Life Sciences Horizons Brochure 2025 - Flipbook - Page 70
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2025 Horizons Life Sciences and Health Care
Patent litigation rising in Japan as linkage system evolves
In Japan, “originator versus generics” patent litigation
cases continue to rise, and we expect the nonstatutory “patent linkage” system to evolve further in
2025 and beyond, especially in respect of the grant of
marketing authorizations for generic products.
In essence, Japan’s “patent linkage” system delays the grant of
marketing authorizations for a generic product until there are
no relevant originator patents covering such product (due to
the relevant patents expiring or being invalidated). The main
objective of the system is to prevent potential disruption to
a stable supply of pharmaceutical products to the Japanese
market, which may occur, for example, if an originator company
successfully obtains an injunction against an approved generic
product through patent infringement proceedings.
Recent issues have related to the nature of “relevant originator
patents” – which has generally been understood to mean patents
that cover, for instance, the active ingredient or a specific
indication – and the regulator’s apparent readiness to grant
generic marketing authorization in certain cases. Notably, we
understand that the regulator may reach its own view on the scope
of originator patents, and does not examine their patentability,
which can potentially lead to complications.
Unlike other jurisdictions, Japan’s patent linkage system is
based on notifications from the government, which creates
both flexibility and uncertainty from which a number of generic
companies appear to have benefited in the past few years. In
particular, the regulator recently approved generic versions of two
or more drugs the active ingredients of which may still have been
protected by relevant patents or patent term extensions. In one
case, a preliminary injunction order was granted promptly after
the grant of such generic marketing authorization; at least one
other case is ongoing. Once those cases are fully resolved, there
may be important changes to the regulator’s practice in the future
in favor of originators and patentees, and also potentially
regarding the scope of patent term extensions.
Finally, we have observed a number of biologics and biosimilar
patent cases continuing to be the subject of dispute resolution
in Japan, somewhat mirroring cases in the U.S. and Europe. It
remains unclear whether the Japanese courts will take similar
positions on these issues to courts’ conclusions elsewhere. For
instance, regarding antibody patenting, Japan’s current approach
appears to be more similar to Europe’s than to the position taken
in the U.S., in that the Japan Patent Office tends to focus on the
new functions or properties of a claimed antibody in determining
“inventiveness” or “non-obviousness”. Notably, expert evidence
seems to have made a significant contribution in certain disputes.
We expect that the number of biologics patent cases will increase
in coming years, and therefore suggest carefully tracking and
analyzing the practical implications of relevant changes as
they arise.
Dr. Frederick Ch'en
Office Managing Partner
Tokyo
