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                                                                    EXHIBIT 8.01



                                ___________, 1999



Corixa Corporation
1124 Columbia Street
Seattle, Washington 98104

Ladies and Gentlemen:

         We have acted as counsel for Corixa Corporation, a Delaware corporation
("Corixa"), in connection with the preparation and execution of the Agreement
and Plan of Reorganization dated as of December 11, 1998, by and among Corixa,
Yakima Acquisition Corporation, a Delaware corporation and a wholly-owned
subsidiary of Corixa ("Merger Sub"), and Anergen, Inc., a Delaware corporation
("Anergen"). Pursuant to the Agreement, Merger Sub will merge with and into
Anergen (the "Merger"), and Anergen will become a wholly-owned subsidiary of
Corixa. Unless otherwise defined, capitalized terms referred to herein have the
meanings set forth in the Agreement. All section references, unless otherwise
indicated, are to the Internal Revenue Code of 1986, as amended (the "Code").

         You have requested our opinion regarding certain United States federal
income tax consequences of the Merger. In delivering this opinion, we have
reviewed and relied upon (without any independent investigation) the facts,
statements, descriptions and representations set forth in the Agreement
(including Exhibits) and such other documents pertaining to the Merger as we
have deemed necessary or appropriate. We have also relied upon (without any
independent investigation) certificates of officers of Corixa, Merger Sub and
Anergen, respectively (the "Officers' Certificates").

         In connection with rendering this opinion, we have also assumed
(without any independent investigation) that:

         1. Original documents (including signatures) are authentic, documents
submitted to us as copies conform to the original documents, and there has been
(or will be by the Effective Time) due execution and delivery of all documents
where due execution and delivery are prerequisites to effectiveness thereof;

         2. Any representation or statement referred to above made "to the
knowledge of," "to the best of the knowledge" or otherwise similarly qualified
is correct without such qualification. As to all matters in which a person or
entity making a representation referred to above has represented that such
person or entity either is not a party to, does not have, or is not aware 


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Corixa Corporation
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of, any plan, intention, understanding or agreement, there is in fact no such
plan, intention, understanding or agreement;

         3. All statements, descriptions and representations contained in any of
the documents referred to herein or otherwise made to us are true and correct in
all material respects and will continue to be true and correct in all material
respects as of the Effective Time and all other relevant times, and no actions
have been (or will be) taken which are inconsistent with such representations;

         4. The Merger will be reported by Corixa and Anergen on their
respective federal income tax returns in a manner consistent with the opinion
set forth below;

         5. The Merger will be consummated in accordance with the Agreement (and
without any waiver, breach or amendment of any of the provisions thereof) and
will be effective under the applicable state laws; and

         6. The opinion of Wilson Sonsini Goodrich & Rosati, Professional
Corporation, regarding certain United States federal income tax consequences of
the Merger has been issued and not withdrawn.

         Based on our examination of the foregoing items and subject to the
assumptions, exceptions, limitations and qualifications set forth herein, we are
of the opinion that, if the Merger is consummated in accordance with the
Agreement (and without any waiver, breach or amendment of any of the provisions
thereof) and the statements set forth in the Officers' Certificates are true and
correct as of the Effective Time, then for federal income tax purposes the
Merger will constitute a "reorganization" as defined in Section 368(a) of the
Code.

         This opinion represents and is based upon our best judgment regarding
the application of federal income tax laws arising under the Code, existing
judicial decisions, administrative regulations and published rulings and
procedures. Our opinion is not binding upon the Internal Revenue Service or the
courts, and there is no assurance that the Internal Revenue Service will not
successfully assert a contrary position. Furthermore, no assurance can be given
that future legislative, judicial or administrative changes, on either a
prospective or retroactive basis, would not adversely affect the accuracy of the
conclusions stated herein. Nevertheless, we undertake no responsibility to
advise you of any new developments in the application or interpretation of the
federal income tax laws.

         This opinion addresses only the classification of the Merger as a
reorganization under Section 368(a) of the Code, and does not address any other
federal, state, local or foreign tax 



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Corixa Corporation
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consequences that may result from the Merger or any other transaction (including
any transaction undertaken in connection with the Merger).

         No opinion is expressed as to any transaction other than the Merger as
described in the Agreement or to any transaction whatsoever, including the
Merger, if all the transactions described in the Agreement are not consummated
in accordance with the terms of such Agreement and without waiver or breach of
any material provision thereof or if all of the representations, warranties,
statements and assumptions upon which we relied are not true and accurate at all
relevant times. In the event any one of the statements, representations,
warranties or assumptions upon which we have relied to issue this opinion is
incorrect, our opinion might be adversely affected and may not be relied upon.

         This opinion has been delivered to you for the purpose of satisfying
the requirements of Section 6.1(f) of the Agreement. It may not be relied upon
for any other purpose or by any other person or entity, and may not be made
available to any other person or entity without our prior written consent. We
hereby consent to the filing of this opinion as an exhibit to the Registration
Statement and to the use of our name under the heading "Material Federal Income
Tax Consequences" therein. In giving such consent, we do not thereby admit that
we are in the category of persons whose consent is required under Section 7 of
the Securities Act of 1933, as amended.


                                              Very truly yours,

                                              VENTURE LAW GROUP
                                              A Professional Corporation



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