On July 17, 2026, the Supreme Court of Canada released its long-awaited decision in Pharmascience Inc. v. Janssen Inc., 2026 SCC 26 (“Pharmascience SCC”),[1] which dismissed Pharmascience’s appeal and upheld the validity of Janssen’s Canadian Patent No. 2,655,335 (“335 Patent”), which relates to dosing regimens for long-acting injectable paliperidone palmitate formulations for treatment of schizophrenia and related disorders (marketed by Janssen in Canada under the brand name INVEGA SUSTENNA®).
The seven-judge majority decision per Jamal J. (Wagner C.J. and Karakatsanis, Côté, Rowe, Martin and Kasirer JJ. concurring) confirmed that methods of medical treatment remain unpatentable subject matter under Canadian law and that this has been settled law for more than half a century, since the Supreme Court last directly considered the patentability of methods of medical treatment in Tennessee Eastman Co. v. Commissioner of Patents, decided in 1972, [1974] S.C.R. 111 (“Tennessee Eastman”). The two-judge joint concurring reasons (per O’Bonsawin J. and Moreau J.) expressed the view that methods of medical treatment (including dosing regimens) can qualify as patentable subject matter and that a prohibition on the patenting of methods of medical treatment should no longer exist given their view that the legal foundations of Tennessee Eastman had been eroded and its reasoning was no longer applicable.[2]
The majority decision largely preserves the status quo: claims to methods of medical treatment remain unpatentable and the “professional skill-and-judgment” inquiry governs this determination, including for claims to dosing regimens.
Historically, the Federal Court and the Federal Court of Appeal applied the unpatentability of methods of medical treatment in the context of drug-dosing regimens through what sometimes operated as a distinction between fixed versus ranged/variable dosage regimens or administration intervals. As noted by the Federal Court at para. 164, “claims restricted to particular dosages and specific administration schedules have been found to be patentable subject matter, where the amounts and timing are fixed… whereas claims to dosages or schedules with ranges within which the physician must exercise skill and judgment have been found to not be a vendible product and thus not patentable”.[3] However, the Federal Court of Appeal rejected any categorical distinction between fixed versus ranged/variable dosage regimens and iterated that the proper inquiry remains whether the use of the invention requires the exercise of skill and judgment.[4]
The Supreme Court upheld the Federal Court of Appeal’s decision, holding that the focus does not turn on such a bright line rule between fixed versus ranged/variable dosage regimens, but rather, the question is whether the claims amounts to professional skill and judgment. The Court noted that whether the patent claims fixed versus variable dosing is, at best, an evidentiary proxy that is “sometimes useful but never dispositive of whether the claims are for unpatentable methods of medical treatment”.[5]
The Supreme Court’s decision addresses the uncertainty in the law governing methods of medical treatment, particularly whether the patentability of dosing regimens is asserted to turn on a distinction between fixed and ranged/variable dosing.[6]
The 335 Patent
The 335 Patent, “Prolonged-Release Injectable Suspensions of Paliperidone Palmitate and Dosage Forms and Delivery Systems Incorporating Same”, was filed in Canada on December 17, 2008 (claiming priority to a U.S. application filed December 19, 2007) and issued on September 6, 2016.
The 335 Patent relates to dosing regimens for long-acting injectable paliperidone palmitate formulations for the treatment of schizophrenia and related disorders and teaches a dosing regimen that achieves an optimum blood plasma concentration-time profile. The inventors targeted a plasma concentration exposure range of 7.5 to 40 ng/mL of paliperidone to ensure efficacy and minimize adverse side effects. To rapidly achieve therapeutic blood plasma concentrations, the patent teaches a “loading dose” regimen – specific doses administered on Day 1 and Day 8 (±2 days), followed by monthly (± 7 days) “maintenance doses”.
The 335 Patent has 63 claims, which the Federal Court divided into the following four sets: (1) prefilled syringes adapted for administration (claims 1-16); (2) use of a dosage form (claims 17-32); (3) use of paliperidone palmitate in the manufacture or preparation of a medicament (claims 33-48); and (4) dosage forms adapted for administration (claims 49-63).[7] The Federal Court held that claims 1 to 16 and 33 to 63 claimed vendible products and therefore were not methods of medical treatment. The method of medical treatment analysis focused on only claims 17 to 32 (i.e., the use claims).[8]
Each of the claims relates to the following claimed dosing regimen: loading doses on day 1 (150 mg-eq.; 100 mg-eq. for renally impaired patients) and day 8 (±2 days) (100 mg-eq.; 75 mg-eq. for renally impaired patients), followed by monthly maintenance doses (±7 days) (75 mg-eq.; 50 mg-eq. for renally impaired patients). All of the claims incorporate one these dosing regimens.
