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                                                                    EXHIBIT 23.1

                       CONSENT OF INDEPENDENT ACCOUNTANTS

    We hereby consent to the inclusion in this Registration Statement on Form
S-1 of our report dated February 25, 2000, except for Note 11, as to which the
date is July 21, 2000, and Note 12 as to which the date is August 24, 2000,
relating to the financial statements of AeroGen, Inc. (a company in the
development stage) at December 31, 1998 and 1999, for each of the three years
ended December 31, 1999 and for the cumulative period from November 18, 1991
(date of inception) to December 31, 1999, which appear in such Registration
Statement. We also consent to the references to us under the headings "Experts"
in such Registration Statement.

PricewaterhouseCoopers LLP

San Jose, California
August 25, 2000
