T 0243/22 - Counting to one for inventive step

Key points

• It was common ground between the parties that document D1 [US 2006/0074073] was the closest prior art. D1 (paragraphs [0002], [0003] and [0006]) is directed to rucaparib or rucaparib salts for use as chemosensitisers: [] Paragraph [0043] of D1 discloses a list of about 60 pharmaceutically acceptable salts that can be used for the invention [including maleate].
• Paragraph 0043 is just a list under the "phrase “pharmaceutically acceptable salt(s)”, as used herein"
• D1 is only about rucaparib. Hence, there is not  a two-fold selection of a salt and a compound from a class of compounds. 
• Claim 1 is a second medical use claim specifying the maleate form. 
•  The board agrees with the appellant that the starting point should be the whole list rather than the specific option of the maleate salt. As explained by the board in decision T 1126/19 (Reasons 6.2.2), which deals with the patent deriving from the earlier application, the disclosure of the closest prior art must be considered on the basis of its technical information without the latter being distorted or misrepresented by the knowledge of the invention (see also T 970/00, Reasons 4.1.2)."
• "n paragraph [0043] of D1, the maleate salt of rucaparib is not singled out. D1 neither illustrates nor presents rucaparib maleate as a standalone embodiment. Paragraph [0043] is merely a notional disclosure, in which maleate is one option in a long list of possible options, but is not among the preferred options. "
•  Starting from the list of pharmaceutically acceptable salts in paragraph [0043] of D1, it was undisputed that the subject-matter of claim 1 differs in the selection of maleate as the rucaparib salt and the requirement for the salt to be in crystalline form."
• " the board agrees with the appellant [proprietor] that the objective technical problem is the provision of a rucaparib form which has a suitable combination of properties for development into a solid dosage form."
• "D1 does not deal with the formulation of rucaparib. It contains no teaching on the issue of whether any of the salts in the long list in paragraph [0043] might possibly be suitable for preparing a solid dosage form. As the board acknowledged in decision T 1126/19 (Reasons 6.7), it is common general knowledge that finding a salt of an active compound which has a balanced combination of properties making it suitable for a solid formulation is generally a difficult, semi-empirical task, which requires non-routine experimentation and has an uncertain outcome. Thus, the skilled person would need to study each of the salts in paragraph [0043] of D1 to assess: first, whether it is solid; second, how many solid forms it may adopt; and third, whether there are forms with properties suitable for a solid formulation."
• After some analysis:  "Therefore, the board concludes that the subject-matter of claim 1 involves an inventive step."' 

EPO 

The link to the decision can be found after the jump.

https://www.epo.org/en/boards-of-appeal/decisions/t220243eu1