How can we specify the second use drugs from patent information?: R&D on the second use drugs may lead to further development of pharmaceutical industries

Needless to say, it is not easy to develop new drugs because of huge amount of investment on R&D. For the pharmaceutical companies, which have difficulty to enter into new drugs development, it will be one of the opportunities to make R&D to find the second use of commercialized drugs. The second use drugs are known as the drugs which its new effects have been found out after the original drugs and the new effect shall be different from the original effects. The result of R&D of the second use drugs can be patented as use claims depending on its inventive step. However, it is not easy to specify which patent claim is the second use drug, and there are no well-established methods to identify them. So, in this research we will propose the way to identify them with patent information by using the variation of IPCs, the description of patent claims, and the joint applicants. Then, for the collected second use drugs' patent information based on the proposed method, we made analysis of the situation of R&D strategy targeting the second use drugs, as an example, Takeda Pharmaceutical Company Limited. We believe the proposed method and the results of empirical study will contribute to further growth of pharmaceutical companies by defining R&D strategy which is well balanced developments between new drugs and the second use drugs.