Toshiyasu ISHIOKA, Ph.D.


Partner, Patent Attorney

ToshiyasuIshiokaWebToshiyasu Ishioka received his PhD from the University of Tokyo in apoptosis-associated proteins and completed his postdoctoral research at the Cell Growth and Regulation Laboratory, Institute of Molecular and Cellular Bioscience at the University of Tokyo.
Dr. Ishioka’s broad knowledge of pharmaceutical sciences, based on a deep understanding of pharmaceuticals and organic chemistry, molecular biology, cell biology, and biochemistry is a great asset in many situations, including prosecution of patents, infringement lawsuits, and license negotiations. He is also an expert in patent term extension. He joined the firm in 2006.


Chemistry, Organic Chemistry, Medicinal Chemistry, Small Molecules, Biotechnology, Molecular Biology, Biochemistry, Pharmaceuticals, Diagnostics, Patent Term Extension


  • PhD, Medical Pharmaceutics, Pharmaceutical Science The University of Tokyo
  • MS, Medicinal Chemistry, Pharmaceutical Science The University of Tokyo
  • BS, Pharmaceutical Science The University of Tokyo


  • Toshiyasu Ishioka "How life sciences innovators can avoid patent term extension pitfalls in Japan" IAM Life Science, March 30, 2020.
  • Toshiyasu Ishioka “Decision of grand panel of intellectual property High Court regarding scope of protection of patent term extension” Lexology, February 9, 2017.
  • Katayama, R., Ishioka, T., Takada, S., Takada, R., Fujita, N., Tsuruo, T., and Naito, M. “Modulation of Wnt signaling by the nuclear localization of cellular FLIP-L.” J. Cell Sci. 2010. 123 (Pt 1): 23-8.
  • Ishioka, T., Katayama, R., Kikuchi, R., Nishimoto, M., Takada, S., Takada, R., Matsuzawa, S., Reed, J. C., Tsuruo, T., and Naito, M. “Impairment of the ubiquitin-proteasome system by cellular FLIP.” 2007. Genes Cells 12 (6): 735-44.
  • Naito, M., Katayama, R., Ishioka, T., and Tsuruo, T. “Apoptosis Sogai Tanpakushitsu no Kinou to Gan. [Function of Apoptosis Inhibitor Protein and Cancer.]” Shujunsha, Saibo Kogaku, 2005. 24 (9), 921-924.
  • Naito, M., Katayama, R., Ishioka, T., Suga, A., Takubo, K., Nanjo, M., Hashimoto, C., Taira, M., Takada, S., Takada, R., Kitagawa, M., Matsuzawa, S., Reed, J. C., and Tsuruo, T. “Cellular FLIP inhibits beta-catenin ubiquitylation and enhances Wnt signaling.” Mol. Cell. Biol. 2004. 24 (19): 8418-27.
  • Hao, Y., Sekine, K., Kawabata, A., Nakamura, H., Ishioka, T., Ohata, H., Katayama, R., Hashimoto, C., Zhang, X., Noda, T., Tsuruo, T., and Naito, M. “Apollon ubiquitinates SMAC and caspase-9, and has an essential cytoprotection function.” Nat. Cell Biol. 2004. 6 (9): 849-60.
  • Ishioka, T., Tanatani, A., Nagasawa, K., and Hashimoto, Y. “Anti-androgens with full antagonistic activity toward human prostate tumor LNCaP cells with mutated androgen receptor.” Bioorg. Med. Chem. Lett. 2003. 13 (16): 2655-8.
  • Ishioka, T., Kubo, A., Koiso, Y., Nagasawa, K., Itai, A., and Hashimoto, Y. “Novel non-steroidal/non-anilide type androgen antagonists with an isoxazolone moiety.” Bioorg. Med. Chem. 2002. 10 (5): 1555-66.


  • Japanese (native)
  • English


  • Japan Patent Attorneys Association (JPAA)
  • The Japanese Cancer Association (JCA)
  • The Pharmaceutical Society of Japan
  • Pharmacist License


  • ”The Current State of Opposition in Japan: Statics and Our Recommendations", Patent Information Annual Conference (PIAC), 5 September 2017, Beijing
  • "Reasons for Rejection in Japan and How to Respond", Technology Export Research Roundtable (hosted by the Zhongguancun Science Park (Z-Park) Administrative Committee with the assistance of the Beijing Adminstration of Foreign Affairs), 9 September 2015, Beijing (invited speaker)