Excluded Subject Matter (7) – 1st and 2nd medical uses

As covered in our previous articles on excluded subject matter, the European Patent Convention prohibits the grant of patents to "methods for treatment of the human or animal body by surgery or therapy and diagnostic methods practised on the human or animal body". However, these exclusions only apply to method claims. In contrast, claims to products, such as substances, compositions, devices, computer programs and storage media are not excluded from patentability, even if the product is intended for use in an excluded medical method. 

Nonetheless, claims to products must still meet all requirements for patentability, which includes that the product is new. Where the invention lies in a product containing new structural or chemical features, these may be protected as a new product claim. However, where the invention lies in a newly found use of an existing product, this can present significant challenges in the medical field. This is because the new use cannot be claimed directly since it would be excluded from patentability as a medical method. Meanwhile, in most cases, a claim to the product specified for the new use is only interpreted as a product "suitable for" the new use, which may not be able to provide novelty. For example, a claim to a "staple for use in abdominal surgery" would be interpreted as a staple "suitable for" use in abdominal surgery, which would not be new over an earlier staple of the same design used for any other purpose, such as stapling paper.  

1st and 2nd medical use claims

There is, however, "a special concept of novelty" in the European Patent Convention where the above general rules of novelty do not apply. This is for known substances or compositions that are specified for a new use in a medical method, i.e. a method for treatment of the human or animal body by surgery or therapy or a diagnostic method practised on the human or animal body. 

In the case where a substance or composition is already known, but was not disclosed previously for any medical use, a "1st medical use claim" may protect the substance or composition in the form "Compound X for use as a medicament". 

In the case where a substance or composition is already known and disclosed for medical use, a "2nd medical use claim" may protect the substance or composition for a further specific medical use, provided that the specific use is novel and inventive. There are various forms of 2nd medical use claim depending on the specific medical use, such as:  

• New therapies (e.g. Compound X for use in the treatment of cancer) 
• New diagnosis (e.g. Compound X for use in a method of diagnosis in vivo of cancer) 
• New surgeries (e.g. Compound X for use in a method of intracardiac catheterisation as a protector of blood vessel walls) 
• Known therapies but using a different dosage regimen (e.g. Compound X for use in treating cancer by administering a specific amount of Compound X or by a specific administration schedule) 
• Known therapies but for a different patient group that is distinguished from a former group by its physiological or pathological status (e.g. Compound X for use in the treatment of cancer in a patient who experiences an inadequate response to a specific inhibitor) 
• Known therapies but using a different mode or route of administration (e.g. Compound X for use in the treatment of cancer by intramuscular administration) 

In all of the above cases, the new medical use is carried out in a new way that can be distinguished from previous medical uses. In contrast, 2nd medical use claims are not available where a known therapy is carried out in a known way, with only a newly identified mechanism of action, since this is considered a mere discovery and not technical. 

Meaning of "substance or composition"

"Substances and compositions" are not defined in the European Patent Convention, but are discussed in case law as "a chemical entity or composition of chemical entities" that is responsible for the medical use.  

For example, paracetamol is a chemical entity that is responsible for treating pain. It is therefore considered a "substance" eligible for protection with a 1st or 2nd medical use claim.  

A stent is a medical device that is responsible for a medical effect. However, a device is not a chemical entity and is therefore not considered a "substance or composition" eligible for protection with a 1st or 2nd medical use claim. 

Polyethylene is a chemical entity and may be used to form a stent. However, polyethylene is not in itself responsible for the medical effect provided by the stent. Polyethylene is therefore not considered a "substance or composition" eligible for protection with a 1st or 2nd medical use claim. 

A collagen and hyaluronic acid filler material for use as an injectable spacer in radiation treatment, which achieves the effect of reducing radiation-treatment-induced side effects by mechanically displacing sensitive tissue relative to target tissue, has also been found by case law to not be a "substance or composition". This was because the mechanical displacement of tissue was achieved by the three-dimensional accumulated mass of filler material, not as a property of the filler material as a chemical entity or composition of chemical entities. The therapeutic effect of the filler material, such as holding open a particular volume and distancing sensitive tissue, was considered to be an effect of the 3D macroscopic structure of the filler, which was only indirectly attributable to the chemical entity. 

In contrast, a dye used for selectively staining the outer surface of the eye lens in cataract surgery may be considered a "substance or composition" eligible for protection with a 1st or 2nd medical use claim. This is because the dye is a chemical entity and the means by which the selective staining facilitating the surgery is achieved. 

Thus, in the pharmaceutical field, it is usually straight-forward to identify where a chemical compound is eligible for protection as a substance or composition with a 1st or 2nd medical use claim.  

In contrast, it can be extremely difficult to rely on a 1st or 2nd medical use claims outside the pharmaceutical field, where the identification of substances or compositions is subtle and relies on detailed technical analysis.  

Conclusion

1st and 2nd medical use claims are an extremely useful form of protection at the European Patent Office, but only for certain products. Known substances and compositions may be protected for a variety of new medical uses. However, other medical products, such as medical devices, can fall into a difficult gap lacking protection, since the method of use is likely to be excluded from patentability as a medical method, and 1st or 2nd medical use claims not available. For this reason, protecting medical devices in Europe can present particular challenges. 

This article is a part of our EPO Practice and Peculiarities series. Click here to explore.