CABINET CHAILLOT

T 0728/21 - Sufficiency of disclosure

Sufficiency of disclosure, G 2/21, Art 83 EPC

T 0728/21
The opponent filed appeals against the interlocutory decision of the opposition division that the patent as amended in accordance with auxiliary request 16 met the requirements of the EPC.
Claim 1 of the mentioned auxiliary request 16 relates to a pharmaceutical composition in the form of a tablet comprising a solid dispersion and other components; wherein the solid dispersion comprises 80 wt% of ivacaftor by weight of the dispersion, for use in treating or lessening the severity of cystic fibrosis in a patient; wherein the patient possesses a cystic fibrosis transmembrane receptor (CFTR) with a DeltaF508 mutation on both alleles.
The difference between the subject-matter of the main request and the closest prior art D2 concerns the definition of the particular constitution of the claimed tablet.
The respondent presented in its reply to the appeal results from experiments concerning the combined effect of the weight ratio of the different components on the dissolution properties of the prepared tablets.
In view of the results, the Boards considers that an optimization of the dissolution is achieved in claim 1 of the main request.
According to G 2/21 a technical effect may be relied upon for inventive step if the skilled person, having the common general knowledge in mind, and based on the application as originally filed, would derive said effect as being encompassed by the technical teaching and embodied by the same originally disclosed invention. The application as originally filed explicitly addressed the dissolution of tablets comprising a solid dispersion as an aspect of the disclosed invention and specifically described the claimed tablet composition as an embodiment of the disclosed invention. The effect of the optimization of the dissolution associated with the specific tablet composition defined in claim 1 of the main request may therefore, in accordance with the principles established in G 2/21, be taken into account for the assessment of inventive step.
Accordingly, the objective technical problem may be seen in the provision of a tablet formulation comprising a solid dispersion of amorphous ivacaftor which exhibits optimized dissolution.
No prior art document provides any suggestion that the combination of the components of the composition as claimed would allow the preparation of a tablet which exhibits optimized dissolution.
The subject-matter of claim 1 was therefore not obvious as solution to the objective technical problem. The Board concludes that the main request meets the requirement of inventive step.
In case a patent defines a new therapeutical utility of a composition in a claim in the format of Article 54(5) EPC, it is according to the established jurisprudence necessary for compliance with Article 83 EPC, in order to ensure that a patent is only granted if there is a corresponding contribution to the prior art, that the patent at the date of its filing renders it credible that the claimed composition is indeed suitable for the defined therapeutic use (G 2/21). A deficient disclosure cannot be remedied by post-published evidence (see G 2/21; compare G 1/03).
The patent does thereby not describe the activity of ivacaftor as a CFTR potentiator in the form of a simple verbal statement, which might be considered not to be sufficient, but rather as specific and verifiable technical information supporting the defined therapeutic indication.
This information in the patent provides according to the Board a rational basis for the claimed invention, which rendered the utility of the claimed composition in the treatment of homozygous DeltaF508 patients credible at the date of its filing.
In accordance with the jurisprudence exemplified by T609/02, the suitability of the claimed composition for the defined use needs to be disclosed in the patent, "unless this is already known". This jurisprudence confirms in the Boards view that the disclosed utility of the claimed composition may also derive its credibility from the prior art, even if this prior art does not represent common general knowledge.
Document D16A describes ivacaftor as an orally bioavailable potentiator of CFTR with activity in cultures of DeltaF508/DeltaF508 human bronchial epithelia. The information that ivacaftor is a CFTR potentiator of DeltaF508 CFTR was therefore as a matter of fact already part of the prior art. The Board therefore considers that the prior art confirms the credibility of the disclosed utility of the claimed composition.
In as far as a patent provides a credible disclosure of the claimed invention a convincing objection of lack of sufficiency of disclosure presupposes according to the established jurisprudence that serious doubts substantiated by verifiable facts have been raised that the skilled person cannot carry out the claimed invention without undue burden on the basis of the teaching in the patent and the common general knowledge.
The appellant argued that the post-published document D15 raises serious doubts regarding the utility of ivacaftor in the treatment of homozygous DeltaF508 patients as defined in claim 1 of the main request, because this document reported a lack of clinical benefit from treatment of homozygous DeltaF508 patients with ivacaftor alone.
However, as pointed out by the respondent, document D15 actually reported that measurable effects from administration of ivacaftor in homozygous DeltaF508 patients had been observed, be it that these effects could not be qualified as a statistically significant clinical benefit. In the Board's view this "lack" of observation does not qualify as verifiable evidence that raises serious doubts regarding the credibly disclosed suitability of the claimed composition comprising ivacaftor for the defined combination treatment of homozygous DeltaF508 patients.
Accordingly, the Board concludes that the main request meets the requirement of sufficiency of disclosure.
The appeal is dismissed.

 

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