Protecting Method of Medical Treatment Inventions: A Comparative Guide for the US, Europe, China, Japan, and Singapore

09 Oct 2024

Method of medical treatment inventions play a vital role in advancing therapeutic innovations. As a patent attorney in Singapore, I have received numerous inquiries over the years from clients in the US, Europe, Japan, and China about how to protect method of treatment inventions in Singapore. The landscape for patenting such inventions varies widely across these jurisdictions, and understanding these differences is key for biotech and pharmaceutical innovators looking to secure comprehensive protection. This article provides a comparative overview of how method of treatment inventions are treated in the United States, European Patent Office (EPO), China, Japan, and Singapore.
 
United States
In the US, method of treatment claims are patentable per se. This makes the US a unique and advantageous jurisdiction for innovators seeking protection for medical methods involving therapeutic applications. Claims can be drafted in a straightforward manner, allowing for broad protection in areas like the use of new drugs, the new use of known drugs, combinations of drugs, or new methods of drug administration.
 
For example, it is possible to claim:

• A method of treating disease Y in a patient by administering compound X.

This flexibility stands in stark contrast to most other jurisdictions, where method of treatment claims are considered non-patentable due to ethical concerns regarding medical practices. For instance, the European Patent Office (EPO), Japan, China, and Singapore do not allow method of treatment claims per se to be patented. However, the first medical use of a new substance, the first medical use of a known substance that has not been previously used for medical purposes, and the second and further medical uses of a known drug are generally patentable (provided they satisfy the usual patentability requirements), if suitable claim formats are used to protect these subject matters.
 
Europe (European Patent Office)
In Europe, a first medical use can be written in the following formats:

• Compound X for use as a medicament. (broad)

• Compound X for use in the treatment of disease Y. (EPC2000 format)

In terms of support, the broad form of a first medical use claim is allowable on the condition that there is support for at least one medical use of compound X claimed.
 
For second and further medical uses of a known drug, the EPC2000 format (also known as purpose-limited product claims) should be used:

• Compound X for use in the treatment of disease Y.

Features of a new therapeutic method, such as a new dosage regimen, administration mode, or patient group, are also patentable in Europe using the following EPC2000 format:

• Compound X for use in the treatment of disease Y, wherein compound X is [new feature].

  
China
Unlike the EPO, broad claims for the first medical use will be rejected in China due to a lack of support. The level of support required in China for broad first medical use claims is that compound X must be shown to be an effective treatment for all diseases or conditions, which is almost impossible.
As such, first, second, and further medical uses are all protected in China using the Swiss-style claim format:

• Use of compound X in the manufacture of a medicament for the treatment of disease Y.

While China does not prohibit claims related to new dosage regimens, administration modes, or patient groups, such features must be reflected as limiting features in drug manufacturing to be patentable.
 
Japan
Japan has a unique approach to claim formats for medical uses.
No specific "use" claim format is available for first medical use in Japan. Instead, the first medical use should be written as a product per se claim in the following format:

• A drug comprising compound A.

For second and further medical uses, the following two formats are preferred:

• A pharmaceutical composition for the treatment of disease Y, comprising compound X.

• A pharmaceutical composition for use in the treatment of disease Y, comprising compound X.

The Swiss-style format is also permitted to protect second and further medical uses in Japan. However, there is some uncertainty as to whether this format only provides protection for the manufacturing process itself.
 
Singapore
For first medical use, Singapore’s approach closely mirrors that of the EPO—broad first medical use claims are allowed in the following format:

• Compound X for use as a medicament.

Similar to Europe, second and further medical uses of a known drug are also patentable in Singapore, as are new dosage regimens, administration modes, or patient groups. The key difference between Singapore and the EPO is that Singapore requires Swiss-style claims for second and further medical uses.
 
Conclusion
The patentability of method of treatment inventions varies significantly depending on the jurisdiction. While the US offers broad protection for method claims, jurisdictions such as the EPO, China, Japan, and Singapore require more specific claim formats, such as purpose-limited product claims or Swiss-style claims. Innovators aiming to protect their medical inventions across multiple regions must carefully adapt their claims and even the patent specifications to align with the requirements of each patent office. Understanding these distinctions is essential for securing comprehensive protection for medical inventions in global markets. If you need further guidance on navigating these differing requirements, feel free to reach out.