Japan’s patent issues relating to life science therapeutic inventions

Abstract

Japan has made ‘innovation in science and technology’ as one of its central pillars to ensure high growth in its next stage of economic development and its life sciences market which hosts regenerative medicine was proclaimed to be ‘the best market in the world right now.’ Although life science therapeutic inventions are patentable subject matter under Japanese patent law, there are nuanced obviousness and enablement challenges under Japanese patent law that can be surmounted in view of some encouraging Japanese court developments in fostering a pro-patent applicant environment in the life sciences therapeutic patent field. Nevertheless, great care must be taken when drafting and prosecuting such patent applications in the world’s second most important life sciences therapeutic market.

Keywords::

• Intellectual Property High Court
• Japan
• patent
• therapeutic

1. Introduction

Following a 2012 Nobel Prize for induced pluripotent stem cells, Japan has made ‘innovation in science and technology’ one of the central pillars in policies designed to ensure high growth in its next stage of its economic development [1]. Japan’s life sciences market is considered ‘the best market in the world right now’ [2]. It has high growth rates in pharmaceutical sales and policies designed to maintain this growth. This enthusiasm for life sciences segues with the investing world’s renewed interest in life sciences companies resulting in more money raised in the American stockmarkets in 2013 ‘than at any time since the golden year of 2000’ [3]. Under Prime Minister Shinzo Abe’s revitalization economic strategy, the government aims to expand the life sciences market (pharmaceuticals, medical devices and regenerative medicine) by ∼ 30% – from $120 billion to $160 billion – by 2020 [4].

These developments together with Japan’s current position as the world’s second largest national pharmaceutical life sciences market [5] make it critical for pharmaceutical companies, both innovator and generic, to seriously understand Japanese patent law relating to biomedical life science inventions. Historically, Japanese pharmaceutical companies have maintained a solid track record of success [6] in pharmaceutical research and development. This proud tradition was reaffirmed in 2013, when Japan had the second largest number of global first-in-class pharmaceutical launches in the world after the US [7].

This article provides an up-to-date overview of the increasingly improved environment for patents on life science therapeutic inventions in Japan. In addition, it highlights developments in the Japanese court system seen as fostering a pro-patent applicant environment in the life sciences therapeutic patent field.

2. Industrially applicable inventions: medical method not statutory matter

All patents must be industrially applicable under Japan’s Patent Law [8]. With regard to life sciences medicinal inventions, industrial applicability is very clear: anything that can be manufactured and sold is patentable subject matter in Japan, and thus compounds, compositions and methods of making these products are patentable. However, medical activities normally practiced by a medical doctor such as methods for treatment of the human body by surgery or therapy and diagnostic methods practiced on the human body are not industrially applicable and hence not statutory subject matter. However, compositions, devices, systems or kits for use in the medical surgery and treatment or diagnosis to be practiced on the human body are industrially applicable and patentable subject matter.

3. Pharmaceutical compositions

First and second pharmaceutical uses are patentable in Japan, and although a novel product or composition is patentable per se, a pharmaceutical composition is generally required to be limited to a specific use or uses under Japanese practice. Thus, open-ended claims such as ‘a composition comprising X for use as a pharmaceutical’ are usually not patentable, even if the application at hand provides the first disclosure of pharmaceutical effects.

Thus, regardless of whether it is a first or second medical use, under Japanese practice, pharmaceutical compositions are generally protected by claims of the format similar to European Patent Convention-2000: for example, ‘a composition comprising X for treatment of Y’. Claims of this sort are considered as regular product claims. Unlike in the US where the use limitation carries patentable weight and is read into the claim. Swiss-type claims, for example, ‘the use of X for the manufacture of a medicament for the treatment of Y’, are also patentable under Japanese practice, although composition claims offer a broader scope of coverage relative to Swiss-type claims under current Japanese practice.

4. Enablement and written description

The enablement/written description requirement with regard to pharmaceutical compositions under Japanese patent law is rigorously strict, in that pharmacological data or its equivalent must be present in the specification as filed. The leading decision by the Japanese IP High Court [9] confirmed this hardline rule; if the specification as originally filed fails to specifically describe actual pharmacological data relating to a claimed pharmaceutical composition, then such a pharmaceutical composition is not recognized to be enabled and postfiling data showing such activity is not permissible.

In addition, the Japanese Patent Office (JPO) generally requires mass spectroscopic data or similar physical/chemical property data to be present in the specification for chemical compounds to confirm that said compounds have been made.

Another enablement issue arises if the claims can be considered to encompass nonfunctional compounds within the composition, that is, those that cannot be recognized to have utility or attain the effects of the claimed invention. Then, the claimed invention will not be considered to fulfill the requirements of enablement (and likely written description). If only a small number of compounds are tested in pharmaceutical composition form, the JPO regularly assumes that nonfunctional compounds are encompassed by the claims.

