Surgery, therapy, and diagnostics through the lens of the European Patent Convention

The European Patent Convention (EPC) excludes patenting treatment methods by surgery or therapy and diagnostic methods. Substances or compositions for use in these methods can, however, still be patented. How this stipulation translates into practice depends on the meaning of the terms “methods of treatment by surgery”, “methods of treatment by therapy”, and “diagnostic methods”. Read on as we dive into a selection of recent decisions that shed light on the borderline possibilities for patenting surgical, therapeutic, and diagnostic inventions.

Surgery

Decision G 1/07 clarifies that a “method of treatment by surgery” is a method that involves at least one invasive step, and nuances a “narrower understanding”.

“[method of treatment by surgery] comprises or encompasses an invasive step representing a substantial physical intervention on the body which requires professional medical expertise to be carried out and which entails a substantial health risk “

“[does not apply to] techniques […] generally carried out in a non-medical, commercial environment like in cosmetic salons […] such as tattooing, piercing, hair removal by optical radiation, microabrasion of the skin […]” (G 1/07)

Subsequent decisions T 1695/07 and T 0141/15 highlight that, despite “narrower understanding”, the term “surgery” may still be broader than its normal (medical) meaning. For example, normally speaking, kidney dialysis relates to the field of nephrology, a non-surgical discipline. However, as outlined in T 1695/07, kidney dialysis involves a large amount of blood flowing at a high rate outside of the human body. In this context, the blood is not an uncritical body part; and the physical intervention constitutes a surgical method since it is not a “minor” intervention, and carries a substantial health risk, requiring professional medical expertise. T 0141/15 further specifies that determining a parameter, which is inextricably linked to kidney dialysis, likewise concerns a surgical method.

On the other hand, the recent decision T 0558/20 shows that even a, seemingly minor, modification of a known surgical method may provide novelty and inventive steps when claiming a composition for a specific use in that surgical method. The application was related to the removal of bone material, and then filling the created void with bone regenerative material. By claiming the bone regenerative material for use in the (surgical) method, rather than the method itself, the applicant sidestepped the patentability exclusion.

In this case, the bone regenerative material was considered patentable, even though the novelty and inventiveness hinged only on differences in the surgical steps: the creation of a channel in the bone and the formation of a larger void inside the bone through that channel, instead of formation of a void in the bone (already disclosed in the prior art).

Therapy

In its Board of Appeal (BoA) decisions of 2024, the EPO mainly continues to emphasize that the concept of “therapy” under Article 53(c) EPC must not be diluted.

In T 0815/12, the Board ruled that providing nutrition, such as infant formula promoting normal growth, does not qualify as therapy under Article 53(c) EPC, as it does not treat a pathological condition. Similarly, in T 1259/22, the patent related to the administration of plerixafor to a donor to mobilize pluripotent stem cells, the harvesting of the cells, and the subsequent therapeutic administration to a patient. The Board considered that plerixafor neither provided a therapeutic benefit to the healthy stem-cell donor nor impacted therapy/surgery during the harvesting phase. During patient treatment, the therapeutic effects were derived from the harvested stem cells and not plerixafor.

The Board clarified that multi-step methods involving therapeutic steps must establish a clear treatment-related link between the claimed substance and at least one step of said method. Without this link, the method cannot be classified as therapeutic and, therefore, falls outside the exceptions under Article 54(5) EPC, constituting unpatentable subject matter under Article 53(c) EPC.

In stark contrast, T 1252/20 suggests a broadening of the concept of “therapy” by expanding the interpretation of “substance or composition” under Articles 54(4) and 54(5) EPC. While earlier cases like G 5/83 and T 1758/15 emphasized that therapeutic effects must arise from chemical properties, T 1252/20 rejects this requirement.

“As generally understood, the concept of “therapy” includes treatment with chemical substances or compositions.” (G 5/83)

The Board of T 1252/20 stated that neither the EPC nor G 5/83 limits “substance or composition” to chemical modes of action. Specifically, materials or objects could qualify as “substances or compositions” regardless of how they act on the human or animal body, provided they serve a medical purpose. It held that the peptide solution that turned into a blood vessel blocking hydrogel after administration was a patentable composition for use in treatment, even though the therapy is based on a physical rather than a chemical mechanism of action. This broader interpretation may expand the scope of what can be considered patentable therapeutics under the EPC framework.

Diagnosis

G 1/04 defines what constitutes a “diagnostic method” per Art 53(c) EPC, and is enshrined in the practice at the EPO.

“[in order to fall under the prohibition,] the claim is to include the features relating to:

(i) the diagnosis for curative purposes stricto sensu representing the deductive medical or veterinary decision phase as a purely intellectual exercise, …

… the method steps of a technical nature … must satisfy the criterion “practiced on the human or animal body”

In the earlier decision T 143/04, relating to a method of diagnosing Alzheimer’s disease based on the image of a patient’s pupil, the applicant had argued that the method was not practiced on the human body because the presence of a human body is not necessary for the data processing step. However, the Board noted that the data processing step is not part of the examination phase which determines the diagnostic character of a claimed method. It was therefore inconsequential for Art 53(c) EPC whether the data processing step met the condition of being practiced on a human or animal body. 

In the more recent T 1920/21 decision, relating to a breath test for diagnosing a Helicobacter pylori infection, the Board considered that not all steps of technical nature were “practiced on the human or animal body”. It held the view that, even though the breath samples were collected directly from the patients, it is common knowledge in the field that the subsequent analysis of the breath samples can be performed using non-invasive devices, without any interaction with the patient or necessitating the presence of the patient.

The situation of T 1920/21 may seem to be similar to T 143/04, albeit each reached a different outcome. The Boards appear to have taken into account the nuanced difference between measuring a parameter directly on (or in) a patient, versus collecting a sample from a patient which is then processed remotely to measure a parameter. It is the step of measuring a parameter which is considered an integral step of a method of diagnosis per G 1/04, and which should not involve the presence of a human or animal body for the diagnostic method to be patentable.

Future outlook

An in-depth understanding of the intricacies of European case law is indispensable to determine which medical inventions may be patentable under the EPC framework, and to also choose the most appropriate claim language to avoid falling under any exclusions from patentability.

The categories “surgery”, “therapy”, and “diagnosis”, though all relating to medical methods, each require their specific approach. For instance, a method falls under surgery or therapy if only a single step qualifies as such. Whereas for a diagnostic method, all the steps constitutive for making a diagnosis must be practiced in/on a human/animal body for it to be excluded from patentability.

When it comes to “surgery”, since the interpretation of this term under patent law may differ from its normal medical meaning, a detailed assessment of all aspects of the “surgical” method is required to determine if e.g. both the method itself as well as any compositions being used therein also fall under the exclusion or not. The 2024 decisions further highlight the ongoing tension between maintaining a clear and precise definition of “therapy” under the EPC and accommodating evolving interpretations of “substance or composition”.

On the same stead, if the recent decisions are any indication, there may be an opportunity for new innovative diagnostic means, which aim to simplify sample collection and processing to minimize the interaction between humans and animals, to not fall under the exclusion.

Future challenges will likely center on balancing the need for consistency in case law with the flexibility required to address advancements in medical technologies and their patentability.