UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  December 17, 2012

The Medicines Company

(Exact Name of Registrant as Specified in Charter)

Registrant’s telephone number, including area code:  (973) 290-6000

Not applicable.

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

¨            Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨            Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨            Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨            Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01.  Regulation FD Disclosure.

Beginning on December 17, 2012, senior executives of The Medicines Company (the “Company”) will deliver a presentation as part of a non-deal roadshow with investors. A copy of the presentation materials being delivered by the Company are attached to this current report as Exhibit 99.1.

The information furnished pursuant to Item 7.01 of this current report, including Exhibit 99.1, shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise subject to the liabilities of that Section. As such, this information shall not be incorporated by reference into any of the Company’s reports or other filings made with the Securities and Exchange Commission. The furnishing of the information in this current report is not intended to, and does not, constitute a determination or admission by the Company that the information in this current report is material or complete, or that investors should consider this information before making an investment decision with respect to any security of the Company.

Forward Looking Statements

This current report includes forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended. For this purpose, any statements contained herein regarding the Company’s strategy, future operations, prospects, plans and objectives of management, other than statements of historical facts, are forward-looking statements. The words “anticipates,” “believes,” “estimates,” “expects,” “intends,” “may,” “plans,” “projects,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. The Company cannot guarantee that it actually will achieve the results, plans, intentions or expectations expressed or implied in the Company’s forward-looking statements. There are a number of important factors that could cause actual results, levels of activity, performance or events to differ materially from those expressed or implied in the forward-looking statements the Company makes. These important factors include the factors set forth in the Company’s Quarterly Report on Form 10-Q filed on November 9, 2012, which are incorporated herein by reference. The Company specifically disclaims any obligation to update these forward looking statements.

Item 9.01 Financial Statements and Exhibits

(d) Exhibit

The following exhibit is furnished as part of this current report on Form 8-K:

Exhibit 99.1 — The Medicines Company Non-Deal Roadshow Presentation.

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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Exhibit Index

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