1. Overview

In order to implement an invention related to a medicine or the like, permission should be obtained under the Pharmaceutical Affairs Act, but here, a patentee may suffer the disadvantage of not being able to implement the patented invention in the process of obtaining such permission. In order to remedy such disadvantage and protect and encourage the medicinal inventions, Article 89 (1) of the Korean Patent Act provides a system that extends the duration of patent rights by the period during which the patent invention cannot be implemented, limited to inventions that require a long period of time to obtain permission under the Pharmaceutical Affairs Act, and the like. However, Article 89(1) of the Korean Patent Act and Article 7(1) of the Enforcement Decree of the Old Patent Act does not stipulate the definition of the ‘active part exhibiting the medicinal effect’ or the specific scope of the inclusion thereof.

This article will introduce the Supreme Court decision that comprehensively considers the overall system and purpose of relevant laws, the regulation format and content of the relevant provisions based on the principle of faithfully interpreting the ‘active part showing the medicinal effect,’ the definition or the specific scope of which is not clearly stipulated in the law, according to the usual meaning thereof.

2. Issues

Based on the form and content of the provisions of the Enforcement Decree of this case, as well as the relevant pharmaceutical laws, the ‘active part showing the medical effect’ in the Enforcement Decree of this case denotes ‘the part of the active ingredient of a drug that is active and shows the efficacy and effect as stipulated in the product license of the drug by its inherent pharmacological action.’ On the other hand, there are cases in which a part that is not active in and of itself is combined with the ‘active part showing the medical effect’ of a previously licensed drug and affects the degree of efficacy and effect of the drug.

Peginterferon beta-1a, the active ingredient in the claim of this case (hereinafter referred to as the ‘drug of this case’), is a pharmaceutical invention in which polyethylene glycol (PEG) is covalently bonded to interferon beta-1a and PEGylated. The plaintiff (patentee) filed an application for patent term extension in this case, but the Examiner of the Korean Intellectual Property Office and the Patent Trial and Appeal Board (PTAB) rejected the application and dismissed the plaintiff’s request for a trial to cancel the rejection on the grounds that there is an existing licensed drug containing interferon beta-1a as the active ingredient, and the drug in this case has the same active ingredient that shows the same therapeutic effect as the existing licensed drug, interferon beta-1a, and therefore, is not a new substance.

The Patent Court overturned the PTAB’s decision and stated that “the active part that shows the medical effect of the drug in this case is peginterferon beta-1a, and even if the existing licensed drug containing interferon beta-1a as the active part is considered, the polyethylene glycol bound to the interferon beta-1a is also a new substance with the chemical structure of the active part that shows the medical effect”. That is, the PTAB and the Patent Court have different judgments as to whether the entire combination of a “non-active part” and an “active part showing the medical effect” of an existing licensed drug corresponds to the “active part showing the medical effect” as stated in the Enforcement Decree of this case.

3. Supreme Court Decision

The Supreme Court interpreted the new substance (a substance with a new chemical structure of the active part that shows the medical effect) stipulated in the Enforcement Decree of this case, and held that since the form and content of the provisions of the Enforcement Decree of this case distinguish between the ‘active ingredient’ and the ‘active part that shows the medical effect,’ even if a part that is not active in itself is combined with the ‘active part that shows the medical effect’ to affect the degree of efficacy and effect of the pharmaceutical product, the entire combination cannot be considered as the ‘active part that shows the medical effect’ as stated in the Enforcement Decree of this case, and in light of the intent and purpose of the patent term extension system, it is difficult to consider as an invention subject to the patent term extension a pharmaceutical invention that adds a part that is not active in itself to the known active part of a previously licensed pharmaceutical product to affect the degree of efficacy and effect of the pharmaceutical product.

The Supreme Court concluded that an active ingredient of the drug in this case, which is active in the body and shows the therapeutic effect of relapsing multiple sclerosis through its inherent pharmacological action, is interferon beta-1a, and a polyethylene glycol part bound to interferon beta-1a is only a part that affects the level of activity of interferon beta-1a by allowing the interferon beta-1a to remain in the blood for a longer period of time or by lowering the binding of interferon beta-1a to the protein receptor, while not showing the activity in the body or the therapeutic effect as mentioned above, and therefore, even if the ‘active part that shows the medical effect’ of the drug in this case is interferon beta-1a, and the polyethylene glycol is bound to the ‘active part that shows the medical effect’, interferon beta-1a, to form peginterferon beta-1a, the entire compound, peginterferon beta-1a, cannot be considered as the ‘active part showing the medical effect ’ as stated in the Enforcement Decree of this case, and the interferon beta-1a, which is the ‘active part showing the medical effect’ in the drug of this case, has the same three-dimensional chemical structure as the interferon beta-1a, which is the ‘active part showing the medical effect’ in the previously licensed drug; therefore, the Supreme Court reversed and remanded the case to the lower court, which made a judgment different therefrom.

4. Implications

The Supreme Court decision clarified the meaning of the ‘active part showing the medical effect’ in relation to the patent term extension of the pharmaceutical patents under the Korean Patent Act. Specifically, by clarifying that in cases in which a non-active part is combined, the entire combination cannot be considered to be the ‘active part showing the medical effect,’ a standard for the patent term extension of the pharmaceutical patents has been proposed. This is expected to have a significant impact on pharmaceutical patent policy and the pharmaceutical industry, so that patent attorneys performing patent preparation and prosecution work should be familiar with the Supreme Court decision, and should simultaneously provide accurate examination information to their clients so that the pharmaceutical companies can carefully establish patent management strategies from the patent application stage, and should be guided to prepare for various scenarios to minimize legal risks.