Overview of Pharmaceutical Patents in China

Written by Mr. Jian Xu, IP Expert and collaborator of the China IP SME Helpdesk

 

With China's market size as well as population, pharmaceutical companies, foreign or domestic, are developing their business rapidly in China. However, the Chinese landscape is difficult to navigate and poses a number of problems; none more so than patent issues. This article is a primer on the various categories of pharmaceutical patents in China.

Patents on Pharmaceutical Products

Natural substances

A substance, found in the nature and existing in its natural state, is merely an object of discovery in the sense of the "scientific discoveries" and thus not patentable. However, if a substance is isolated or extracted from the nature for the first time, of which the structure, the morphology or other physical/chemical parameters are unknown in the prior art and can be precisely characterized, the substance can be patentable in China.

Chemical/Pharmaceutical Compounds

Patents for chemical/pharmaceutical compounds are usually most desirable form of patents for pharmaceutical companies, as it offers the broadest coverage and strongest enforcement for the patent technology. To apply for the invention of a compound, the patent shall indicate the chemical name and the structural formula (including various function groups, molecule steric-configuration and so on) or the molecular formula of said compound. The explanation of the chemical structure must be clear and detailed enough to avoid objections of insufficient disclosure. In order to clearly identify the claimed compound, the patent should also describe the chemical/physical property parameters (such as the various qualitative or quantitative data and spectrum, etc.) relating to the compound.

If a compound has been mentioned in the prior art in sufficient detail, then the compound is presumed to lack novelty. For example, if the name and the molecular formula of a compound disclosed in the prior art are unclear, but the prior art discloses the same physical/chemical parameter, or the same method of preparation, then the compound is usually presumed to lack novelty.

Pharmaceutical Compositions

Many pharmaceutical products exist in composition form so it is another popular category of patents for pharmaceutical companies. The patent for a composition should describe both the components and the contents thereof. There are two modes of claim of a composition: open-ended and close-ended. The open-ended mode means that the composition does not exclude those components that are not mentioned in the claim. The close-ended mode means that any of the other components that are not mentioned in the claim shall be excluded. Wording such as "comprising", "including", and "containing" usually indicates an open-ended claim, while wording such as "consisting of...", "be composed of..." and "be balanced with ..." shows a close-ended claim. Obviously, where possible, open-ended claims are more desirable as they have broader coverage.

Microorganisms

The term "microorganism" includes bacteria, actinomycetes, fungi, viruses, protozoa and algae, etc. A microorganism existing in the nature without the involvement of any artificially induced technical treatment is, however, a scientific discovery and thus unpatentable. Microorganism per se is eligible for patent protection when it is isolated into pure culture and has particular industrial use.

Genetic engineering products

Inventions of genetic engineering is usually related to a gene, a vector, a recombinant vector, a transformant, a polypeptide or a protein, a fused cell, a monoclonal antibody, etc. To clearly define the product, the patent shall indicate the structure of the product, such as base sequence of a gene, amino acid sequence of a polypeptide or protein, etc. When the structure of the product cannot be clearly described, the patent shall describe the physical/chemical parameters, biological property and/or preparation method of the product, etc.

There are a few notable novelty considerations relating to genetic engineering.

For genes, if a protein per se possesses novelty, the invention of the gene encoding the protein also possesses novelty.

For recombinant protein, if a protein as an isolated and purified single substance is known, an invention concerning a recombinant protein defined by a different preparation process and having an identical amino acid sequence does not possess novelty.

For monoclonal antibody, if antigen A is novel, a monoclonal antibody of antigen A is considered novel. However, if a monoclonal antibody of a known antigen A' is known and that the antigen A involved in the invention has the same epitope as that of antigen A', it is deduced that the monoclonal antibody of the known antigen A' is capable of binding to antigen A. In such a case, the invention of the monoclonal antibody of antigen A usually does not possess novelty.

Components of Plants and Animals

China does not grant patent rights to plants or animals, including transgenic animals or plants. However, animal somatic cells, tissues and organs meeting novelty requirements are eligible for patent protection. Plant cells, tissues and organs are also eligible for patent protection provided that they don't independently constitute a certain variety of plants.

