Swiss Claims in Canada

Here's an article by summer student Shaughnessy Hawkins, on Swiss claims, which she published recently on lexology

Swiss claims arose to circumvent restrictions on the patentability of a medicinal use of an already-patented compound. Canadian courts are faced with the difficulty of determining how to interpret such claims, particularly in light of their inherent discrepancy between form and substance. Both European and Canadian courts have recently considered such claims and their legal grounding. A review of these decisions reveals strategic implications for parties considering Swiss claims in the Canadian context, and raises questions about the future treatment of Swiss claims under Canadian law.

Overview of Swiss Claims

Swiss claims are claims of the form “the use of [compound X] in the manufacture of a medicament for the treatment of [disorder Y]” where compound X is previously known. They are therefore (when construed literally) aimed at the manufacture of the substance, rather than the use, thus circumventing any restrictions against patenting a subsequent use.

Swiss claims highlight an ongoing struggle faced by the courts: whether the language of the claims or the substance of the invention should guide the process of construing the claims. By giving weight to the substance of the invention, the court protects the patentee and her idea. By giving weight to the language of the claims, the court protects the public by providing clear notice as to the scope and contents of the patentee’s monopoly. Particularly in the case of subsequent patents involving the same compounds, courts are attuned to the risk of evergreening by a patentee to protect its monopoly.

Canadian Law

What was once a blanket prohibition in Canada against patents for medical uses has softened into a prohibition against patenting methods of medical treatment. The result of such a shift has been that in recent years, use claims have generally been accepted by Canadian courts, provided they do not amount to methods of medical treatment. Hence there is no particular need to use a Swiss claims structure in Canada. Still, such claims exist in many Canadian patents, reflecting international claiming practices.

However, there is more at stake in the Canadian context than mere patentability. Canada has a regime for generic manufacturers seeking entry into the market called the Patented Medicine (Notice of Compliance) or PM(NOC) Regulations, similar to the Hatch-Waxman Act in the United States. Under the PM(NOC) Regulations, a patent containing a claim to the use of a medicinal ingredient is considered eligible for listing under the patent registry, similar to the Orange Book in the US, and the generic company must address the claim prior to gaining entry into the market. In contrast, methods of manufacturing are not eligible for listing and do not need to be addressed. In light of these regulations, what weight should Canadian courts give to the inclusion of the terms “for the manufacture of a medicament useful for…”?

As a general matter, courts have placed increasing emphasis on the specific language used in a patent claim in the past decade. However, interpreting so-called Swiss claims literally would require judges to deliver a potentially hefty blow to patentees, who might then be forced to restructure their claims solely to adapt to Canadian policies. Courts therefore give careful consideration to the issue of dealing with Swiss claims.

Justice Hughes of the Federal Court of Canada recently considered the development of law dealing with Swiss Claims both in Canada and abroad in Merck Co. v. Pharmascience, 2010 FC 510. In this case, he suggested that the treatment of Swiss claims by Canadian courts has been somewhat inconsistent,[1] and pointed to two such cases in support of this fact. However, I would argue that these cases, as well as Justice Hughes’ own decision, are relatively consistent in their approach. When faced with Swiss claims, the courts seem to give greater weight to the substance of the invention, or what is truly being claimed, as opposed to the language of the claim. While the substance of the invention may have been different in each case, leading to different outcomes, the actual approach taken by the judges seems consistent.

For example, in Abbott Laboratories v. Canada (Minister of Health)[2], the Federal Court of Appeal upheld the trial judge’s finding that a claim for “the use of [clarithromycin] Form 0-ethanolate in the preparation of [clarithromycin] Form II for use as an antibiotic” was not a claim for the use of a medicine eligible for listing under the PM(NOC) regulations because the words “for use as an antibiotic” added nothing to the construction. It was well-established that clarithromycin’s only use was as an antibiotic. Hence what constituted the actual invention, or the substance thereof, was the method of preparation of Form II, and this is what guided the court’s interpretation of the claims in this context.

