The Japanese Ministry of Health, Labor and Welfare began accepting submissions for new product approvals as of July 1, 2001. After one year the experimental grace period expired. Since July 1, 2003 all new submissions have been required to be in CTD format. Japan has yet to establish any eCTD guidance yet, though they currently accept eCTD submissions. According to the Proceedings of the International Conference on Harmonization Tokyo Symposium, the country has received 52 eCTD applications as of 2007.
Japan's Pharmaceuticals and Medical Devices Agency (PMDA) has not issued eCTD guidance in English. It's best to confer with a Japanese-speaking colleague or partner before initiating eCTD planning for Japan.
Regulatory guidance and information from Japanese authorities and associations are summarized in a selection of documents highlighted below: