“In theory, product claims provide the strongest patent protection because they are not limited to the use or preparation of the Traditional Chinese Medicine (TCM) product. In reality, however, infringement assessment often involves looking at the methods used to prepare the TCM product.”
Traditional Chinese Medicine, or TCM, is a subset of herbal medicine. TCM patent applications generally fall into four categories.
- A Compound formula is the predominant type of patent application in the field of Chinese medicine. This is not surprising because most TCM combines two or more medicinal materials to be effective.
- Medicinal craft refers to active ingredients extracted from medicinal materials using a specialized process, or the specialized process itself.
- Medicinal materials refer to the original medicinal materials used in the preparation of Chinese medicines. Some of these original medicinal materials are the whole plant or a certain part of the plant, and some need to be processed.
- Related products refer to non-medicinal products containing Chinese medicines, including medicated foods, namely functional foods, health products and cosmetics containing Chinese medicines.
These categories reflect the main objectives of TCM patent protection: namely, to protect the formula, craft, original materials, and commercial products.
Claim Forms and Scope
Method claims are useful when the TCM product’s preparation, purification, or extraction process is innovative, but the final composition is unclear. It’s important to define the claim form based on the characteristics of raw materials, the process, and dosage. Raw materials should include all components and proportions used to prepare the TCM product. The process should include all steps and conditions, such as temperature, pressure, time, etc. The dosage can be broadly described as “medicament,” if a person skilled in the art could understand what that means in light of the patent; otherwise, the dosage needs to be specific. Below is an example of a TCM method claim:
A method for producing a medicine for postpartum treatment, prepared from: 20-30 parts by weight of motherwort, 3-9 parts by weight of angelica, 1-6 parts by weight of ginseng, 6-12 parts by weight of astragalus, and 5-13 parts by weight of Polygonum multiflorum, Peach kernels 4-7 parts by weight, Cyperus rotundus 6-9 parts by weight, mixed with water and decocted twice, the amount of water added each time is 10 times the amount of raw materials, and the decoction is 1-3 hours each time. The decoction is combined, filtered, and the filtrate is concentrated into a clear paste with a relative density of 1.25 to 1.28, 40 to 70 parts by weight of brown sugar and 5 to 10 parts by weight of dextrin are added to make granules, which are dried into granules.
A method claim’s scope extends to the product obtained by the method. Article 11 of China’s Patent Law provides that “after the invention patent right is granted, unless otherwise provided in this law, no entity or individual may exploit the invention without the permission of the patentee, that is, not use, promise to sell, sell, or import products directly obtained in accordance with the patented method.”
Use claims are useful when the TCM product’s application is innovative. The “Examination Guidelines” provides this basic formula: “The application of substance X in the preparation of therapeutic drug Y.” Further, if effective ingredients are known, the claim can be written as “[t]he application of substance X in the preparation of therapeutic drug Y, where the effective ingredients are Z.”
A use claim’s scope, however, is limited to the claimed use. Therefore, obtaining a corresponding method claim is advantageous when applicable to protect the preparation, packaging, and promotion of the TCM products.
Lastly, product claims are useful when the TCM’s final composition is known. In theory, they provide the strongest patent protection because they are not limited to the use or preparation of the TCM product. In reality, however, infringement assessment often involves looking at the methods used to prepare the TCM product. The bottom line is that there needs to be sufficient evidence that a product prepared by a different method is the same product prepared by the inventor.
Special Features of TCM Patents in Chinese Patent Infringement Lawsuits
As discussed before, method claims are useful when the TCM product’s preparation, purification, or extraction process is innovative, but the final composition is unclear. Most TCM patents fall under this category and these patents present some unique challenges in litigation.
For example, Beijing Yadong Biopharmaceutical Co., Ltd. (“Yadong”) and Guizhou Kangna Shengfang Pharmaceutical Co., Ltd. (“Kangna”) were involved in a TCM patent dispute in the Beijing No. 1 Intermediate People’s Court. [(2006)??????8603?.] The Court found that claim 3 of Patent No. ZL02134148.6 was different from Yadong’s TCM capsules. Specifically, the Court found that in claim 3, “Fructus corni is decocted three times with water…drug residue plus 5 times the amount of 90% ethanol for reflux extraction twice, 1 hour each time,” where Yadong’s capsule was “Fruit Cornus plus ethanol refluxed for a second time…drug residue for use,” which constituted a significant difference. Therefore, the prescription and preparation method of Yadong’s capsules did not fall within the protection scope of claim 3.
Another example includes the appeal of a patent infringement dispute between Guizhou Baixiang Pharmaceutical Co., Ltd. (“Baixiang”) and the patent owner Zhao Shusheng. [(2011)???????6?.] Baixiang, the defendant, obtained drug registration approval and disclosed its preparation method in the drug label. The most significant difference is that the asserted patent recites using two ethanol reflux and the defendant adopted the technique of three ethanol refluxes, and the time of each reflux was also different.
The plaintiff argued that three-reflux and two-reflux are technologically equivalent. The Court disagreed for two reasons. First, although three-reflux and two-reflux both extract the active ingredients from yantuo, the plaintiff did not provide sufficient evidence that they achieve the same extraction results. Second, the defendant showed that three-reflux had far better extraction results than two-reflux. Plaintiff’s witnesses also admitted that increasing the number of refluxes was more efficient.
These are typical examples of TCM patent disputes where the active ingredients are mostly characterized by extraction and preparation methods, making it difficult to enforce patent rights.
TCM, as a subset of herbal medicine, has similar patent protection principals and challenges in the United States. Composition claims are useful when the active ingredients are known and can be limited to a specific use. For example, Frisun, Inc. (Wuhan, China) obtained U.S. Patent No. 7,575,772 on “Process and composition for syrup and jam from Luo Han Guo fruit” that “brings all the advantages of Luo Han Guo together to meet today’s market demand for a natural, sugar-free sweetener.” In TCM research, Luo Han Guo (or Monk fruits) is known to have the potential to be natural sweetener with a low glycemic index and can therefore be an alternative to sugar for diabetic populations. See, e.g., Ying. Z., Yan. Z., Jeff. E., Chi-Fu. H., Insulin secretion stimulating effects of mogroside V and fruit extract of Luo Han Kuo (Siraitia grosvenori Swingle) fruit extract., Acta Pharmaceutica Sinica., 44 (11): 1252-1257 (2009).
The number of patent acquisitions for herbal medicines has grown significantly. From 1976 to 2003, the U.S. Patent and Trademark Office (USPTO) granted a total of 1,968 herbal patents. [Surge in US patents on botanicals, NATURE BIOTECHNOLOGY VOLUME 22 NUMBER 6 JUNE 2004.] Since 2019, the USPTO has received more than 4,000 herbal patent applications since 2019. This number is fairly conservative, because many new application forms have not yet been made public. Below are a few:
The Challenge Will Increase
Patent protection for TCM can present many challenges because of the various types of TCM products and the uncertainty of the active ingredients. As herbal medicine patents become more popular, we can expect to see similar challenges in enforcing patent rights in herbal medicine technology.