The Medicines Company To Provide Financial Guidance for 2004 on December 17 Webcast.

Business Editors

PARSIPPANY, N.J.--(BUSINESS WIRE)--Dec. 4, 2003

The Medicines Company (NASDAQ:MDCO) has scheduled its annual conference call to discuss financial guidance for 2004. A webcast presentation will be held on Wednesday, December 17, 2003, at 5:00 p.m. Eastern Time.

The presentation will be webcast by CCBN and can be accessed at The Medicines Company's web site (http://www.themedicinescompany.com). To listen to audio only: dial 800-472-8325 and request The Medicines Company's 2004 guidance call. From outside United States: dial 1-706-679-0816. Replay available for two weeks following call: 800-642-1687. Replay outside the U.S.: 1-706-645-9291. Replay passcode: 4394852.

The webcast is also being distributed over CCBN's Investor Distribution Network to both institutional and individual investors. Individual investors can listen to the call through CCBN's individual investor center at www.companyboardroom.com or by visiting any of the investor sites in CCBN's Individual Investor Network. Institutional investors can access the call via CCBN's password-protected event management site, StreetEvents (www.streetevents.com).

About The Medicines Company:

The Medicines Company meets the demands of the world's most advanced medical practitioners by developing products that improve acute hospital care. The Company markets Angiomax(R) (bivalirudin), an anticoagulant approved in the United States and other countries for use in patients undergoing coronary angioplasty procedures. The Medicines Company creates value using its range of clinical and commercial skills to develop products acquired from leading life science innovators.