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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 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,
Michael N. Avallone, Vice President - Finance and Chief Financial Officer 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/ Michael N. Avallone
                            --------------------------
                            Michael N. Avallone
                            Vice President - Finance and Chief Financial Officer
                            December 10, 2004