1 EX - 21 SUBSIDIARIES OF THE REGISTRANT EXHIBIT 21 SUBSIDIARIES OF MILLENNIUM PHARMACEUTICALS, INC. NAME OF SUBSIDIARY JURISDICTION OF ORGANIZATION Millennium BioTherapeutics, Inc. Delaware Millennium Predictive Medicine, Inc. Delaware Millennium Information, Inc. (1) Delaware (1) In January 1999, Millennium Information, Inc. was merged with Millennium Predictive Medicine, Inc. Millennium Predictive Medicine, Inc. was the surviving corporation of the merger.