. The Swiss claim was in the form:
"Use of a
compound of claim 1 for preparing a medicament for treating inflammation
or an inflammation/associated disorder".
Merck intended to release
a drug in which the active ingredient was known as MK-966. This was a "Keto
form". Monsanto's claim 1 specifically covered the Enol form but not the
Keto form and Monsanto contended that, after the Keto form had been administered
to a patient, a significant amount of the Enol form would be produced.
Moreover, Monsanto claimed that the Enolate form was also covered by the
claim and that an Enolate anion (which produced both the Enol and Keto
forms of MK-966) and the Enol form itself were present during production.
They therefore alleged that claim 20 was infringed and, because a process
claim is also infringed by importing and keeping the direct product of
the process, that the final product also infringed this claim.
The matter came before
Pumfrey J on an application for disclosure of documents (previously called
"discovery") and directions. He questioned whether any disclosure relating
to the manufacturing process was really necessary and suggested that a
strike out application be brought. Pumfrey J felt that this was a clear
case of construction. He stated "the presence of the compound in question
during the course of manufacture of the active ingredient is, accordingly,
in my judgment, not use of the compound in question for preparing the medicament".
In other words, Pumfrey J took the position that a Swiss claim was directed
to the process step of using the active ingredient to make the medicament
and accordingly struck out Monsanto's allegations that Claim 20 was infringed.
The Court of Appeal took
a completely different approach to the construction of the Swiss claim.
The Court of Appeal held that the entire manufacturing process must be
considered. Even if the infringing element was not the active ingredient,
if it had been present at any stage during the manufacturing process, then
there could be infringement. Consequently, the issue as to whether or not
claim 20 had been infringed had to be understood in the context of the
patent as a whole and a view on infringement could only be reached after
the Court had heard the expert evidence and so been able to assume "the
mantle of the man skilled in the art".
Swiss Claims -v-
Methods of Treatment
Due to the fact that the
element of the claim which gives it novelty and inventive step is the new
method of treatment, there is a inherent tension between the Swiss form
of claim and the prohibition in the European patent law against patenting
methods of treatment. This came before the Court of Appeal in Bristol Myers
Squib Co -v- Baker Norton Pharmaceuticals. Bristol Myers' patent related
to cancer treatment drugs. In particular, it related to taxol which is
already known for use in cancer treatment because of it's ability to suppress
cell division. However, this prevention of the replication of cancer cells
also suppresses cell division in bone marrow and leads to the undesirable
side effect of neutropenia. Claim 1 was therefore in the Swiss form but
was expressed as follows:
"Use of taxol
and sufficient medications to prevent severe anaphylactic reactions, for
manufacturing a medicamentation for simultaneous, separate, or sequential
application of from 135mg/m2 up to 175mg/m2 taxol over a period of about
3 hours or less as a means for treating cancer and simultaneously reducing
neutropenia."
Although the claim failed
on issues of novelty and inventive step, the Court of Appeal additionally
found that this was not a Swiss claim but a disguised method of treatment.
Taxol was a known anti-cancer agent and the only point of novelty lay in
the length of time over which the drug was to be administered rather than
in its therapeutic purpose. Moreover, the "manufacturing" process took
place in the hospital pharmacy on a patient by patient basis, and so could
not be considered as "an industrial application" (even if that "manufacture"
was contracted out to a third party). This followed on from their decision
in Monsanto -v- Merck that the Swiss claim is directed to the method of
manufacturing a pharmaceutical.
Moreover, Buxton LJ stated:
"It is important
in this enquiry to remember the emphasis placed by the Board [Enlarged
Board of Appeal in EISAI] on justification by analogy from cases of first
medical use. Recognition of first medical use as a subject of patentability
necessarily entails the use of the substance for a new and completely different
purpose from that in relation to which it is already known. If the Board's
analogy is to hold, therefore, the relationship between the first and the
second medical use must be of the same nature: the second medical use must
be for an end-purpose distinctively different from the first, albeit also
medical, purpose for which the substance was used. That not only follows
from the structure of the Board's argument, but also from the need to respect
the exclusion of methods for treatment from patentability. If the novelty
can lie in the nature of use, rather than in the end-result at which that
use aims, then it is indeed the method of treatment on which patentability
rests."
Therefore Buxton LJ concluded
that Bristol Myers' patent was "an improvement in the method of administering
an existing treatment" rather than a new therapeutic purpose. Further judicial
comment on Swiss claims may be provided shortly. The High Court has recently
been considering Pfizer's Viagra patent. This too contains Swiss claims.
Conclusion
The initial doubts expressed
by Whitford J and Falconer J that, despite granting Swiss claims, they
would never be enforceable has not been borne out by pronouncements of
the Court of Appeal to date.
The Swiss claim is a claim
to a manufacturing process and not merely to the taking of the active ingredient
and converting it into a special medicament. However, the distinguishing
feature of the claim is the use to which that medicament is then put. That
new medical use must be entirely new and cannot just be a modification
of an existing treatment or a better method for treating the disease, for
which the drug is already known to have an effect.
One of the interesting
issues which still remains to be answered with respect to Swiss claims
is that, if the formulation for treating the second medical use is no different
from the formulation for treating the first medical use (i.e. known product
used in old way but with new purpose), then how can a product which may
already have been on the market before the second medical use patent was
filed or the known method by which it is manufactured, now infringe the
later patent? Does the simple act of giving new directions for use either
in the literature accompanying the product or by advertising that this
product has additional capabilities create an infringement? Although, Jacob
J raised this issue in his first instance judgment in Bristol-Myers Squibb
-v- Baker Norton, criticising the EPO for granting claims with no thought
as to how they would be enforced, the Court of Appeal did not comment on
this. However, the existence of the problem has been acknowledged at the
highest level. Lord Hoffman in Merrell Dow -v- Norton8 stated that the
doctrine which requires infringement to be absolute and independent of
the state of the mind of the infringer would "be difficult to apply to
a patent for the use of a known substance in a known way for a new purpose".
However, he did not have to rule on it as the court "was not concerned
with this aspect of the case"! |