What are the boundaries of a composition or substance within the meaning of Article 54(5) EPC?
Background
The Board of Appeal in decision T 1252/20 concerns an appeal to the Examining Division’s [ED] decision to refuse EP 2919826. The application relates to the use of self-assembling peptides as a solution into a blood vessel for treating various diseases. Upon contact with body fluid, these peptides aggregate to form a hydrogel, blocking the blood vessel and induce necrosis of the tissue. The primary focus of the appeal concerns second medical use claim 1, which pertains to compositions comprising solutions of the specific peptides for use in the treating of amongst others cancer.
Argumentation by the Examining Division
The ED argued that the peptide solutions defined in the claim did not qualify as a "substance or composition" within the meaning of Art 53(c), 54(4) and 54(5) EPC since their mode of action would be purely mechanical. The ED based themselves on the Guidelines for Examination G-VI 7.1.1 an T 1758/15, according to which the therapeutic effect must be attributed to the chemical properties of the product and wherein the counter-example of a filling material having only a mechanical effect is described. Following this reasoning the ED construed the claim as a device suitable for being used in the method defined in the claim, rather than a purpose-limited second medical use claim. With the use specified in the claim not being considered a limiting feature and the peptide per se being known this resulted in a lack of novelty over D1 and D2. The applicant appealed the decision submitting arguments focused on whether the peptides qualified as "substances or compositions" under the EPC.
Appeal and arguments
Contrary to the ED's stance, the Board affirmed that the peptide solutions defined in the claim do indeed qualify as "substance or composition" under Art 54(5) EPC. The key reasoning of the Board revolved around the interpretation of "substance or composition" and whether the use of peptides in a therapeutic method could be considered as such.
In appeal, the Board considered that decision G 5/83 established the patentability of second medical indications and in fact served as the basis for Art 54(5) EPC (see T 1758/15, Reasons 5.2.5). The Board also emphasized that the application of the special approach to novelty through the intended use is strictly limited to claims that are directed at substances or compositions intended for use in methods stipulated by Art 52(4) EPC 1973, corresponding to Art 53(c) EPC (G 5/83, Reasons 21, last sentence).
The question of what can be considered a ‘’substance or composition’’ in the sense of Art 54(4) and (5) EPC was further assessed in view of the established case law.
Decision T 2003/08 established the principle that in order for a product to qualify as a “substance or composition” pursuant to Art 54(4) and (5) EPC, it must be an “active agent” in the method. Furthermore, it was held necessary to establish (a) the means by which the therapeutic effect is achieved, and (b) that the therapeutic effect was achieved by a chemical entity, or a composition of chemical entities.
These criteria were further explored in T 1758/15 setting out that for a filler material exerting its therapeutic effect through its physical mass rather than its chemical properties, step (b) of the T 2003/08 test was not satisfied, i.e. the therapeutic effect was not achieved by a “chemical entity”. Rather, the filler material of T 1758/15 was considered to be acting as a “device”. Thus, purpose-limited protection for the product was denied.
The Appellant of the present case in turn highlighted that here the effect was due to the adhesion of the hydrogel, which came from the chemical structure of the peptides.
The Board then turned to the peptide of the appealed case and assessed whether a substance or composition in the sense of Art 54(4) EPC is meant.
Substance or composition
The Board firstly emphasized the distinction between:
- substances or compositions and
- medical devices
The ED's rationale, based on the Guidelines for Examination and Decision T 1758/15, suggested that if a therapeutic effect primarily results from the macroscopic 3D-structure formed by a composition inside the body, it should be considered a (mechanical) device rather than a substance or composition. The Board disagreed with this interpretation, asserting that the nature of a substance or composition should be determined based on the claimed material itself. They found that the peptide solution, defined in the claim as a liquid mixture of chemical entities, was evidently a "substance or composition" and not a device.
Rejection of Mode of Action Criterion
The Board in turn challenged the ED's reliance on the mode of action as a criterion for determining the nature of the material. They argued that statutory provisions, including Art 54(5) EPC and decision G 5/83, do not require a specific mechanism of action for a material to qualify as a substance or composition. They contended that the lack of a legal basis and practical issues, such as potential variations in the material's behavior based on administration and evolving understanding of mechanisms of action, made the mode of action an inappropriate criterium.
Conclusion and Decision
In conclusion, the Board held that Claim 1 of the main request was a second medical use claim pursuant to Art 54(5) EPC and emphasized that the substance or composition in the claim was responsible for the therapeutic effect, thereby meeting the original criteria as already outlined in T 2003/08. As a result the claims are considered novel over D1 and D2.
The case was remitted to the ED for further prosecution.
