7.2.3 Evidence of therapeutic effect
Post-published evidence may be taken into account, but only to back up the findings in the application in relation to the use of the compound(s) as a pharmaceutical (T 609/02, T 950/13).
If the description in a patent specification provides no more than a vague indication of a possible medical use for a chemical compound yet to be identified, more detailed evidence cannot be used later to remedy the fundamental insufficiency of disclosure of such subject-matter (T 609/02). Where the therapeutic effect is a functional technical feature of the claim, the application must disclose the suitability of the product to be manufactured for the claimed therapeutic application and evidence filed later cannot be used to remedy a fundamental insufficiency of disclosure (point established in T 609/02, as summarised in T 1045/13).
In G 2/21, the Enlarged Board summarises this case law (primarily T 609/02) and then lists a series of decisions in line with T 609/02 while reiterating the main reasons (points 75 to 77 of the Reasons). Among these principles, G 2/21 states that in order to meet the requirement that the disclosure of the invention be sufficiently clear and complete for it to be carried out by the person skilled in the art, the proof of a claimed therapeutic effect has to be provided in the application as filed, in particular if, in the absence of experimental data in the application as filed, it would not be credible to the skilled person that the therapeutic effect is achieved. A lack in this respect cannot be remedied by post-published evidence.
Since the case law on this point prior to G 2/21 has been confirmed, it remains applicable. At the end of each section, decisions following G 2/21 are specifically highlighted first, confirming that post-published evidence cannot remedy an initial lack of disclosure.
Referring to T 609/02, the board in T 433/05 recalled that where a therapeutic application was claimed in the Swiss-type form, attaining the claimed therapeutic effect was a functional technical feature of the claim. As a consequence, under Art. 83 EPC 1973 the application had to disclose the suitability of the product to be manufactured for the claimed therapeutic application (see also T 1685/10). Note, however, that according to G 2/08 date: 2010-02-19 (OJ 2010, 456), where the subject-matter of a claim is rendered novel only by a new therapeutic use of a medicament, such claim may no longer have the format of a so-called Swiss-type claim as instituted by decision G 5/83 (OJ 1985, 64). Following T 609/02, the board in T 801/06 recalled that a claimed therapeutic effect may be proven by any kind of data as long as they clearly and unambiguously reflect the therapeutic effect. Thus, the fact per se that the experiments in the patent were not carried out with a "real" metastasis was not sufficient to deny sufficiency of disclosure.
In T 2571/12 (treatment of schizophrenia with glutathione), the board stated that there was no evidence at all either in the patent or in the available prior art for a therapeutic effect of glutathione precursors for any of the claimed disorders, and hence the post-published document, allegedly supporting such an effect inter alia for bipolar disorders, likewise could not been taken into account for the assessment of sufficiency of disclosure.
In T 1045/13, concerning a second medical use claim worded in accordance with Art. 54(5) EPC, the board stated that the application as filed did not provide any indication of the principle underlying the relationship between the activity of the pharmaceutically active agent, i.e. the NGF, and the therapeutic effect, i.e. the alleviation of the symptoms of the psychological conditions claimed. The description did not provide any information on the mechanism of action of NGF. No background references were cited that linked NGF to the therapeutic effects to be obtained, and no in vitro assays were provided to illustrate any such effect. In the complete absence of such information, the experimental evidence on file was of decisive importance. But the evidence in the application as filed did not constitute a sufficient disclosure. Indeed, the experimental evidence consisted of eleven examples relating to various conditions but did not cover all the conditions defined in claim 1; each example related to a single patient only, contrary to the common practice in order to allow statistical analysis of the results. Also, in the absence of a control group, placebo effects could not be excluded. The post-published evidence might be taken into account, but only to back up the findings in the patent application. Post-published evidence could not establish sufficiency of disclosure on its own. They did not need therefore to be discussed. For sufficiency of disclosure, it is not relevant what the respondent (patent proprietor) was aware of, but decided not to disclose.
Decisions since G 2/21 confirming that post-published evidence cannot remedy an initial lack of disclosure. For example (key points stated in brackets): T 1779/21 (therapeutic effect was not credible; post-published data was not taken into account ; T 2790/17 (even though experimental data was provided in the application as filed, the therapeutic effect was not credible so that post-published evidence could not be taken into account) ; T 197/22 (a lack of sufficiency of disclosure cannot be remedied by post-published evidence – the patent proprietor's argument relying on the post-published document D39 was therefore not persuasive) ; T 166/22 (there were serious doubts substantiated by verifiable facts; post-published evidence D24 was therefore not taken into consideration); T 853/22 (the effect not credibly disclosed could not be remedied by post-published document D8).
In T 552/22 the lack of disclosure could not be remedied by post-published evidence and the board specified that the right to be heard did not entail the right to have post-published evidence considered.
- T 0867/23
In T 0867/23 the board decided on the basis of the patent as granted (main request). Claim 1 was worded as a purpose-limited product claim in accordance with Art. 54(5) EPC. The treatment of "primary negative symptoms of schizophrenia" was a functional feature of claim 1.
The parties were in dispute regarding whether the application as filed made the claimed therapeutic effect plausible, and whether post-published evidence could be taken into account. The question was whether, on the basis of the evidence contained in the application as filed, cariprazine was demonstrated to have the claimed therapeutic effect on primary negative symptoms of schizophrenia.
In support of its reasoning, the board cited G 2/21 (point 77 of the Reasons), in which the Enlarged Board had explained that, in order to meet the requirement of sufficiency of disclosure, "[…] the proof of a claimed therapeutic effect has to be provided in the application as filed, in particular if, in the absence of experimental data in the application as filed, it would not be credible to the skilled person that the therapeutic effect is achieved. A lack in this respect cannot be remedied by post-published evidence..
In the board's view, this statement of the Enlarged Board did not set a new standard for reliance on post-published evidence in the context of sufficiency of disclosure, i.e. a standard which would depart from the previously cited case law summarised in G 2/21 (as noted in T 979/23). Following G 2/21, a reliance on post-published evidence was not ruled out generally in the context of sufficiency of disclosure for second medical use claims. The reliance on post-published evidence could also not be limited to situations in which it served no useful purpose, i.e. cases in which the effect was already convincingly proven in the application to such an extent that the use of post-published evidence, as a superfluous confirmation of the already proven effect, would be of no relevance. The board explained that, in other words, the scope of reliance on post-published evidence was not zero.
In the case in hand, the board considered that the application as filed contained experimental data reflecting an effect on primary negative symptoms of schizophrenia, and thus disclosed the suitability of cariprazine for the claimed therapeutic indication (see T 609/02). Under these circumstances, the board established that post-published evidence D13 could be taken into account to back up the findings in the application as filed.
The board found that D13 confirmed the findings of the patent, and showed improvements in negative symptoms while excluding indirect effects related to positive, depressive, or EPS (extrapyramidal) symptoms as causal factor. Accordingly, D13 supported the conclusion that cariprazine was effective on primary negative symptoms and refuted the appellants' objection that the improvement could relate to secondary negative symptoms. Therefore, the criteria of sufficiency of disclosure were satisfied.