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                                           Filed by Corixa Corporation
                                           Pursuant to Rule 425 Under the
                                           Securities Act of 1933 and Deemed
                                           Filed Pursuant to Rule 14a-12 Under
                                           the Securities Exchange Act of
                                           1934.  Subject Company: Coulter
                                           Pharmaceutical Inc. (Commission
                                           File No. 0-21905)

For more information:

                                                   
Jim DeNike                                            Jen Reinhard
Corixa Corporation                                    FitzGerald Communications
206.754.5716                                          415.986.9500
denike@corixa.com                                     jreinhard@fitzgerald.com




FOR IMMEDIATE RELEASE

                  HART-SCOTT RODINO WAITING PERIOD EXPIRES FOR
                       PROPOSED CORIXA AND COULTER MERGER

SEATTLE, DEC. 12, 2000 -- Corixa Corporation (Nasdaq: CRXA), a research- and
development-based biotechnology company, today announced that the 30-day waiting
period required under the Hart Scott Rodino Antitrust Improvements Act of 1976,
as amended, for the merger of Corixa and Coulter to proceed has expired.
Stockholder meetings for both companies are scheduled for December 21, 2000.
Assuming stockholder approval, the transaction should be completed no later than
December 22, 2000.

ALL STOCKHOLDERS ARE URGED TO VOTE

As stated in the proxy statements mailed on November 21, 2000, all votes are
important regardless of the numbers of shares owned. Unless voted in person at
the Corixa stockholders meeting, proxy cards that are not returned by Corixa
stockholders will not be counted for the purpose of determining whether a quorum
is present at the Corixa stockholders meeting. Unless voted in person at the
Coulter stockholders meeting, proxy cards that are not returned by Coulter
stockholders will result in a vote "against" the approval of the merger.

ABOUT CORIXA

Corixa is a research-and-development-based biotechnology company committed to
treating and preventing autoimmune diseases, cancer and infectious diseases by
understanding and directing the immune system. Corixa is focused on
immunotherapeutic products and has a broad technology platform enabling both
fully integrated vaccine design and the use of its separate, proprietary vaccine
components on a standalone basis. The company partners with numerous developers
and marketers of pharmaceuticals and diagnostics, targeting products that are
Powered by Corixa(TM) technology with the goal of making its potential products
available to patients around the world. Corixa was founded in 1994 and is
headquartered in Seattle, Wash., with additional operations in Hamilton, Mont.
and Redwood City, Calif. For more information, please visit Corixa's website at
www.corixa.com or call the company's investor relations information line at
1-877-4CORIXA or 1.877.426.7492.

FORWARD-LOOKING STATEMENTS

Except for the historical information presented, certain matters discussed in
this press release are forward-looking statements. Forward-looking statements
are based on the opinions and estimates of management at the time the statements
are made. They are subject to certain risks and uncertainties



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that could cause actual results to differ materially from any future results,
performance or achievements expressed or implied by such statements. Factors
that could affect Corixa's actual results include, but are not limited to the
"Factors Affecting Our Operating Results, Our Business and Our Stock Price,"
described in our Quarterly Report on Form 10-Q/A filed on November 7, 2000 and
our Registration Statement on Form S-4/A filed on Nov. 17, 2000, copies of which
are available on our Web site, www.corixa.com. Readers are cautioned not to
place undue reliance on these forward-looking statements, which speak only as of
the date of this release.

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                   Additional Information and Where to Find It

On November 7, 2000 Corixa filed a Registration Statement on SEC Form S-4 in
connection with the merger, on November 17, 2000 Corixa filed an amendment to
the Registration Statement on SEC Form S-4 that was filed on November 7, 2000,
and on November 21, 2000 Corixa and Coulter mailed a Joint Proxy
Statement/Prospectus to stockholders of Corixa and Coulter containing
information about the merger. Investors and security holders are urged to read
the Registration Statement and the Joint Proxy Statement/Prospectus carefully.
The Registration Statement and the Joint Proxy Statement/Prospectus contain
important information about Corixa, Coulter and the merger and related matters.
Investors and security holders can obtain free copies of these documents through
the website maintained by the U.S. Securities and Exchange Commission at
http://www.sec.gov. Free copies of the Joint Proxy Statement/Prospectus and
these other documents may also be obtained:

- -- from Corixa by completing the material request form located in the "request
materials" section of Corixa's website at
http://www.corixa.com/financials/index.htm or by mail to Corixa, 1124 Columbia
Street, Suite 200, Seattle, Washington 98104-2040, attention: Investor
Relations, telephone: (206) 754-5711; or

- -- from Coulter by directing a request through the Investors Relations portion
of Coulter's website at http//www.coulterpharm.com or by mail to Coulter, 600
Gateway Boulevard, South San Francisco, California 94080, attention: Investor
Relations, telephone: (650) 553-1190.

In addition to the Registration Statement and the Joint Proxy
Statement/Prospectus, Corixa and Coulter file annual, quarterly and special
reports, proxy statements and other information with the Securities and Exchange
Commission. You may read and copy any reports, statements or other information
filed by Corixa or Coulter at the SEC public reference rooms at 450 Fifth
Street, N.W., Washington, D.C. 20549 or at any of the Commission's other public
reference rooms in New York, New York and Chicago, Illinois. Please call the
Commission at 1-800-SEC-0330 for further information on the public reference
rooms. Corixa's and Coulter's filings with the Commission are also available to
the public from commercial document-retrieval services and at the website
maintained by the Commission at http://www.sec.gov.

Interests of Certain Persons in the Merger

Coulter will be, and certain of Coulter's directors and executive officers may
be, soliciting proxies from Coulter stockholders in favor of the adoption of the
merger agreement. In addition, Corixa will be, and certain of Corixa's directors
and executive officers may be, soliciting proxies from Corixa stockholders in
favor of the adoption of the merger agreement. The directors and executive
officers of Coulter and the directors and executive officers of Corixa may be
deemed to be participants in Coulter's and Corixa's solicitation of proxies.

The directors and executive officers of Coulter have interests in the merger,
some of which may differ from, or may be in addition to, those of Coulter's
stockholders generally. For a description of such interests and a list of each
company's directors and executive officers, please see the press release filed
with the SEC pursuant to Rule 425 by Corixa and Coulter on October 16, 2000.



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