Angiomax(R) (Bivalirudin) Recommended for Use in Percutaneous Coronary Interventions in Updated Guidelines from American College of Cardiology and American Heart Association.

DALLAS -- The Medicines Company

Guidelines Announced at American Heart Association's Scientific Sessions 2005

The American College of Cardiology, American Heart Association, and Society for Cardiovascular Angiography and Interventions have jointly released updated guidelines recommending that the direct thrombin inhibitor Angiomax(R) (bivalirudin) be used in patients undergoing percutaneous coronary interventions (PCI).

Angiomax is granted a Class IIa recommendation (defined as "weight of evidence/ opinion is in favor of usefulness/efficacy") as an alternative to unfractionated heparin and glycoprotein (GP) IIb/IIIa antagonists in non high-risk patients undergoing elective PCI. The guidelines define elective as all PCI procedures other than the emergency use of PCI for patients with ST-segment elevation myocardial infarction (STEMI).

"We believe that inclusion of Angiomax in the guidelines will further accelerate its use in PCI," said John Kelley, President and Chief Operating Officer of The Medicines Company. "The guidelines are evolving and it is a step forward that Angiomax and the REPLACE-2 trial are recognized alongside other advances in PCI practice. Because we have seen favorable outcomes in patients with high risk characteristics in REPLACE-2, we believe the results of the ongoing ACUITY and HORIZONS trials in high-risk ACS patients may support an even stronger recommendation in the next guidelines update."

The new guidelines include a review of data from the REPLACE-2 trial that examined Angiomax performance compared to the combination of heparin with GP IIb/IIIa inhibitors. REPLACE-2 demonstrated effectiveness of Angiomax, while also reducing bleeding when it replaces heparin in PCI patients.

The ongoing ACUITY trial (Acute Catheterization and Urgent Intervention Triage strategy) is studying Angiomax with or without GP IIb/IIIa inhibitors in patients with acute coronary syndromes. HORIZONS is examining Angiomax use in patients defined in the guidelines as high risk, namely, STEMI patients undergoing emergency PCI.

In the guidelines, Angiomax is also granted Class I (defined as "general agreement that a given procedure or treatment is beneficial, useful, and effective") recommendation in patients with heparin-induced thrombocytopenia (HIT) and those with renal failure.

In addition, the guidelines stated that women continue to have increased bleeding and vascular complications compared with men and the use of bivalirudin during elective PCI appears to reduce the risk of bleeding in both women and men compared with unfractionated heparin.

About the Guidelines

The ACC and AHA have jointly produced guidelines in the area of cardiovascular disease since 1980. The latest report, "2005 Guideline Update for Percutaneous Coronary Intervention," is an update of the 2001 practice guidelines based on new research and practice patterns. These guidelines are intended to help physicians in clinical decision-making by recommending multiple approaches for the diagnosis, management and prevention of specific diseases or conditions.

About Heparin-Induced Thrombocytopenia

Heparin-induced thrombocytopenia (HIT) is an immune-mediated complication of heparin administration that contraindicates further heparin exposure. HIT syndrome occurs in about 3% of the patients undergoing cardiac surgery and overt thrombosis occurs in 50% of HIT patients. This condition, which involves a decrease in circulating platelets (thrombocytopenia) and an increased tendency to form blood clots, can have devastating clinical consequences such as limb ischemia requiring amputation (10-20%), myocardial infarction, stroke, pulmonary embolism and even death (20-30%). A recent study found that even the presence of heparin antibodies pose an independent risk of potential serious complications following cardiac surgery.

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 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, Angiomax 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 "believe," "hope," "anticipate" and "expect" 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.