Similarly, in Pfizer Canada Inc. v. Apotex Inc.,[3] Mosley J. found that a claim of the form “the use of a compound of formula (I) […] for the manufacture of a medicament for the curative or prophylactic treatment of an erectile dysfunction in man”, coupled with other claims to various forms of sildenafil in the treatment of erectile dysfunction in man, was directed to the use of the medicine, the manufacture being secondary. This was influenced by the fact that all of the claims described the use of the medicine, while only some referenced the manufacture, leading the judge to read in that the use was the key element of the invention.

In the recent Merck decision, Justice Hughes held that a claim of the form “the use of finasteride for the preparation of a medicament adapted for oral administration useful for the treatment of male pattern baldness in a person and wherein the dosage amount is about 1 mg” was directed to the use of a medicament for treatment of a human condition at a particular fixed dosage, given that the manufacture of the medicament and its use in the treatment of male pattern baldness generally was already well-known. Once again, the judge considered what the inventive concept, or substance of the invention was, and construed the claim in that light.

The Canadian jurisprudence suggests that courts have not considered the Swiss-style structure of a claim to be determinative in the analysis, regardless of the context. Rather, courts have instead considered what has in fact been allegedly invented.

Swiss Claims under European Law

Both the UK Court of Appeal and the Enlarged Board of Appeal of the European Patent Office (the “EBA”) have recently considered the status of Swiss claims under European law. In Britain, the Court of Appeal considered the issue in Actavis UK Ltd. V. Merck Co. Inc.[4] The decision held that Swiss claims are acceptable claims for both new uses as well as new dosage forms of an old compound. The court pointed out that the patent generally does not really teach the manufacture, and may in fact teach how to actually treat a patient. In line with previous jurisprudence on the subject, they held that while a Swiss claim is necessary for the purpose of avoiding the prohibition on claims to the use of medicines, the structure will be ignored when considering issues such as novelty.

Shortly after Actavis was decided, the EBA considered the same issue in Kos Life Sciences.[5] In Kos, the EBA altered their longstanding approach to Swiss claims. Previously, the construction of Swiss claims was considered a necessary and acceptable mechanism to circumvent the prohibition on claims to the use of medicines, though their structure was ignored when considering issues such as novelty. However, the prohibition that gave rise to a need for Swiss claims had since been removed.[6] Given that Swiss claims also lack a connection between what is being claimed and what is in fact novel, the EBA held that, prospectively, such claims will not be read in, i.e., will be construed literally.

Strategic Considerations for Patentees

Canada’s most recent decision on Swiss claims, Merck, considered developments in European patent law, yet gave no suggestion that Canadian law would or should move in a similar direction. However, it may be the case that as Swiss claims come before courts in both Europe and Canada, the Canadian approach may also shift away from reading in the substance of the invention to create more cohesive and predictable treatment internationally. Canadian courts and the Canadian Intellectual Property Office often draw from international treatment of claims in issue. Such a move would also increase predictability in the interpretation of claims in the Canadian courts. Ultimately, it may be the case that as a result of the Kos decision, fewer Swiss claims will be filed abroad, and subsequently in Canada.

Parties filing (or responding to) a Notice of Allegation against a patent containing a Swiss claim should also be attuned to the various characterizations that are possible of such claims and may want to consider addressing multiple such characterizations in the alternative. In Merck, for example, Justice Hughes dismissed Pharmascience’s arguments that the claim was for the manufacture, because the Notice of Allegation had characterized the claims as being for the dosage.

Conclusion

Swiss claims are difficult to construe because their structure often does not reflect the underlying substance of the invention. Canadian courts have tended to emphasize the inventive concept rather than the language of the claim; however, European courts have recently shifted towards a literal interpretation. This may eventually result in Canadian practice conforming with the new European approach. In the meantime, parties considering Swiss claims should bear in mind the possibilities for alternative interpretations under Canadian law.

Shaughnessy Hawkins
Summer Student
Gilbert’s LLP

[1] Merck Co. v. Pharmascience Inc., 2010 FC 510.
[2] (2007), 59 C.P.R. (4th) 1 (F.C.A.).
[3] (2007), 61 C.P.R.(4th) 305 (F.C.).
[4] [2008] EWCA Civ 444, [2009] 1 All E.R. 196 (21st May 2008) [Actavis].
[5] Case No. G 0002/08, 19 February 2010
[6] Article 54(5) of the European Patent Convention now permits purpose-related protection for any further specific use of a known medicament in a method of therapy.