Patents on Pharmaceutical Methods and Processes

Apart from pharmaceutical products per se, there are significant amount of inventions in the pharmaceutical sector which relates to various methods or processes, such as process for preparing substances, method of application, process method or treatment method of substances. They are defined by the features of the process relating to procedure, substance and apparatus.

The process features relating to procedure include process steps (it may also be reaction steps) and process conditions, such as temperature, pressure, time, catalysts or other auxiliaries used in process steps.

The process features relating to substance include the chemical component, chemical-structural formula, physical/chemical property parameters of the raw material used in the process and the product.

The process features relating to apparatus include the type of the apparatus specially adapted in said process and the property or function of the apparatus relating to said process invention.

Please note that, in practice, it is quite difficult to enforce a patent based on methods/processes, because the methods are usually internal production procedures and therefore difficult to find out, especially in China where there is basically no discovery or disclosure procedure during trials. The right holder may frequently rely on the court to carry out an evidence preseveration order to collecting and preserving evidence on the production site of the accused party.

Patents on the Use of Pharmaceutical Products

As it is not easy to invent totally new chemical compounds for pharmaceutical purpose, a lot of pharmaceutical products are developed by discovering a medical use or even second medical use of a known chemical compound. It is also possible to obtain patents directed to the pharmaceutical use of existing chemical compounds. The invention relating to the use of a chemical product is made on the basis of discovery of a new property of the product and the use of such property. Regardless of a new or known product, its property is inherent in the product per se. The essence of the use invention does not lie in the product per se, but in the application of its property.

Regarding medical use, it is important to note that China does not grant patents for “method for the diagnosis or for the treatment of diseases”. Therefore, an application relating to the medical use of a substance shall not be granted if its claim is drafted in the wording "use of substance X for the treatment of diseases", "use of substance X for diagnosis of diseases" or "use of substance X as a medicament". However, since pharmaceutical products and a method for the manufacture thereof are patentable, the application for the medical use of a substance is usually drafted in the form of method for preparing a pharmaceutical, such as "use of substance X for the manufacturing of a medicament", "use of substance X for the manufacturing of a medicament for the treatment of a disease" and so on.

A known product is not rendered novel merely because a new application has been put forward. For example, if product X is known as a detergent, then the product X used as a plasticizer does not possess novelty. However, a known product does not destroy the novelty of its new use if the new use per se is an invention. This is because such use invention is an invention of method of application, and the substance of the invention lies in how to apply the product rather than the product per se. For example, said product X is originally used as a detergent. Then, someone discovers from research that it can be used as a plasticizer after adding certain additives. Then its preparation, the kind of additives selected and the proportion etc., are the technical features of the method of application. Such new use is therefore potentially patentable.

As for a medical-use invention relating to a chemical product, the following aspects are usually taken into consideration when the examination of novelty is carried out.

(1) Whether or not the new use is different in substance from the known use. The use invention does not possess novelty when the difference between the new use and the known use lies merely in the form of expression, but the substance of them is the same.

(2) Whether or not the new use is revealed directly by the mechanism of action or pharmacological action of the known use. The use does not possess novelty if it is directly equivalent to the mechanism of action or pharmacological action of the known use.

(3) Whether or not the new use belongs to generic (upper level) term of the known use. The known use defined by specific (lower level) term may destroy the novelty of the use defined by generic (upper level) term.

(4) Whether or not the features relating to use, such as the object, mode, route, usage amount, interval of administration can define the procedure of manufacture of a pharmaceutical. The distinguishing features merely present in the course of administration do not enable the use to possess novelty.

 

This article was originally published on Dr Jian Xu's Linkedin profile.

Dr Jian Xu is the managing director of Gowling WLG’s Beijing office, and heads up the firm’s Chinese intellectual property practice. He is a dual qualified Chinese lawyer and patent and trademark attorney practising since 2006. He is the author of the book “Chinese Intellectual Property – A Practitioner’s Guide“, published by China IP Publishing House in 2013.