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                                                                    EXHIBIT 4.01

     COMMON STOCK                                           COMMON STOCK
     CNVX NUMBER                                               SHARES
                                                         ___________________

INCORPORATED UNDER THE                                 SEE REVERSE FOR CERTAIN
   LAWS OF DELAWARE                                 DEFINITIONS AND RESTRICTIONS
                                     [LOGO]

                                                               CUSIP 13738Y 10 7

THIS CERTIFIES THAT:


IS THE HOLDER OF


             FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK,
                        $.00004 PAR VALUE PER SHARE, OF
    -------------------------CANCERVAX CORPORATION-------------------------

transferable on the books of the Corporation by the holder hereof in person or
by duly authorized attorney upon surrender of this Certificate properly
endorsed. This Certificate is not valid until countersigned by the Transfer
Agent and registered by the Registrar.

     WITNESS the facsimile seal of the Corporation and the facsimile signatures
of its duly authorized officers.

Dated:


/s/ HAZEL M. AKER                                 /s/ DAVID F. HALE
------------------------                          ------------------------
SENIOR VICE PRESIDENT AND    [CORPORATE SEAL]     PRESIDENT AND
SECRETARY                                         CHIEF EXECUTIVE OFFICER


COUNTERSIGNED AND REGISTERED
                    MELLON INVESTOR SERVICES LLC  TRANSFER AGENT
                                                  AND REGISTRAR


                                                  AUTHORIZED SIGNATURE


     Keep this certificate in a safe place. If it is lost, stolen, or destroyed
the Corporation will require a bond of indemnity as a condition to the issuance
of a replacement certificate.

     A statement of the powers, designations, preferences and relative,
participating, optional or other special rights of each class of stock or series
thereof and the qualifications, limitations or restrictions of such preferences
and/or rights as established, from time to time, by the Certificate of
Incorporation of the Corporation and by any certificate of determination, and
the number of shares constituting each class and series and the designations
thereof, may be obtained by the holder hereof upon written request and without
charge from the Secretary of the Corporation at the principal office of the
Corporation.

     The following abbreviations, when sued in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

 TEN COM-  as tenants in common
 TEN ENT-  as tenants by the entireties
  JT TEN-  as joint tenants with
           right of survivorship and
           not as tenants in common
COM PROP-  as community property

UNIF GIFT MIN ACT-_____________________ CUSTODIAN___________________________
                         (CUST)                           (MINOR)

                         under Uniform Gifts to Minors

                         Act________________________________________________
                                        (State)

UNIF TRF MIN ACT-_______ Custodian (until age ____)
                 (Cust)

                 _______ under Uniform Transfer to Minors Act ___________
                 (Minor)                                        (State)
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Additional abbreviations may also be used though not in the above list.

FOR VALUE RECEIVED, _____________________ hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFY NUMBER OF ASSIGNEE

______________________________________

________________________________________________________________________________
(PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________ Shares
of the common stock represented by the within Certificate, and do hereby
irrevocably constitute and appoint _____________________________________
Attorney to transfer the said stock on the books of the within named Corporation
with full power of substitution in the premises.


Dated: _________________      X ________________________________________________

                              X ________________________________________________
                                NOTICE: THE SIGNATURE(S) TO THE ASSIGNMENT MUST
                                CORRESPOND WITH THE NAME(S) AS WRITTEN UPON THE
                                FACE OF THE CERTIFICATE IN EVERY PARTICULAR,
                                WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE
                                WHATSOEVER.


Signature(s) Guaranteed:  By ___________________________________________________
                             THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN
                             ELIGIBLE GUARANTOR INSTITUTION (BANKS,
                             STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND
                             CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED
                             SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT
                             TO S.E.C. RULE 17Ad-15.

KEEP THIS CERTIFICATE IN A SAFE PLACE. IF IT IS LOST, STOLEN, MUTILATED OR
DESTROYED, THE CORPORATION WILL REQUIRE A BOND OF INDEMNITY AS A CONDITION TO
THE ISSUANCE OF A REPLACEMENT CERTIFICATE.


This certificate also evidences and entitles the holder hereof to certain rights
(the "Rights") as set forth in an Agreement between CancerVax Corporation (the
"Corporation") and Mellon Investor Services LLC, as Rights Agent, dated as of
November 3, 2004, as the same may be amended from time to time (the
"Agreement"), the terms of which are hereby incorporated herein by reference and
a copy of which is on file at the principal executive offices of the
Corporation. Under certain circumstances, as set forth in the Agreement, such
Rights will be evidenced by separate certificates and will no longer be
evidenced by this certificate. The Corporation will mail to the holder of this
certificate a copy of the Agreement without charge after receipt of a written
request therefor. AS DESCRIBED IN THE AGREEMENT, RIGHTS WHICH ARE OWNED BY,
TRANSFERRED TO OR HAVE BEEN OWNED BY ACQUIRING PERSONS OR ASSOCIATES OR
AFFILIATES THEREOF (AS DEFINED IN THE AGREEMENT) SHALL BECOME NULL AND VOID AND
WILL NO LONGER BE TRANSFERABLE.