Umezu founded the company in 1992, turning it into one of Japan's most respected healthcare specialist agencies.
Eli Lilly is a key client; Office also works for a cross section of major pharmaceutical companies, many of whom are already Grey Healthcare clients.
Chris Beaumont, president and CEO of Grey Japan, said: "Healthcare is a growing part of the communication industry and has considerable potential for growth. Increasing deregulation, a rapidly aging population profile, and more emphasis on the prevention of illness are all very positive factors for this sector."
Grey Healthcare buys Office MIT; names new CEO
Grey Healthcare Group has acquired Office MIT, a medical education company based in Tokyo. Hisa Umezu, founder and president of Office MIT, has been named president and CEO of Grey Healthcare Japan.