By Joanne Chriqui, Scott MacKendrick, Fortunat Nadima, Catherine Thall Dubé and Mathilde Trottier
ROBIC
LAWYERS, PATENT AND TRADEMARK AGENTS
Are methods of medical treatment patentable in Canada? Some say no, others say that they have been since 1987; all struggle on how to tell if a patent even claims a method of medical treatment.
This Friday, the Supreme Court of Canada will weigh in, handing down its decision in Pharmascience v. Janssen.
Context
Central to this question is Canadian Patent No. 2,655,335 (the “335 Patent”), which claims a dosing regimen for the drug INVEGA SUSTENNA, a long-acting injectable formulation of paliperidone palmitate for the treatment of schizophrenia (the dosing regimen teaches the timing of two loading doses, followed by monthly maintenance doses). The question arose from an infringement action brought by Janssen under the Patented Medicines (Notice of Compliance) Regulations (“PM(NOC) Regulations”).
Pharmascience argued that the 335 Patent is invalid for claiming unpatentable subject matter. The Federal Court and the Federal Court of Appeal both disagreed.
Appealing to the Supreme Court against the Federal Court of Appeal decision, Pharmascience advanced two questions:
- Are methods of medical treatment (MMT) patentable in Canada?
- What is an MMT or what test should guide its determination?
Are MMTs patentable?
The Patent Act contains no express prohibition against MMT claims. The Supreme Court’s 1972 Tennessee Eastman[1] decision is the origin of Canada’s historical prohibition on MMTs, and the patent in that case claimed a surgical method for bonding the surfaces of incisions (or wounds) of living tissue through the application of a liquid adhesive compound to one of the surfaces to be bonded.
For Pharmascience, the Tennessee Eastman decision confirmed that MMTs (and other non-economic activities unrelated to commerce, trade or industry) are not patentable in Canada, and Parliament has not decided otherwise since.
Janssen took the opposite view: MMTs have been patentable subject matter for almost 40 years, because the Supreme Court’s decision in Tennessee Eastman was grounded on section 41 of the Patent Act, which section was repealed in 1987. For Janssen, had Parliament intended to exclude MMTs from the definition of “invention,” it would have done so expressly. In the alternative, Janssen argued that the MMT exclusion should be limited to non-economic activities exercised by physicians; and commercial offerings such as drugs, medical devices and their uses (including dosing regimens) should remain patentable.
When does a patent claim a MMT?
On the second question, Pharmascience invited the Court to set up a workable test to determine what is a MMT. Pharmascience proposed a three-pronged test rooted in the Supreme Court’s reasoning in the 1998 Apotex v. Wellcome[2] decision that a patent cannot “fence in” how and when a drug should be used.
Janssen challenged Pharmascience’s proposed test on the basis that it was ambiguous, overbroad and would put Canada out of step with other comparable jurisdictions that recognize novel dosing regimens as patentable.
The Interveners
The Supreme Court heard from five interveners. Of them, only the Canadian Generic Pharmaceutical Association endorsed Pharmascience’s position, reiterating that a prohibition on MMTs was established in Tennessee Eastman and echoing the appellant’s concern that extending patent protection to MMTs would facilitate evergreening and delay access to affordable medication.
In contrast, other interveners were of the view that denying MMTs access to patent protection would stifle research and development. They reiterated Janssen’s argument that Tennessee Eastman was no longer law following the repeal of section 41 of the Patent Act, emphasizing that Parliament has since introduced numerous new protections and regimes, notably the PM(NOC) Regulations, but did not adopt any express exclusion of MMTs. This legislative silence, they submitted, reflects Parliament’s intention that MMTs remain patentable subject matter. Lastly, it was also argued that the Court should not read a MMT prohibition into the Patent Act given the importance of harmonizing Canadian patent law with peer jurisdictions.
The Supreme Court’s decision should address whether the MMT exclusion survives the repeal of section 41 of the Patent Act and, if it does, what test should govern its application. A ruling that adopts Pharmascience’s “how and when” framework could call into question the validity of dosing regimen patents across the pharmaceutical industry. Conversely, a decision endorsing Janssen’s position could effectively close the door on MMT challenges to commercial drug patents in Canada. Either way, the implications for innovators, generics and medical practitioners will be significant.
[1] Tennessee Eastman Co et al. v Commissioner of Patents, [1974] SCR 111, 1972 CanLII 167 (SCC)
[2] Apotex Inc. v Wellcome Foundation Ltd., [1998] FCJ No 382, 1998 CanLII 76101998 CanLII 7610
