EXHIBIT 99.1

          Cerus Corporation Announces Second Quarter Results


    CONCORD, Calif.--(BUSINESS WIRE)--July 29, 2004--Cerus Corporation
(Nasdaq:CERS) today announced results for the second quarter ended
June 30, 2004.
    The net loss for the second quarter of 2004 was $11.5 million, or
$0.52 per share, compared to a net loss of $16.8 million, or $0.97 per
share, for the second quarter of 2003. During the second quarter of
2004, Cerus reported restructuring costs of $2.5 million related to
its previously announced strategic realignment to reduce expenses and
to increase support of its program to develop therapeutic vaccines
against cancer and infectious disease.
    The overall reduction in the net loss for the quarter was due
primarily to increased funding received under cooperative agreements
with the U.S. Armed Forces and reduced operating expenses. Total
revenue from government grants and development agreements was $3.8
million for the second quarter of 2004, compared to $2.0 million for
the second quarter of 2003.
    At June 30, 2004, the company had cash, cash equivalents and
short-term investments of $94.8 million.
    Loan principal and accrued interest under a credit facility with
Baxter Capital Corporation is classified as a current liability on the
balance sheet, due to a dispute concerning the timing of repayment.

    QUARTERLY CONFERENCE CALL

    The company has scheduled its quarterly conference call for 4:30
p.m. EDT today. Interested parties can access a live Internet
broadcast at http://www.cerus.com/pages/IR/wc.html. For those unable
to listen to the live broadcast, the call will be archived at
www.cerus.com.

    ABOUT CERUS

    Cerus Corporation is developing novel technologies to provide
safer and more effective options to patients in areas with substantial
unmet medical needs. The Concord, California-based company is pursuing
novel therapeutic vaccine technologies to harness the power of the
immune system against cancer and infectious disease. In collaboration
with MedImmune, Inc., Cerus is developing a therapeutic vaccine
designed to target antigens expressed in breast, prostate and colon
cancer, as well as metastatic melanoma. Cerus is also collaborating
with subsidiaries of Baxter International Inc. on the INTERCEPT Blood
System, designed to enhance the safety of the world's blood supply by
inactivating viruses, bacteria, other pathogens and white blood cells.
The INTERCEPT Blood System is based on the company's Helinx technology
for controlling biological replication. The INTERCEPT Blood System for
platelets is currently being marketed in Europe.

    Helinx is a trademark of Cerus Corporation.
    Baxter and INTERCEPT Blood are trademarks of Baxter International
Inc.

    Statements in this news release regarding potential efficacy of
products, product development and commercial potential, possible
outcomes of the loan dispute, and the company's relationship with
subsidiaries of Baxter International Inc. are forward-looking
statements that involve risks and uncertainties. Actual results could
differ materially from the above forward-looking statements as a
result of certain factors, including the risks and uncertainty of the
timing and results of clinical trials and other development
activities, actions by regulatory authorities at any stage of the
development process, additional financing activities, manufacturing,
market acceptance of any products, competitive conditions, long term
growth opportunity of Cerus, legal proceedings, actions by Baxter and
other factors discussed in the company's most recent filings with the
Securities and Exchange Commission.


                           CERUS CORPORATION
               SELECTED UNAUDITED FINANCIAL INFORMATION

Condensed Statements of Operations Three Months Ended Six Months Ended
(in thousands, except per share        June 30,           June 30,
information)                         2004     2003     2004     2003
                                   -------- -------- -------- --------

Revenue                             $3,766   $2,003   $7,413   $3,272

Operating expenses:
  Research and development           8,720   14,752   17,388   29,447
  General and administrative         2,919    2,823    5,962    5,518
  Restructuring                      2,465        -    2,465        -
                                   -------- -------- -------- --------
     Total operating expenses       14,104   17,575   25,815   34,965
                                   -------- -------- -------- --------
        Loss from operations       (10,338) (15,572) (18,402) (31,693)
Interest income (expense), net      (1,209)  (1,200)  (2,339)  (2,238)
                                   -------- -------- -------- --------
        Net loss                   (11,547) (16,772) (20,741) (33,931)
                                   ======== ======== ======== ========

Net loss per share - basic and
 diluted                            ($0.52)  ($0.97)  ($0.94)  ($2.04)
                                   ======== ======== ======== ========
Shares used in computing net loss
 per share - basic and diluted      22,113   17,317   22,099   16,644




Condensed Balance Sheets                        June 30,  December 31,
(in thousands)                                   2004        2003
                                               ----------  ----------

Cash, cash equivalents and short-term
 investments                                     $94,817    $110,010
Accounts receivable from a related party              59           8
Accounts receivable and other current assets       6,034       5,736
Furniture and equipment, net                       1,183       2,553
Other assets                                         117         156
                                               ----------  ----------

   Total assets                                 $102,210    $118,463
                                               ==========  ==========


Accounts payable to a related party               $2,500      $3,156
Current loan and interest payable to a related
 party                                            58,694      55,834
Other current liabilities                          9,033       6,945
Stockholders' equity                              31,983      52,528
                                               ----------  ----------

   Total liabilities and stockholders' equity   $102,210    $118,463
                                               ==========  ==========


    CONTACT: Cerus Corporation
             Greg W. Schafer, 925-288-6109