In T2842/18, the Board of Appeal considered the basis required to include a therapeutic effect in a second medical use claim. Whilst the Opposition Division found that the claims met the requirements of Article 123(3) EPC, the Board of Appeal did not agree and rejected the appeal. This decision demonstrates the EPO’s infamously strict approach to added matter and shows how speculative language can cause you problems when amending claims.
When drafting an application, clearly exemplify any therapeutic effects of a compound or composition and avoid speculative language in the examples. If therapeutic effects are speculatively discussed in the examples, include concrete language elsewhere in the description and/or claims.
When determining if a therapeutic use is known from the prior art, check whether speculative language is used around the therapeutic effect in the prior art. If the prior art only speculatively alleges an effect (rather than disclosing in certain terms), then this is not novelty destroying.
There’s no need to consider plausibility of a technical effect when assessing basis for amendments.
Details of the Case
Article 123(2) EPC
Before looking at the at the details of this case in detail, let’s consider the requirements of Article 123(2) EPC, which states:
“The European patent application or European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.”
At the EPO, the “gold standard” set out in G2/10 is used for assessing compliance with Article 123(2) EPC. G2/10 states:
“[A]ny amendment to the parts of a European patent application or of a European patent relating to the disclosure (the description, claims and drawings) is subject to the mandatory prohibition on extension laid down in Article 123(2) EPC and can therefore, irrespective of the context of the amendment made, only be made within the limits of what a skilled person would derive directly and unambiguously, using common general knowledge, and seen objectively and relative to the date of filing, from the whole of these documents as filed …”
In other words, an amendment is not allowable if it presents the skilled person with new technical information.
The claim in question had been amended during opposition proceedings to include the therapeutic effect “for preventing or slowing down the progression in structural joint damage and erosion caused by rheumatoid arthritis…”.
The claim is written as a second medical use claim pursuant to Article 54(5) EPC, meaning that the therapeutic effect is a functional technical feature of the claim. As a consequence, the Board noted that “for the purpose of assessing the requirements of Article 123(2) EPC, it has to be examined whether or not there is a disclosure in the application as filed from which it is directly and unambiguously derivable that this is the effect achieved when the treatment is carried out as claimed.”
A verbatim statement is not enough for basis
The appellant initially argued that the requirements of Article 123(2) EPC were met because there was verbatim basis in Example 3. Example 3 relates to a proposed clinical study to evaluate the efficacy of retreatment with rituximab. Crucially, no results of the proposed study were included in the application. Instead, Example 3 concludes with the statement "[i]t is expected that re-treatment under the protocol herein (or with a different CD20 antibody) will be effective in preventing or slowing down the progression in structural joint damage and erosion caused by RA".
Whilst it was not disputed that there was language for the technical effect in the application, the Board considered that the final statement in Example 3 “does not amount to an explicit disclosure that retreatment ("under the protocol...") does achieve the effect of "preventing or slowing down the progression...", but rather expresses an expectation of what the outcome of the clinical trial might be. It is the board's view that the skilled person would derive from the passage in question that the above mentioned effect might or might not be achieved.”
The Board then went on to consider the final statement of Example 3 in the context of the whole example. The Board noted that 1) Example 3 was a protocol for a proposed clinical study that was yet to be carried out, 2) the main objective of the proposed study was “to evaluate the efficacy of retreatment with rituximab,” and 3) the purpose of the retreatment was to “potentially prevent disease progression”. The Board concluded that in considering Example 3 as a whole the skilled person would not understand that the therapeutic effect was definitely achieved. Instead, the uncertainty expressed in the final statement of Example 3, whether or not the therapeutic effect would be achieved, was confirmed.
As a result, claiming that the therapeutic effect of “preventing or slowing down the progression in structural joint damage and erosion caused by rheumatoid arthritis” is achieved, provides the skilled person with new technical information not disclosed in the application as filed. The Board, therefore, found the claims to add matter.
Plausibility when assessing added matter
The appellant further argued that the requirements of Article 123(2) EPC were met because Example 1 renders the claimed therapeutic effect plausible. Example 1 showed that rituximab significantly inhibits radiographic progression in rheumatoid arthritis patients with an inadequate response or intolerance to one or more THF inhibitors. However, Example 1 did not relate to retreatment with rituximab.
The Board noted that “the criteria for the assessment of direct and unambiguous disclosure of a claimed therapeutic effect are independent of, for example, the presence of data or the assessment of plausibility of the claimed effect. Indeed, there could be direct and unambiguous disclosure of a therapeutic effect that is not plausible at all”, confirming that is it wrong to include considerations of plausibility when assessing added matter.
Petition to Review
The Proprietor has now filed a Petition to Review arguing that the Board applied a consideration of “certainty” as a new standard for assessing direct and unambiguous disclosure under Article 123(2) EPC. According to a recently issued Communication of the Enlarged Board of Appeal, it does not look likely that the Petition to Review will be successful.
If you have any concerns or queries about patent filing strategies, please get in touch with Kate Morgan or your usual Kilburn & Strode advisor.