The paliperidone palmitate – 335 Patent litigation in the Federal Courts
The 335 Patent has been the subject of several proceedings before the Federal Court and the Federal Court of Appeal involving Teva, Pharmascience and Apotex, which are summarized below.
| Proceeding | FC decision | FCA decision | Issue(s) | Result |
| Janssen v. Teva | 2020 FC 593 | 2023 FCA 68 | Obviousness; infringement or induced infringement | FC: claims not obvious, but inducement not established FCA: appeal on obviousness dismissed; cross-appeal allowed – Teva would induce infringement |
| Janssen v. Pharmascience; Janssen v. Apotex | Pharmascience: 2022 FC 62 Apotex: 2022 FC 107 | Pharmascience: 2024 FCA 10 Apotex: 2024 FCA 9 | Pharmascienc’s motion for summary trial (re: non-infringement) Apotex’s motion for summary trial (re: non-infringement) | FC: inducement established — product monographs would influence prescribers to infringement FCA: affirmed FC SCC denied leave to appeal in both the Pharmascience and Apotex cases. |
| Janssen v. Pharmascience (re: validity) | 2022 FC 1218 | 2024 FCA 23 | Obviousness; unpatentable subject matter (i.e., methods of medical treatment) | The subject of the Supreme Court decision. FC: claims not obvious and not directed to methods of medical treatment. FCA: affirmed (methods of medical treatment the sole issue). |
| Janssen v. Apotex (re: abuse of process) | 2023 FC 912 | 2023 FCA 253 | Janssen’s motion for summary judgment (re: invalidity-only) | FC: Janssen’s summary judgment motion dismissed in light of prior Janssen v. Apotex case (re: infringement). FCA: reversed – Apotex’s invalidity defences constituted an abuse of process and summary judgment was granted. |
The case which was ultimately determined by the Supreme Court is the Pharmascience case (2022 FC 1218, aff’d 2024 FCA 23). In the Federal Court decision, Manson J. rejected Pharmascience’s allegations of invalidity of the 335 Patent for obviousness and unpatentable subject matter (i.e., method of medical treatment). Regarding the method of medical treatment issue, Manson J. held that professional skill and judgment were not required to practise the claimed dosing regimens (i.e., the invention as claimed): a physician can choose to prescribe the claimed treatment or depart from it and thereby not practise the claimed invention.[9]
The Federal Court of Appeal (per Locke J.A.) held that the fixed versus range/variable dosing dichotomy does not determine per se patentability. Rather, “[t]hough a fixed dosage and schedule may be a good indication that no such skill and judgment would be required, evidence may indicate otherwise”. The proper inquiry was thus held to be whether professional skill and judgment would be required in practising the claimed invention.
The Supreme Court’s decision
Leave to appeal to the Supreme Court was granted on September 19, 2024, and the appeal was heard on October 9, 2025.
The Majority Reasons – Maintaining the Status Quo
Writing for the seven-judge majority, Jamal J. dismissed the appeal. The majority confirmed that methods of medical treatment remain unpatentable. In doing so, the majority rejected Janssen’s invitation to do away with considering methods of medical treatment as unpatentable subject matter and held that nothing turns on parsing Tennessee Eastman. The majority noted that the repeal of former s. 41(1) of the Patent Act did not transform methods of medical treatment into patentable subject matter. It merely removed restrictions on patenting pharmaceutical substances, as part of broader reforms to the compulsory-licensing scheme. Nothing in the text, debates, or commentary suggested any parliamentary intent to overrule Tennessee Eastman.[10]
Canadian law has consistently treated methods of medical treatment as unpatentable because they amount to the exercise of professional skill and judgment, which, unlike subject matter relating to trade, industry or commerce, does not respond to the incentives of the patent bargain.[11] The prohibition rests on this principle, as recognized in Shell Oil Co. v. Commissioner of Patents, [1982] 2 S.C.R. 536 (“Shell Oil”) and Apotex Inc. v. Wellcome Foundation Ltd., 2002 SCC 77, [2002] 4 S.C.R. 153 (“Wellcome”), reflected across the jurisprudence, and confirmed by purposive interpretation of section 2 of the Patent Act. Parliament’s silence following the repeal of former s. 41(1) of the Patent Act is explained by this consistent judicial interpretation since Tennessee Eastman.[12]
This position is also consistent with the administrative position taken in the Manual of Patent Office Practice[13] and the scholarly literature.[14] Canada’s decision not to legislate an express exclusion – as other TRIPS signatories, such as the United Kingdom, have done – is of no significance because none was needed.
