The MSSO - Maintenance and Support Services Organization - serves as the repository, maintainer, and distributor of MedDRA as well as the source for the most up-to-date information regarding MedDRA and its application within the biopharmaceutical industry and regulators. MedDRA subscribers submit proposed changes to the terminology. The MSSO includes a group of internationally based physicians who review all proposed subscriber changes and provide a timely response directly to the requesting subscriber.
Please visit the MSSO website (http// or contact the MSSO Help desk (

JMO - Japanese Maintenance Organization - is a partner of the MSSO. JMO provides MedDRA support to companies headquartered in Japan as well as maintaining and distributing MedDRA/J. The JMO assists the MSSO in providing MedDRA-related information and services in Japan.

The responsibilities of the JMO are to maintain MedDRA in the Japanese language (MedDRA/J) synchronized with the English version, and to distribute and to promote the standardized utilization in Japan.
If you have any question regarding MedDRA Japanese version or MedDRA utilization in Japan, please do not hesitate to contact the JMO .