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                                                                    EXHIBIT 99.1

PRESS RELEASE

              MICROCIDE PHARMACEUTICALS ANNOUNCES CEO TO STEP DOWN

                    James E. Rurka to Continue as a Director

     Mountain View, CA, March 22, 2001 /PRNewswire/ -- Microcide
Pharmaceuticals, Inc., (Nasdaq: MCDE), today announced that James E. Rurka will
step down as its President and Chief Executive Officer upon the hiring of a
successor, while continuing as a member of the Board of Directors. An executive
search is underway with Korn/Ferry International.

     "We have made significant progress with our forward integration strategy of
moving from a drug discovery focus to a strong emphasis on drug development, and
we're now at the point of having five potential product candidates emerging from
our three technology platforms. At this time, however, I have concluded that new
day-to-day leadership will enhance Microcide's ability to move forward through
the next steps of its drive to put more drug candidates into the clinic," said
Jim Rurka, President and CEO. "I will therefore step down as President and CEO
when the Board of Directors names a successor, and will then continue to
contribute in any way I can to Microcide's future success as an active member of
the Board."

     "During the seven years of Jim's leadership, Microcide has positioned
itself as the premier anti-infective research company in all of Biotech,"
commented John Walker, Chairman of the Board. "The Board accepts Jim's decision
that a change in leadership will help propel the Company in its next phase of
growth, and looks forward to working with him in his role as a Director, in
identifying our new CEO, and in supporting all of the people at Microcide in
realizing our potential."

     Mr. Rurka joined Microcide as President and CEO and a Director in February,
1994. He has led the Company through a second round private financing, the
signing of three major pharmaceutical company collaborations, an Initial Public
Offering in May, 1996, and the subsequent evolution of the Company to a
broad-based antimicrobial drug discovery and development enterprise.

     Microcide is a biopharmaceutical company committed to the discovery,
development and commercialization of novel antimicrobials for the improved
treatment of serious bacterial, fungal and viral infections. The Company's three
discovery research platforms address the growing problems of antibiotic
resistance and the need for improved antifungal and antiviral therapeutics. The
Company's Cephalosporin Antibiotics and Efflux Pump Inhibition platforms focus
on developing novel antibiotics and antibiotic potentiators (efflux inhibitors)
to directly address existing bacterial and fungal resistance problems.
Microcide's Microbial Genomics platform utilizes proprietary bacterial, fungal
and viral genetics and genomics tools to discover entirely new classes of
antimicrobial agents.

     The statements in this press release that relate to the outcome of research
programs, including drug discovery and development of potential products as well
as the ability to attract and retain key personnel are forward-looking
statements which are subject to the Safe Harbor provisions created by the
Private Securities Litigation Reform Act of 1995. Such forward-looking
statements involve risks and uncertainties that could cause actual results to be
materially different, either better or worse, from those discussed. Factors that
could cause actual results to differ include, but are not limited to, failure of
clinical trials to demonstrate safety and efficacy, inability to raise
additional funds and the ability to attract and retain key personnel. Additional
information concerning these and other factors that could cause such a
difference is contained in Microcide's SEC filings, including its Annual Report
on Form 10-K/A for the year ended December 31, 2000. There can be no assurance
that any appropriate management candidates will be hired, additional equity
capital will be raised or that potential products will successfully proceed
through lead optimization, preclinical development and clinical trials, obtain
requisite regulatory approvals for marketing, and result in a commercially
useful product.

Investor contact: Donald D. Huffman, Chief Financial Officer, 650-428-3557 -
http://www.microcide.com

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