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):  July 20, 2004



                              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)







Item 12.  Disclosure of Results of Operations and Financial Condition.

         On July 20, 2004, The Medicines Company (the "Company") announced its
financial results for the quarter ended June 30, 2004. The full text of the
press release issued in connection with the announcement is attached as Exhibit
99.1 to this Current Report on Form 8-K.

         The information in this Current Report on Form 8-K and the Exhibit
attached hereto 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.





                                   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:  July 20, 2004            By:  /s/ Steven H. Koehler
                                     ---------------------
                                     Steven H. Koehler
                                     Vice President and Chief Financial Officer






                                  Exhibit Index


Exhibit No.           Description
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99.1                  Press release dated July 20, 2004 entitled "The Medicines
                      Company Reports Second Quarter and First Half 2004
                      Financial Results."