FDA Approves Expansion of Angiomax(R) (Bivalirudin) Label to Include Patients with or at Risk of HIT/HITTS Undergoing PCI; HIT/HITTS Places Patients at Higher Risk of Life-Threatening Complications.

PARSIPPANY, N.J. -- The Medicines Company (NASDAQ: MDCO) today announced that the U.S. Food and Drug Administration (FDA) approved the use of Angiomax(R) (bivalirudin) in patients with or at risk of HIT/HITTS -- heparin-induced thrombocytopenia (HIT) and thrombosis syndrome (HITTS) -- undergoing percutaneous coronary intervention (PCI).

HIT/HITTS is a complication of heparin administration that can have devastating clinical consequences for patients, including limb amputation, renal failure and even death.

"We hope to continue demonstrating that replacing heparin with Angiomax leads to better outcomes, particularly in high risk patients, such as those with HIT/HITTS," said John Kelley, The Medicines Company's President and Chief Operating Officer. "The updated Angiomax label will allow for broader dissemination of information to interventional cardiologists and, now, hematologists regarding the role of Angiomax in this high-risk patient population. HIT/HITTS is not well understood in clinical practice and we are planning a future registry study in hospitals to further evaluate Angiomax in this setting."

This Angiomax label expansion is the second in 2005. In June, the label was expanded to include PCI in addition to patients undergoing percutaneous transluminal coronary angioplasty (PTCA). This most recent label expansion includes results from the AT-BAT trial of 51 patients with HIT/HITTS undergoing PCI.

In addition to the risks associated with HIT/HITTS in patients undergoing PCI, a recent study reported by Aurora St. Luke's Medical Center of Milwaukee, Wisconsin showed that the mere presence of heparin antibodies poses an independent risk for potential serious complications following cardiac surgery. These findings highlight that even those patients who did not develop HIT/HITTS, but tested positive for the heparin antibodies, were at a higher risk of postoperative complications. These data were presented on November 1 at the 2005 Annual Meeting of the American College of Chest Physicians.

The Medicines Company is also evaluating the use of Angiomax in the recently completed CHOOSE trials of patients with or at risk of HIT/HITTS undergoing cardiac surgery. The Company anticipates submitting an application to the FDA seeking to include patients with or at risk of HIT/HITTS undergoing cardiac surgery into the Angiomax label.

About Heparin-Induced Thrombocytopenia and Thrombosis Syndrome

Heparin-induced thrombocytopenia (HIT) is an immune-mediated complication of heparin administration that contraindicates further heparin exposure. HIT/HITTS occurs with a reported frequency of approximately 1-5% depending on population and type of heparin received; however, the reported frequency is increasing due to better recognition of the condition and more frequent testing for antibodies. HIT syndrome involves a decrease in circulating platelets (thrombocytopenia) and an increased tendency to form blood clots, which can have devastating clinical consequences such as limb ischemia requiring amputation (10-20%), myocardial infarction, stroke, pulmonary embolism and even death (20-30%). Angiomax has no structural similarity to heparin, does not cross react with heparin antibodies and has a low potential to be immunogenic.

About Angiomax

Angiomax is currently approved in the U.S. and the European Union, as well as several other territories. Angiomax is a direct thrombin inhibitor with a naturally reversible mechanism of action. In clinical trials, Angiomax has demonstrated reductions in both ischemic and bleeding complications compared to heparin as the foundation anticoagulant in the contemporary catheterization lab setting. These reductions in ischemic and bleeding complications remain evident even in high-risk patients.

In the U.S., Angiomax is indicated for use as an anticoagulant in patients with unstable angina undergoing percutaneous transluminal coronary angioplasty (PTCA) and with provisional GPIIb/IIIa inhibition in patients undergoing PCI. Angiomax is also indicated in patients with, or at risk of, HIT/HITTS undergoing PCI. Angiomax is intended for use with aspirin. The most common adverse events for Angiomax in clinical trials comparing Angiomax and heparin were back pain, pain, nausea, headache, and hypotension. The incidence of these adverse events was comparable in both the Angiomax and heparin groups in these trials. An unexplained fall in blood pressure or hematocrit, or any unexplained symptom, should lead to serious consideration of a hemorrhagic event and cessation of Angiomax administration. Angiomax is contraindicated in patients with active major bleeding or hypersensitivity to Angiomax or its components. Please see full prescribing information available at http://www.angiomax.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 anti-clotting therapy approved in the U.S. and other countries for use in patients undergoing coronary angioplasty, a procedure to clear restricted blood flow in arteries around the heart. The Medicines Company creates value using its range of clinical and commercial skills to develop products acquired from leading life science innovators. The Company's website is http://www.themedicinescompany.com.

Statements contained in this press release about The Medicines Company and Angiomax that are not purely historical, and all other statements that are not purely historical, may be deemed to be forward-looking statements for purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. Without limiting the foregoing, the words "believes," "anticipates" and "expects" and similar expressions are intended to identify forward-looking statements. These forward-looking statements involve known and unknown risks and uncertainties that may cause the Company's actual results, levels of activity, performance or achievements to be materially different from those expressed or implied by these forward-looking statements. Important factors that may cause or contribute to such differences include the extent of the commercial success of Angiomax, physicians' acceptance of Angiomax clinical trial results, whether the Company's products will advance in the clinical trials process, whether clinical trial results will warrant submission of applications for regulatory approval, whether the Company will be able to obtain regulatory approval for additional indications of Angiomax and such other factors as are set forth in the risk factors detailed from time to time in the Company's periodic reports and registration statements filed with the Securities and Exchange Commission including, without limitation, the risk factors detailed in the Company's Quarterly Report on Form 10-Q filed on November 8, 2005, which are incorporated herein by reference. The Company specifically disclaims any obligation to update these forward-looking statements.