This position has been upheld at the Tokyo High Court where it was conclusively determined that either usefulness in regard to all peptides included in the scope of the claims should be described in the specification or such usefulness should be clear to a person skilled in the art from common general technical knowledge [10].

Life science inventions that do not have supporting pharmacological data in the specification as filed will routinely be rejected by the JPO on the basis that they do not satisfy the written description and/or enablement requirements.

With regard to the determination of the presentation of pharmacological data or the equivalent in the specification, the JPO Examination Guidelines [11] put forth the following:

Since the result of the pharmacological test is to confirm the pharmacological effect of compounds etc. of the claimed medicinal invention, all of the followings should be made sufficiently clear, in principle: (i) which compounds etc. are (ii) applied to what sort of the pharmacological test system, (iii) what sort of result is obtained, and (iv) what sort of relationship the pharmacological test system has with the medicinal use of the claimed medicinal invention. It should be noted that the result of the pharmacological test should be described with numerical data as a general rule, but when the result cannot be described with the numerical data due to the nature of the pharmacological test system, an objective description equivalent to the numerical data for example, a description of the objective observation result by a medical doctor may be accepted. Furthermore, a clinical test, an animal experiment, and in-vitro test are employed as the pharmacological test system.

Therefore, in order for any data present in a specification to be considered as enabling a claimed use, usually points (i)–(iv) should be fulfilled for a representative number of compounds.

However, there has been relatively promising development where the IP High Court has carved a small but significant exception against this per se rule of disallowing postfiling data, at least insofar as in the context of showing inventive step. In particular, the IP High Court overturned the JPO’s decision in allowing later-filed comparative experimental data for understanding the inventive step over the cited reference even though no concrete data demonstrating the superior effects in comparison with the known sunscreen composition were disclosed in the specification as filed. The IP High Court agreed to consider the experimental data submitted after filing of a patent application when a person skilled in the art can understand that the invention exhibits the superior effects from the original description even if any concrete (experimental) data of the activity is not disclosed in the original description [12].

There is another IP High Court decision where the Court reversed another JPO decision that rejected a patent claim directed to the use of flibanserin to treat sexual disorders due to a failure to meet the written-description requirement. The Court observed that in the case where the specification does not disclose a specific process of demonstrating whether technical matter described in the Detailed Description of the Invention is certain, when judging whether requirements under Section 36(4)(i) are met, a conclusion should be reached based on whether or not those skilled in the art can understand the technical meaning of the claimed invention, for example, a problem to be solved by the claimed invention and means to solve the problem and the like, and carry out the claimed invention as of the filing date with collectively considering all the circumstances, even if there is no specific description in the specification [13].

Practitioners may use these arguments as they seek to extend the spirit of the Court’s reasoning in these recent decisions to the broader enablement or written description rejections.

5. Novelty and grace period

Japan requires absolute novelty for a pharmaceutical composition to be patented. As of April 1, 2012, virtually any disclosure, including ‘inventions made public at meetings and seminars, which are not academic conference designated by the Commissioner of the Japan Patent Office, inventions made public on TV, internet and radio, and inventions made public through sales, can enjoy the grace period against such novelty destroying’ acts. The grace period patent application against the inventor’s own novelty destroying acts must be made at the time of filing the application with the JPO. It is also possible to claim a grace period against a publication that has been made against the will of the inventor.

6. Selection invention

Japan does recognize selection inventions where an invention with a generic concept is expressed in a cited reference, an invention with more specific concept selected from the generic concept is called ‘selection invention’, if it is novel over the generic invention and pertains to a technical field in which an effect of a product is difficult to understand from its structure. A selection invention possesses inventive step, when it generates an advantageous effect, not disclosed in a cited reference, qualitatively different or qualitatively the same but quantitatively prominent in comparison with that of an invention with a generic concept in a cited invention, neither of the effect being foreseen by a person skilled in the art from the state of the art [14]. Such selection invention analysis is also extended to life science-related inventions.

7. Obviousness

The obviousness standard in Japan is different from in the US. Structural nonobviousness per se is insufficient. Under Japanese patent practice, the applicant must show that the claimed invention has significant effects that could not have been expected from the prior art or that there was undue difficulty encountered in obtaining the claimed invention, even using a well-known technique, or that one skilled in the art would not have reasonably expected to obtain the claimed invention. Furthermore, even though a particular combination of elements may be structurally nonobvious, the JPO will still take the position that it would be obvious for one skilled in the art to conduct routine variation based on the prior art and achieve the invention without any significant difficulty. Significant effects relied upon to establish nonobviousness of a claimed invention must be present in the application as originally filed. The IP High Court held that if the specification as originally filed fails to specifically describe actual pharmacological effects of a claimed invention, such disclosure cannot be used as a cited reference with regard to obviousness [15].

