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                                                                    EXHIBIT 32.1

                            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 of Advanced Magnetics, Inc. (the
"Company") on Form 10-K for the period ending September 30, 2004 as filed with
the Securities and Exchange Commission on the date hereof (the "Report"), I,
Jerome Goldstein, Chairman of the Board of Directors, President, Chief Executive
Officer and Treasurer of the Company, certify, pursuant to 18 U.S.C. Section
1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002,
that, to my knowledge:

     (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.


                                         /s/ Jerome Goldstein
                                      -----------------------------------
                                      Jerome Goldstein
                                      Chairman of the Board of Directors,
                                      President, Chief Executive Officer
                                      and Treasurer
                                      December 10, 2004