It is a general principle in patent law that a patent claim for a product can only be obtained if said product as such is novel. However, no law without exception. When the European Patent Convention was being drafted in Europe, “interested circles” indicated that it would be valuable to humanity to encourage research involving new therapeutic uses of known substances. As a result of said lobbying, said specific exception appeared governing novelty of a known substance or composition for a new medical use.

Said specific exception is defined in current Article 54(5) EPC with the following wording (underlining added):

Paragraphs 2 and 3 shall not exclude the patentability of any substance or composition referred to in paragraph 4 for any specific use in a method referred to in Article 53(c) EPC, provided that such use is not comprised in the state of the art.

A 2nd medical use claim having the usual structure “substance/composition X for a specific medical use covered by Article 53(c) EPC, e.g. for use in the treatment of disease Y” is therefore considered to be novel if a known substance/composition X has not been previously disclosed for the claimed specific medical use.

In the recently published decision T 558/20 of April 20, 2023, the Board of Appeal had to consider whether a granted claim having said 2nd medical use claim structure as per the following wording could be argued to be novel over the prior art, based solely on the (underlined) surgical method steps falling under Article 53(c) EPC:

A bone regenerative material comprising calcium sulphate, calcium phosphate, or demineralized bone matrix (DBM), or a combination thereof (“substance/composition X”), for use in a method of treating a patient suffering from a degenerative bone condition that can be characterized by a loss of bone mineral density (BMD)(“disease Y”), the method comprising: forming a void in a localized area of intact bone by clearing degenerated bone material and optionally removing a portion of the degenerated bone material; and at least partially filling the formed void with a bone regenerative material that facilitates formation of new, non-degenerated bone material in the void.

Since both “substance/composition X” and its use for the treatment of “disease Y” were already known from the prior art, the relevant question was therefore: Can solely said (underlined) surgical steps falling under Article 53(c) EPC establish novelty over the prior art?

In the first instance, the Opposition Division followed the opponent’s view and said “NO” to this question, essentially based on the argument that said surgery is unrelated to the claimed substance/composition and its therapeutical effect.

At the next higher instance, however, the Board of Appeal overruled the Opposition Division and took a different view as per said decision T 558/20, i.e. the Board considered said (underlined) surgical steps as novelty establishing features. The reasoning is as simple as it is convincing: Article 54(5) EPC cited above explicitly defines that “any specific use in a method referred to in Article 53(c) EPC” must be considered, which includes surgery covered by Article 53(c) EPC and being an integral part of the method defined in the claim cited above. As the Board noted with reference to the surgical steps: “This is the ‘specific use in a method’ referred to in Article 54(5) EPC, and this use needs to be compared with the disclosure of the prior art.” and “Thus, the surgical method steps cannot be ignored when assessing novelty of the claim.” The Board reversed the first instance decision and found a claim set novel according to Article 54(5) EPC based on specific surgical steps.

Lesson learned from T 558/20: For 2nd medical use claims, the EPO’s simple gold standard novelty test applies, questioning whether a skilled person can directly and unambiguously derive the claim features (here, the surgical steps falling under Article 53(c) EPC) from a piece of prior art.