Key points
- In this opposition appeal, claim 1 is directed to tapentadol for use in the treatment of irritable bowel syndrome. The starting point for inventive step is D4 which relates to tapentadol and its confirmed efficacy in animal models of visceral pain. “While D4 does not specifically refer to IBS, visceral pain is a typical manifestation of IBS, the therapeutic indication named in claim 1 of the patent in suit.”
- The patentee argued that “a drug developer would typically seek to provide a suitable drug for a given medical indication rather than investigate further medical indications for a given drug. As the objective technical problem formulated [by the Board] did not reflect reality document D4 could not be considered an eligible starting point for the assessment of inventive step. Moreover, this technical problem did not correspond to the problem stated in the patent in suit”
- The Board is not convinced. “In fact, either approach may be taken by a person skilled in the art, depending on the stages reached in the development and life of a drug compound and the rationale for its development. After the initial stage of drug discovery, the suitability of the drug for different therapeutic uses may conceivably be explored.”
- I.e, a person skilled in the art may either “seek to provide a suitable drug for a given medical indication” or “investigate further medical indications for a given drug”, “depending on the stages reached in the development and life of a drug compound” (and presumably this is a non-exclusive OR).
- I think this conclusion of the Board could be quite important in the pharma field.
- “The objective technical problem as established starting from the teaching of D4 is thus realistic: It reflects the task the skilled person would have faced after the initial development of tapentadol.”
- “there would have been no hindsight involved in considering IBS as a possible field of application for a drug effective against visceral pain.”
T 2443/18 -
https://www.epo.org/law-practice/case-law-appeals/recent/t182443eu1.html
Summary of Facts and Submissions
I. European patent No. 2 588 093 (patent in suit) was granted with a set of eight claims. Claim 1 reads as follows:
"1. Tapentadol for use in the treatment of irritable bowel syndrome."
The remaining claims 2 to 8 are dependent claims.
II. The patent was opposed under Article 100(a) EPC on the grounds that the claimed subject-matter lacked novelty and did not involve an inventive step.
III. The documents cited in the proceedings included the following:
D1: Drugs of the Future 31(12), 1053-1061 (2006)
D3: J Clin Gastroenterol 35(Suppl), S58-S67 (2002)
D4: Neurology 70(Suppl 1), A164, P03.157 (2008)
IV. The decision under appeal is the opposition division's decision rejecting the opposition, announced on 13 June 2018 and posted on 23 July 2018.
V. According to the decision under appeal, the subject-matter of claim 1 as granted was novel. It also involved an inventive step: Prior-art document D3 taught that loperamide was a compound suitable for the treatment of irritable bowel syndrome (IBS). Loperamide, like tapentadol, belonged to the class of my-opioid receptor agonists. Starting from D3 as the closest prior art, the technical problem to be solved consisted in providing an alternative my-opioid receptor agonist useful for the treatment of IBS. This problem was credibly solved by claim 1 of the patent in suit in view of the experimental data on tapentadol presented in examples 1 and 2. The person skilled in the art would not have found any indication in the cited prior-art documents that tapentadol, instead of loperamide, could be successfully used in the treatment of IBS.
VI. The opponent (appellant) appealed this decision.
VII. Oral proceedings before the board were held on 9 April 2021.
VIII. The appellant's [opponent's] arguments on inventive step may be summarised as follows.
Document D4, which disclosed the efficacy of tapentadol in several animal models of visceral pain, was a promising starting point for the assessment of inventive step. The objective technical problem was to provide a further medical use of tapentadol.
It was known (e.g. from document D3) that visceral pain was a major symptom of IBS. There was no relevant distinction between visceral pain and visceral pain in IBS. The animal models mentioned in D4 included those relied on in the examples of the patent in suit in support of the efficacy of tapentadol in the treatment of IBS. No inventive skill would thus have been required to suggest tapentadol for treating IBS.
IX. The respondent's arguments on inventive step may be summarised as follows.
source http://justpatentlaw.blogspot.com/2021/06/t-244318-i-drug-development.html