The majority also addressed the incentive rationale for excluding professional skill and judgment from being patentable. Professionals are already under ethical obligations to exercise their skill for their patients’ best interests and to share those skills widely; they neither need, nor should receive patent protection (i.e., a monopoly) to do so.[15] Also, it is not the role of the patent system to regulate professionals in the exercise of their professional skill and judgment or to permit them to fence in such skills to extract monopolistic patent profits.[16]
The majority rejected the tests proposed by both parties as extreme.[17] Pharmascience urged the adoption of the approach from Wellcome, under which a claim is an unpatentable method of medical treatment if it claims “how and when” a drug should be administered.[18] The majority declined to adopt it, stating that Wellcome did not establish a “how and when” test for a method of medical treatment and the test would have produced the opposite result in Wellcome itself.[19]
The majority agreed with the Federal Court of Appeal and adopted a “balanced approach” that distinguishes the exercise of professional skill and judgment from other medical innovations.
The “ultimate question” is whether the claimed subject matter amounts to professional medical skill and judgment or, stated differently, whether it seeks to “‘fence in’ an area of medical treatment”.[20]
The analysis framework set out by the majority begins with purposive construction of the claims and is applied to determine the “real subject matter of the claim,” regardless of how the claim is drafted. As noted by the majority, drafting a claim in product form does not necessarily make its subject matter a vendible product; focusing on form over substance would be an error.[21]
Three guiding considerations were also set out. First, the focus is on whether the subject matter of the claimed invention amounts to professional medical skill and judgment, not whether professional medical skill and judgment would be applied in selecting the claimed invention for a particular patient or use.[22] Second, the more the subject matter is tailored to individual patients, the more likely it engages professional skill.[23] Third, the more medical professionals are expected to develop or refine the subject matter in its use, the more likely it crosses the line to being a method of medical treatment (which is unpatentable subject matter). These considerations are expressly non-exhaustive and establish no bright line rules; methods of medical treatment cases are factually suffused and fall to the expertise of the Federal Courts.
Applying this framework, the majority found no reviewable error below. The trial judge correctly focused on professional skill and judgment: none is required to implement the claimed regimens once a decision has been made to use the product for the claimed purpose and, accordingly, the claims do not monopolize the physician’s professional skill and judgment.
The Concurring Reasons: Time to Set Aside Tennessee Eastman
O’Bonsawin and Moreau JJ., writing separately, agreed that the 335 Patent is valid, but would have reached that result by discarding the prohibition against methods of medical treatment entirely. According to O’Bonsawin and Moreau JJ., Tennessee Eastman’s ratio that methods of medical treatment are unpatentable hinged on the now-repealed s. 41(1) of the Patent Act (they wrote that it is “incontrovertible that s. 41 was the central guidepost”). They concluded that the principles developed to identify methods of medical treatment are unworkable, lack internal coherency, and produce inconsistent results.[24] In their view, “a modern interpretation of the Patent Act compels the conclusion that [methods of medical treatment] are not inherently unpatentable.”[25]
In contrast with the majority, the concurring judges concluded that, on a modern interpretation of the Patent Act, methods of medical treatment (including dosing regimens) can qualify as patentable subject matter.[26] Rather than a blanket prohibition against methods of medical treatment, such claims should face the same rigorous screens as any other invention: if the subject matter falls within the s. 2 definition of “invention” and is new, useful, and non-obvious, a patent should issue.
Instead of a policy-based prohibition against the monopolization of professional skill and judgment, the concurring judges reasoned that concerns about subjective human judgment are better addressed through the utility requirement. In their view, an invention that depends on an operator’s judgment or reasoning may lack reproducibility and, consequently, utility. A complex surgical or medical method requiring subjective judgment could therefore remain unpatentable, not because of a categorical subject matter exclusion, but because its promised result cannot be reliably reproduced.[27]
They acknowledged that this will often overlap with the majority’s skill and judgment test in outcome, but they anchored their analysis in “established doctrine, rather than a hindsight assessment of whether a medical decision involves varying degrees of skill and judgment”.[28]
Does the Supreme Court’s Majority Decision Change Anything?
The professional skill and judgment test remains: For brand and generic pharmaceutical manufacturers alike, the practical headline is that methods of medical treatment continue to be unpatentable subject matter. The relevant inquiry is whether practising the claimed invention requires the exercise of professional skill and/or judgment.
No bright line test for method of medical treatment: Dosing regimens, whether fixed or ranged/variable, can constitute patentable subject matter. The fixed versus ranged/variable dosing regimen distinction is no longer dispositive, though it remains a potentially useful evidentiary proxy for whether the claim is an unpatentable method of medical treatment. That question relates to the degree of individualization involved, which is helpful but not determinative. The Court’s refusal to adopt a bright line rule suggests that patentability will continue to be assessed on a case by case basis. Claims for dosing that is individualized will remain particularly vulnerable and expert evidence will be critical.
