https://www.j-platpat.inpit.go.jp/c1801/PU/JP-4376630/15/en
Intellectual Property High Court Case No.10093, 10094 (Gyo-ke) 2023, February 13, 2025 “Agent for Treating Movement Disorders” Case (Presiding Judge Miyasaka)
Excerpts from the Judgment, and Some Considerations
(1) Concerning the threshold for determining whether the cited invention constitutes a “use invention”
“Particularly in the field of medicine, it is often difficult to expect the function and effect from the structure (the chemical substance specified by a chemical formula, etc.), unlike in technical fields of machines, etc., and an invention in the field of medicine is normally completed as a use invention only after verifying the feasibility through time- and cost-consuming processes, such as conducting animal experiments and clinical trials for clarifying the efficacy against the target disease or conducting an experiment that helps to understand that a specific mechanism of action of the chemical substance is closely associated with the efficacy against the target disease. Considering the consistency with this, in order for a cited invention to be recognized as a use invention, it is not sufficient for the substance (agent) relating to the cited invention to merely have a possibility of being put to the target usage, be expected to demonstrate efficacy, or have produced promising results although they are data only for reference obtained in a preliminary trial. It should be said that the cited invention needs to be one for which a person ordinarily skilled in the art would have been able to understand and recognize its feasibility of being put to the target usage, such as that the invention is disclosed with backing by data sufficient for trusting that the substance (agent) is useful for the target usage. Unless such interpretation is adopted, there will be a risk that the novelty and an inventive step of a feasible medicinal use invention that has been completed through the abovementioned processes would be easily denied based on a cited invention that is hardly found to be feasible, and such outcome must be considered unreasonable …”
“(A) First, in Exhibit Ko A3, the trial was conducted as an ‘open trial,’ which is less accurate compared to the ‘randomized, placebo-controlled, double-blind trial’ adopted in Example 1 of the Description. Further, the number of patients who completed the trial is small with nine persons, and the document is only a report consisting of one page in the format of clinical/scientific notes. Therefore, Exhibit Ko A3 lacks detailed statements on the trial method, which would have been naturally stated if it were in the format of a scientific paper (a full paper), and the accuracy of the trial cannot be verified, as it cannot even be identified whether or not a measure was taken to prevent a bias (such as an assumption that the administered drug will work) in patients who participated in the trial, etc., and the document lacks basic information about matters such as how ON time and OFF time were measured. It is difficult to evaluate Exhibit Ko A3 with the abovementioned contents and format (clinical/scientific notes consisting of one page, which only indicates the outline of the trial) to be reliable clinical trial results on its own. Essentially, based on these results, the authors of Exhibit Ko A3 and other researchers would have been expected to proceed to make reports in the format of a scientific paper (a full paper) about trials conducted as to whether or not theophylline has an effect of reducing OFF time in advanced Parkinson’s disease patients, but they have not made such reports. In light of such point, the trial results of Exhibit Ko A3 must be considered insufficient as data that show the abovementioned medicinal usage.”
(2) Concerning an Easily Conceived Property Based on a Main Cited Invention Not Recognized as a “Use Invention”
“Then, naturally, without having to see the results of further experiments and research on theophylline and other adenosine A2A receptor antagonists, Exhibit Ko A3 cannot be regarded to motivate a person ordinarily skilled in the art to the extent of making the usage of the agent of Exhibit Ko 3 Invention the usage of the agent of the Invention.”
(1) Framework for Recognizing Inventive Step in Pharmaceutical Use Inventions:
① The high threshold for recognizing that the Prior Art is complete as a Use Invention
In recognizing the inventive step of a use invention, for the “use” to be a common ground between the prior art and the patented invention, the prior art must be complete as a use invention. If the prior art is not complete as the relevant use invention, the issue becomes whether it would be an easily conceived property to use it for that particular use.
The issue is at what level of completion the cited invention can be considered to have been completed as a “use invention”. This is the point where inventions for pharmaceutical uses and inventions for other uses differ substantially in practice. The court explicitly sets a high threshold, stating that even if tests on humans have been conducted, suggesting efficacy for the intended use, preliminary tests alone are insufficient; disclosure must be supported by data sufficiently reliable to establish that the substance is useful for the intended purpose.
“… in order for a cited invention to be recognized as a use invention, it is not sufficient for the substance (agent) relating to the cited invention to merely have a possibility of being put to the target usage, be expected to demonstrate efficacy, or have produced promising results although they are data only for reference obtained in a preliminary trial. It should be said that the cited invention needs to be one for which a person ordinarily skilled in the art would have been able to understand and recognize its feasibility of being put to the target usage, such as that the invention is disclosed with backing by data sufficient for trusting that the substance (agent) is useful for the target usage.”
(1) Framework for Recognizing Inventive Step in Pharmaceutical Use Inventions:
② The high threshold for determining an “easily conceived property” when the cited invention is not recognized as completed as a Use Invention
The court held that:
“Exhibit Ko A3 … merely encourages implementation of experiments and research … merely states the need for further experiments and research … Then, it cannot be said that a person ordinarily skilled in the art would certainly try so far as to make a medicinal product that adopts KW-6002, beyond experiments and research.”
Namely, the court rejected the so-called “obvious to try” reasoning for recognizing an easily conceived property, and found that there was insufficient motivation to conduct further experiments and research.
Under this framework for recognizing an easily conceived property (motivation), an easily conceived property in medicinal use also necessitates that the cited invention be completed to a level high enough to satisfy the enablement requirement and the support requirement in relation to the targeted medicinal use. This framework is equivalent to the high threshold for recognizing the cited invention as a use invention, as outlined above.
Writer: Hideki TAKAISHI
Attorney at Law & Patent Attorney