Examination Guidelines for Patent Applications Relating to Pharmaceutical Inventions in the Japan Patent Office

In 2005, the Japan Patent Office issued Examination Guidelines for Pharmaceutical Inventions, which mainly focus on enablement/written description requirements, novelty and inventive step.The Examination Guidelines also address the issue of patentability of combination drugs and dosing schedule.

(a) A pharmacological agent for the treatment of disease A comprising compound X.
(b)A pharmaceutical composition for treating disease A comprising compound X.
(c) A drug for treating disease A comprising compound X.
(d) Use of compound X in manufacturing a pharmaceutical composition for use in the treatment of a patient with disease A.
(e) Compound X for treating disease A. (*not regarded as medical use claim)

NOTE: Generally, claims have to recite the diseases to be treated and the active ingredients.  However, reciting specific name of disease is not always necessary if the medical use can be clearly understood in the light of the specification.  For example, a recitation “for treating heart disorders” or “for inhibiting histamine release” may be acceptable.  Swiss-style claims are also acceptable to the patent office. In contrast, claims drawn to compounds with intended medical uses are recognized as “chemical compound claims” and the medical use limitations will be disregarded in the examination of the patentability.

The application must establish the feasibility of the claimed compounds to treat the diseases.
In order to establish the feasibility, pharmacological test data or the equivalent have to be disclosed in the specification as filed.

NOTE: The Japan Patent Office strictly requires that patent applications claiming medical uses (pharmaceutical inventions) should disclose “pharmacological test data or the equivalent” in the specifications as filed.  If the data are not disclosed in the specification, the application may be rejected as not satisfying the enablement/written description requirements on the ground that the specification is not considered to sufficiently describe the claimed subject matter in such a way as to reasonably convey to one skilled in the relevant art that the inventors, at the time the application was filed, had possession of the claimed invention (Art. 36 (4) and Art. 29 (2) of the Patent Law). Moreover, the patent office does not accept any late submission of the pharmacological test data after the filing of the application.

Case No.: Hei-8 (Gyou-ke) 201
“The Patent Law provides that the claimed invention has to be sufficiently and clearly described in the specification in such a manner that the invention can easily be carried out by those skilled in the art.
… Accordingly, the specification cannot be said  to sufficiently describe the invention of an anti-nausea drug if the actual anti-nausea effect of the claimed compound is not understood from the descriptions in the specification even in view of the state of the art as of the filing date.  The fact that the actual effect was demonstrated after the filing date, could not restore the failure in the specification as filed.”

NOTE: The Tokyo High Court (presently the IP High Court) has also upheld this practice (Case No.: Hei-8 (Gyou-ke) 201).
In our experience, the patent office does not recognize in vitro test data as “pharmacological test data or the equivalent” and the office only appreciates in vivo test data on the premise that a number of compounds shown to have in vitro biological activity fail to show any medical effect when actually administered to humans/animals.  In view of this, if the specification as filed solely discloses in vitro test data, additional submission of a prior art reference demonstrating that in vitro tests are a valid and reliable method in evaluating the actual medical effect is necessary.