Summary

In Pharmascience Inc. v. Janssen Inc., 2026 SCC 26, the Supreme Court of Canada held 7-2 that methods of medical treatment remain unpatentable, and in the same judgment upheld Janssen's patent on a dosing regimen. The deciding question is whether the claimed subject matter amounts to professional medical skill and judgment. For patentees, the practical task is to draft and evidence dosing claims so that, once a physician has chosen the regimen, nothing in it calls for further clinical judgment.

The Event

The Supreme Court released its decision on 17 July 2026 (neutral citation 2026 SCC 26). Justice Jamal wrote for a seven-judge majority and dismissed Pharmascience's appeal. Justices O'Bonsawin and Moreau concurred in the result but would have gone further (Supreme Court of Canada Case in Brief; Canadian Lawyer).

The patent is Canadian Patent No. 2,655,335, owned by Janssen and covering a dosing regimen for INVEGA SUSTENNA, a long-acting injection of paliperidone palmitate for schizophrenia (Torys). According to Canadian Lawyer, Janssen filed the application in 2008 and the patent issued in 2016. Under the regimen, the second dose follows the first by about a week, and later doses are a month apart.

Pharmascience tried to obtain approval for a generic, pms-PALIPERIDONE PALMITATE, in 2020. Janssen sued for infringement. Pharmascience argued the patent was invalid because it claims a method of medical treatment (MMT). The Federal Court (2022 FC 1218) and the Federal Court of Appeal (2024 FCA 23) both rejected that argument (Torys).

The majority confirmed that MMTs are unpatentable because they would monopolize professional medical skill and judgment. It described the "ultimate question" as whether the subject matter amounts to such skill and judgment. It gave three non-exhaustive guidelines (Canadian Lawyer; Torys):

  • Look at whether the claimed subject matter itself amounts to professional skill and judgment, not whether judgment is used to decide if a patient should receive the invention.
  • The more a claim tailors treatment to the individual patient, the more likely it is an MMT.
  • The more medical professionals would be expected to develop or improve the subject matter in their ordinary practice, the more likely it is an MMT.

The majority agreed with the trial judge that "skill and judgment are not required to implement the claimed dosing regimens" once a physician has selected one. It stressed that these cases are "factually suffused" and rejected bright-line rules (Canadian Lawyer).

Context

The bar traces to Tennessee Eastman Co. v. Commissioner of Patents (1974), which relied on former s. 41(1) of the Patent Act. Parliament repealed s. 41(1) in 1993. Both parties asked the Court to overhaul the rule. Janssen argued the prohibition should be abolished because its statutory basis is gone. Pharmascience proposed a test that would invalidate claims directed to "how and when" a practitioner administers a treatment (Torys).

The majority rejected both positions. It held that the prohibition does not depend on s. 41(1). Instead, it applies the principle that professional skills unrelated to trade, industry or commerce are outside the s. 2 definition of "invention" (Torys). Justice Jamal noted that the repeal only removed restrictions on patenting pharmaceutical substances. It did not make treatment methods patentable (Canadian Lawyer).

The concurrence would have abolished the MMT category. In their view, the principles used to identify MMTs are "unworkable, lack internal coherency, and produce inconsistent results," and dosing claims should face the ordinary tests of novelty, utility and non-obviousness (Canadian Lawyer; Torys). Andrew Skodyn of Cassels Brock, who acted for an intervenor but said he spoke for himself, called the majority a "missed opportunity" (Canadian Lawyer).

One consequence of the ruling is a loss of a working distinction. Torys notes that lower courts had treated claims to a specific regimen as patentable and claims to dosing ranges as MMTs. The Supreme Court held that the fixed versus variable distinction is not dispositive. Torys argues this leaves the law less clear, though a trade publication summary (PCKIP) reports the Court confirmed that variable dosage regimes can still be valid.

Implications

The exclusion operates as a validity ground. It was raised here by a generic company defending an infringement action over a granted patent, and the Court assessed the claims as granted. The risk therefore sits with patents already issued and with applications still being drafted. It binds the claim, whoever is accused of infringing it.

For patentees and drafters, Torys identifies two features that strengthen a dosing claim: the regimen applies to a class of patients without individual adjustment, and any flexibility in timing, dose or administration can be shown not to need clinical judgment. Practical steps:

  • Draft for implementation, not selection. The Court separated the physician's decision to use the regimen from the regimen's own content. Claim fixed timings and doses for a defined patient class, so the claim tells the physician what to do.
  • Audit variable language. Phrases such as "as determined by the physician" or open dose ranges invite the argument that the claim hands the choice to clinical judgment. Review pending and granted claims for them.
  • Build the evidence file. The Court called the inquiry fact-dependent and tied to how the regimen is meant to be applied. Keep trial design records, label text and expert evidence showing the regimen works as written without individual tailoring. Janssen's "extensive research and trials" background fits this pattern (Supreme Court Case in Brief).
  • Keep fallback claims. Since no bright line exists, pair broader range claims with narrower fixed-regimen claims.

For challengers, Torys notes that invalidity remains available where a claim in substance requires or monopolizes professional judgment. A challenger cannot argue that dosing, timing or administration instructions are excluded as a category. Build the attack on evidence of individualized tailoring and on what physicians already do in practice.

Korea and Asia angle. None of the sources involves a Korean or Asian party or office, so the relevance is indirect. Korean originator companies that file or hold Canadian dosing and formulation patents sit on the patentee side of this rule. The same companies, when developing generics or biosimilars for Canada, sit on the challenger side. A portfolio team should review Canadian dosing claims defensively and, for products under development, assess third-party dosing patents against the three guidelines rather than assuming a dosing claim is invalid.

Outlook

The majority left the test open and fact-specific, so the next signals will come from the Federal Court and Federal Court of Appeal applying the three guidelines to claims that include ranges, titration steps or patient-specific adjustment. The concurrence also shows two of nine justices ready to reconsider the category. The sources report no legislative proposal, and a change would have to come from a future case or from Parliament.

While that develops, hold a hedge. For Canadian applications in pending prosecution, consider filing a fixed-regimen claim set alongside any range claims, so that a loss on the broader claims does not take the whole family. For granted dosing patents that are likely to be asserted, assemble the implementation evidence now, before a challenger frames the dispute. For anyone preparing a clearance or invalidity opinion on a Canadian dosing patent, treat earlier advice based on the fixed versus variable distinction as outdated and re-run it under the 2026 SCC 26 guidelines.

Sources