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):  February 22, 2005


                              The Medicines Company
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               (Exact Name of Registrant as Specified in Charter)


          Delaware                     000-31191                 04-3324394
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(State or Other Jurisdiction          (Commission              (IRS Employer
      of Incorporation)               File Number)          Identification No.)


           8 Campus Drive
       Parsippany, New Jersey                                     07054
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(Address of Principal Executive Offices)                        (Zip Code)

Registrant's telephone number, including area code: (973) 656-1616



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          (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 2.02.     Results of Operations and Financial Condition.

     On February 23, 2005, The Medicines  Company (the "Company")  announced its
financial  results for the quarter and year ended  December 31,  2004.  The full
text of the  press  release  issued  in  connection  with  the  announcement  is
furnished as Exhibit 99.1 to this Current Report on Form 8-K.

     The  information  in this Form 8-K  (including  Exhibit  99.1) shall not be
deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934
(the "Exchange  Act") or otherwise  subject to the  liabilities of that section,
nor  shall it be  deemed  incorporated  by  reference  in any  filing  under the
Securities  Act of 1933 or the Exchange  Act,  except as expressly  set forth by
specific reference in such a filing.

Item 5.02.     Departure  of  Directors  or  Principal  Officers;   Election  of
               Directors; Appointment of Principal Officers

     On February 22, 2005,  the Board of Directors  (the "Board") of the Company
elected John P. Kelley to the Board. Mr. Kelley has been the Company's President
and Chief Operating Officer since December 1, 2004.

     On  February  22,  2005,  James E.  Thomas,  a member  of the  Board  since
September  1996,  announced  his  resignation  from the Board.  Mr. Thomas was a
member of the Compensation Committee of the Board.

Item 9.01.     Financial Statements and Exhibits

       (c)          Exhibits

                    The following  exhibit relating to Item 2.02 shall be deemed
                    to be furnished, and not filed:

                    99.1   Press  Release   dated   February  23,  2005 entitled
                           "The Medicines  Company  Reports  Fourth  Quarter and
                           Year 2004 Financial Results."

                                   SIGNATURES


     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.

                                       THE MEDICINES COMPANY


Date:  February 23, 2005               By: /s/ Steven H. Koehler
                                           ---------------------
                                           Steven H. Koehler
                                           Senior Vice President and Chief 
                                           Financial Officer

                                  Exhibit Index


Exhibit No.         Description
-----------         -----------

99.1                Press  release   dated   February  23,  2005  entitled  "The
                    Medicines  Company  Reports  Fourth  Quarter  and Year  2004
                    Financial Results."