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                                                                    EXHIBIT 32.2

                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report on Form 10-K of NitroMed, Inc. (the
"Company") for the period ended December 31, 2003 as filed with the Securities
and Exchange Commission on the date hereof (the "Report"), the undersigned,
Joseph Grimm, Chief Financial Officer of the Company, hereby certifies, pursuant
to 18 U.S.C. Section 1350, that:

     (1)  The Report fully complies with the requirements of Section 13(a) or
          15(d) of the Securities Exchange Act of 1934; and

     (2)  The information contained in the Report fairly presents, in all
          material respects, the financial condition and results of operations
          of the Company.


Dated: March 30, 2004              /s/ Joseph Grimm
                                   -------------------------------------------
                                   Joseph Grimm
                                   Senior Vice President, Business Development
                                   and Chief Financial Officer, Treasurer and
                                   Secretary
                                   (principal financial officer)