8. Product-by-process claims

In the landmark case relating to a drug class of statins, a clear interpretation of ‘product-by-process’ claims in Japan was confirmed by the IP High Court that held that the description of a process in a claim limits its scope in the absence of proof that a definition of the product without a description of its production process was impossible or difficult at the time of filing the patent application [16].

The IP High Court clarified the criterion with respect to the interpretation of a product-by-process claim. The scope of a patent claim should be determined by the terms stated in a claim. Therefore, if a process of production is stated in a claim, the scope of the claim should, in principle, be limited by such process of production. However, the IP High Court further noted that in terms of product-by-process claims, there are two categories:

i) An authentic product-by-process claim: which is a claim that specifies or identifies a product by its process of production because it is impossible or difficult to directly specify or identify the product by its structure or feature at the time of filing the patent application.

ii) A pseudo product-by-process claim: which is a claim that describes the process of producing a product despite the fact that it is not impossible or difficult to directly specify or identify the product based on its structure or feature at the time of filing the patent application.

When a product-by-process claim falls within the scope of an authentic product-by-process Claim, the claim should be interpreted to cover the products that are identical to a product produced by the process described in the claim, regardless of the process by which they are produced. On the other hand, the scope of an unauthentic product-by-process claim is limited to the product produced by the process described in the claim.

Furthermore, the IP High Court clearly states that, in terms of the burden of proof in patent infringement cases, a person who claims that the claim falls the scope of an authentic product-by-process claim bears the burden of proof as to whether it was impossible or difficult to directly specify or identify a product by its structure or feature at the time of the filing of the patent application. This decision will grant greater clarity and certainty to life sciences market players in analyzing freedom to operate in view of Japanese patents that have product by process claims.

9. Patent term extension for regulatory approval delays

Patent term extension is only available if the granted patent cannot be worked because regulatory delay in obtaining marketing approval from the Japanese Ministry of Health, Labor and Welfare. Japan does not have the US-style patent term adjustment system to compensate for patent prosecution delays at the patent office.

10. Invalidation

Anyone (there is no standing or controversy requirement) seeking to invalidate a patent may file an Invalidation Appeal against a granted patent at any time at the JPO [17]. However, in 2015, a postgrant review opposition procedure is expected to come into force where parties can file an opposition against granted patents [18].

11. Infringement and clinical trial immunity

Japan recognizes direct and indirect patent infringement. Doctrine of equivalents infringement is also recognized in Japan under applicable conditions [19]. Clinical trials for regulatory approval are exempt from patent infringement [20]. Section 69(1) Patent Law provides a research or experimental use exemption from patent infringement; however, this does not encompass economic or commercial research (conducted by any party including universities) [21].

12. Inventor remuneration

Japanese patent law provides a broad protection for inventors to seek remuneration in the course of their employment relationship and this covers inventors in the life sciences field as well. Pursuant to Section 35(1) of the Japanese patent law, a nonexclusive license of an employee’s invention is created provided that the invention falls within the scope of the business of the employer and is within the scope of the employee’s duties. It is not possible to contract out of this provision.

Amendments were made to Section 35 of the Japanese patent law, effective from April 1, 2005, which ensured that any agreement made between an employer and employee should be enforceable, to the extent that it is ‘unreasonable’. The effect of these amendments is that employers are able to go to some lengths to ensure certainty as to a maximum amount awarded to an employee in a separate agreement, although it will also be held to the same scrutiny as the employment agreement in terms of ‘reasonableness’. Further, if the employment contract is made pre-1995, but the filing date of the patent is post-April 1, 1995, then the post-April 1, 1995, amendments will apply.

The issue of inventor compensation in pharmaceutical litigation was addressed over an invention directed to an anticoagulant where a disgruntled inventor successfully sued his Japanese pharmaceutical employer for reasonable compensation, but the IP High Court of Japan lowered the overall quantum of the award in view of level of contribution of the inventor to the overall clinical and commercial success of the drug in terms of respective patents directed to the compound and the use of said compound [22]. Companies should always be mindful of inventor compensation when dealing with Japanese inventions.

13. Conclusion

Although life science therapeutic inventions are patentable subject matter under Japanese patent law, there are nuanced obviousness and enablement challenges under Japanese patent law that can be surmounted in view of some encouraging Japanese court developments in fostering a pro-patent applicant environment in the life sciences therapeutic patent field. Nevertheless, great care must be taken when drafting and prosecuting such patent applications in the world’s second most important life sciences therapeutic market [23].

Declaration of interest

The author has no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.