T 2571/12 - Plausibility strikes again (depression treatment)

Key points

• " Although depression is listed in the patent as one of the possible neuropsychiatric disorders that could be treated with glutathione precursors, there is no evidence at all, either in the patent or in the available prior art, that makes it plausible that glutathione precursors may have a therapeutic effect in depression." 
• The Board: " It is the patent that has to demonstrate the suitability of the claimed treatment for the claimed therapeutic indication. As explained, for example, in decision T609/02 supra, a simple verbal statement that compound X may be used to treat disease Y is not enough to ensure sufficiency of disclosure: rather, it is required that the patent provides some information in the form of, for example, experimental tests, to the avail that the claimed compound has a direct effect on a metabolic mechanism specifically involved in the disease, this mechanism being either known from the prior art or demonstrated in the patent per se."
• Therefore, the claimed subject-matter is insufficiently disclosed. 

EPO T 2571/12 -  link

5. Auxiliary request 1 - Article 83 EPC

5.1 In claim 1 of auxiliary request 1 the therapeutical indication has been restricted to the neuropsychiatric disorder depression.

5.2 By definition, attaining the claimed therapeutic effect is a functional technical feature of claims directed to medical uses (G 2/88, OJ EPO 1990, 93, reasons 10.3). As a consequence, under Article 83 EPC, unless this is already known to the skilled person at the priority date, the application must disclose the suitability of the product to be used for the claimed therapeutic application (see also T 609/02, reasons 9).

5.3 Although depression is listed in the patent as one of the possible neuropsychiatric disorders that could be treated with glutathione precursors, there is no evidence at all, either in the patent or in the available prior art, that makes it plausible that glutathione precursors may have a therapeutic effect in depression. In fact, there is no hint that the underlying mechanism which is extensively disclosed in the patent for schizophrenia, namely reduction of glutathione levels in the central nervous system and consequent oxidative stress, is also present in depression. Hence the board concludes that the patent does not disclose the suitability of the product to be used for the claimed therapeutic application.

5.4 The board thus disagrees with the conclusions of the opposition division that because "no evidence has been provided by O to show that any neuropsychiatric disorder cannot effectively been [sic] treated using a glutathione precursor such as N-acetyl-cysteine (...) the patent in suit is considered as disclosing the invention in a manner sufficiently clear and complete for it to be carried out by a person skilled in the art" (decision of the opposition division, page 7, second paragraph). It is the patent that has to demonstrate the suitability of the claimed treatment for the claimed therapeutic indication. As explained, for example, in decision T 609/02 supra, a simple verbal statement that compound X may be used to treat disease Y is not enough to ensure sufficiency of disclosure: rather, it is required that the patent provides some information in the form of, for example, experimental tests, to the avail that the claimed compound has a direct effect on a metabolic mechanism specifically involved in the disease, this mechanism being either known from the prior art or demonstrated in the patent per se.

5.5 Decision T 609/02 moreover clarified that post-published evidence may be taken into account for sufficiency of disclosure, but only to back up the findings in the patent application in relation to the use of the ingredient as a pharmaceutical, and not to establish sufficiency of disclosure on its own. Accordingly, post-published document D13, submitted by the appellant with the statement of grounds of appeal as evidence for a role of glutathione precursors in the context of depression, cannot be taken into account in the present context.

5.6 The subject-matter of claim 1 of auxiliary request 1 is thus not sufficiently disclosed in the application. Auxiliary request 1 is not allowable for lack of compliance with Article 83 EPC.