No adoption of either party’s test: Doctrinally, the decision is notable for what the majority declined to do. The majority did not abolish the prohibition against patenting methods of medical treatment, as Janssen primarily invited and as three interveners urged. The majority also did not adopt Pharmascience’s proposed “how and when” test, steering instead to the balanced approach of the Federal Court of Appeal.[29]
No economic/non-economic distinction: The majority was equally unpersuaded by Janssen’s proposed test, under which the prohibition would be confined to “non-economic” medical activities – a focus the majority found “unhelpful” because the treatment of patients by a medical professional will always have economic value. The point has always been to distinguish the skill and judgment of medical professionals from a “vendible product” that responds to the economic activity spurred by patent protection.[30] Janssen’s test would also have made every dosing regimen patentable as a “commercial offering,” contrary to the jurisprudence holding some regimens to be unpatentable, and would have dramatically expanded patent protection for medicines, which would substantially disrupt commercial expectations in the marketplace.[31]
Evergreening remains a double patenting issue: The majority was also careful to distinguish the prohibition against patenting methods of medical treatment from concerns about double patenting or evergreening. Pharmascience argued that its proposed “how and when” test reflected sound public policy because it would help prevent the evergreening of pharmaceutical patents. The majority rejected that justification, holding that the approach to methods of medical treatment should not be distorted to address those “conceptually distinct concerns.” Improper evergreening is instead addressed through the rules against double patenting.[32]
Substance over form – lessons for claim drafting: The decision also carries lessons for claim drafting. Claim form alone will not determine patentability: drafting a claim in product form or with a specific dosing schedule does not necessarily make its subject matter patentable as a “vendible product”.[33] What matters is the substance of what is claimed. The clearest guidance from the Supreme Court’s majority is that the more the claimed subject matter involves tailoring treatment to a patient’s particular circumstances, the more likely it is to be the exercise of professional medical skill and judgment. Patent drafters should keep these principles in mind when claiming subject matter that physicians may be expected to develop or refine in the ordinary course of treating patients.
Conclusion
The majority decision of the Supreme Court sets out a bare analytical framework, without drawing a definitive boundary between patentable medical innovations and unpatentable methods of medical treatment (i.e., the exercise of professional skill and judgment). That boundary will continue to be developed case by case, through purposive claim construction and evidence concerning how the claimed subject matter is applied in medical practice.
[1] Janssen Inc. v. Pharmascience Inc., 2022 FC 1218, aff’d 2024 FCA 23, aff’d 2026 SCC 26.
[2] Pharmascience SCC, para. 129, 144–145.
[3] Janssen Inc. v. Pharmascience Inc., 2022 FC 1218 at para. 164.
[4] Janssen Inc. v. Pharmascience Inc., 2024 FCA 23 at para. 37.
[5] Pharmascience SCC, para. 105.
[6] Cobalt Pharmaceuticals Co. v. Bayer Inc., 2015 FCA 116 at para. 101; Hospira Healthcare Corp. v. Kennedy Trust for Rheumatology Research, 2020 FCA 30 at paras. 51-53.
[7] Janssen Inc. v. Pharmascience Inc., 2022 FC 1218 at para. 34.
[8] Pharmascience SCC, para. 14.
[9] Janssen Inc. v. Pharmascience Inc., 2022 FC 1218 at paras. 170–171.
[10] Pharmascience SCC, paras. 70-71.
[11] Pharmascience SCC, paras. 56 and 86.
[12] Pharmascience SCC, para. 76.
[13] Pharmascience SCC, para. 66.
[14] Pharmascience SCC, para. 67.
[15] Pharmascience SCC, para. 59.
[16] Pharmascience SCC, para. 60.
[17] Pharmascience SCC, para. 88.
[18] Pharmascience SCC, para. 81.
[19] Pharmascience SCC, paras. 82-83.
[20] Pharmascience SCC, paras. 88-89.
[21] Pharmascience SCC, paras. 90-91.
[22] Pharmascience SCC, paras. 93-94.
[23] Pharmascience SCC, paras. 95-96.
[24] Pharmascience SCC, paras. 128, 143-145, 162, 267.
[25] Pharmascience SCC, para. 267.
[26] Pharmascience SCC, paras. 233-267.
[27] Pharmascience SCC, paras. 270-281.
[28] Pharmascience SCC, para. 282.
[29] Pharmascience SCC, para. 88.
[30] Pharmascience SCC, para. 86.
[31] Pharmascience SCC, para. 87.
