Supreme Court of Canada Rules 7-2 Against Patentability of Medical Treatment Methods but Upholds Janssen’s Dosing Regimen Patent

The Supreme Court of Canada (SCC) delivered a significant ruling on Friday, affirming by a 7-2 majority that methods of medical treatment cannot be patented under Canadian law. This decision upholds a legal principle that has governed Canadian patent law for more than half a century. However, the Court simultaneously ruled that a patented dosing regimen developed by Janssen Inc. for its schizophrenia drug INVEGA SUSTENNA is patentable and does not fall within the category of unpatentable medical treatment methods.

The case, Pharmascience Inc. v. Janssen Inc., arose from Pharmascience’s attempt to market a generic version of Janssen’s long-acting injectable drug paliperidone palmitate, used to treat schizophrenia. Janssen holds a patent on specific dosing regimens that schedule the second dose about a week after the initial injection, followed by monthly doses, eliminating the need for daily medication. Pharmascience sought approval for its generic drug, pms-PALIPERIDONE PALMITATE, and argued that Janssen’s dosing regimen patent was invalid because it protected a method of medical treatment, which Canadian law traditionally excludes from patentability.

The Federal Court initially ruled in Janssen’s favor, finding that Pharmascience’s generic product would infringe Janssen’s dosing regimen patent. Pharmascience appealed to the Federal Court of Appeal, which upheld the lower court’s decision. The Supreme Court of Canada then heard the case and dismissed Pharmascience’s appeal, affirming the validity of Janssen’s patent.

Justice Mahmud Jamal, writing for the majority, emphasized that Canadian law has long excluded methods of medical treatment from patent protection. He cited the 1974 SCC decision in Tennessee Eastman Co. v. Commissioner of Patents, which established that patents cannot extend to methods of medical treatment. Although section 41(1) of the Patent Act, which previously barred patents for substances intended for food or medicine except when prepared by specific methods, was repealed in 1993, Justice Jamal clarified that this repeal did not alter the longstanding exclusion of medical treatment methods from patentability.

Justice Jamal explained that the key inquiry is whether the subject matter involves professional medical skill and judgment. He outlined a three-part analysis for courts to determine if a subject matter qualifies as a method of medical treatment: first, whether the subject matter itself amounts to professional medical skill and judgment rather than the use of such skill in selecting it; second, whether the subject matter is tailored to individual patients; and third, whether medical professionals are expected to develop or improve the subject matter. He stressed that these guidelines are not exhaustive and that cases must be decided based on their specific facts.

Applying this test, the Court agreed with the Federal Court’s conclusion that Janssen’s dosing regimens do not require professional medical skill or judgment to implement once prescribed by a physician. Thus, the dosing regimen patent does not constitute a method of medical treatment and is valid.

Justices Michelle O’Bonsawin and Mary Moreau authored a concurring opinion agreeing with the majority that Janssen’s dosing regimen patent is valid but dissenting on the broader principle that methods of medical treatment are inherently unpatentable. They argued that the decades-old precedent from Tennessee Eastman Co. is outdated, relying on a repealed provision of the Patent Act, and that modern statutory interpretation supports patentability of methods of medical treatment, including dosing regimens.

The concurring justices contended that methods of medical treatment should be evaluated under the same patentability criteria as other inventions—novelty, usefulness, and non-obviousness—without a categorical exclusion. They criticized the existing framework as unworkable and inconsistent, advocating for reconsideration of the patentability of medical treatment methods in Canada.