Document:

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                                                                  EXHIBIT  10.51

                                 PROMISSORY NOTE

                                DECEMBER 31, 2003
                                     (DATE)

               1124 COLUMBIA STREET, SUITE 200, SEATTLE, WA 98104
                               (ADDRESS OF MAKER)

FOR VALUE RECEIVED, CORIXA CORPORATION ("MAKER") promises, jointly and severally
if more than one, to pay to the order of GENERAL ELECTRIC CAPITAL CORPORATION or
any subsequent holder hereof (each, a "PAYEE") at its office located at 401
MERRITT 7 SUITE 23, NORWALK, CT 06851-1177 or at such other place as Payee or
the holder hereof may designate, the principal sum of SEVEN MILLION-- 00/100
DOLLARS ($7,000,000.00), with interest on the unpaid principal balance, from the
date hereof through and including the dates of payment, at a fixed interest rate
of Two and Eighty-Six Hundredths percent (2.86%) per annum, to be paid in lawful
money of the United States, in Sixty (60) consecutive monthly installments of
principal and interest as follows:

            Periodic
          Installment                    Total Amount

         Fifty-Nine  (59)                $125,054.36

(each "Periodic Installment"), and a final installment which shall be in the
amount of the total outstanding principal and interest. The first Periodic
Installment shall be due and payable on January 1, 2004 and the following
Periodic Installments and the final installment shall be due and payable on the
same day of each succeeding month (each, a "Payment Date"). Such installments
have been calculated on the basis of a 360 day year of twelve 30-day months.
Each payment may, at the option of the Payee, be calculated and applied on an
assumption that such payment would be made on its due date.

The acceptance by Payee of any payment which is less than payment in full of all
amounts due and owing at such time shall not constitute a waiver of Payee's
right to receive payment in full at such time or at any prior or subsequent
time.

The Maker hereby expressly authorizes the Payee to insert the date value is
actually given in the blank space on the face hereof and on all related
documents pertaining hereto.

This Note is secured by the Master Security Agreement dated February 25, 2002
("SECURITY AGREEMENT").

Time is of the essence hereof. If any installment or any other sum due under
this Note or any Security Agreement is not received within ten (10) days after
its due date, the Maker agrees to pay, in addition to the amount of each such
installment or other sum, a late payment charge of five percent (5%) of the
amount of said installment or other sum, but not exceeding any lawful maximum.
If (i) Maker fails to make payment of any amount due hereunder within ten (10)
days after the same becomes due and payable; or (ii) Maker is in default under,
or fails to perform under any term or condition contained in any Security
Agreement, then the entire principal sum remaining unpaid, together with all
accrued interest thereon and any other sum payable under this Note or any
Security Agreement, at the election of

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Payee, shall immediately become due and payable, with interest thereon at the
lesser of eighteen percent (18%) per annum or the highest rate not prohibited by
applicable law from the date of such accelerated maturity until paid (both
before and after any judgment).

Notwithstanding anything to the contrary contained herein or in the Security
Agreement, Maker may not prepay in full or in part any indebtedness hereunder
without the express written consent of Payee in its sole discretion.

It is the intention of the parties hereto to comply with the applicable usury
laws; accordingly, it is agreed that, notwithstanding any provision to the
contrary in this Note or any Security Agreement, in no event shall this Note or
any Security Agreement require the payment or permit the collection of interest
in excess of the maximum amount permitted by applicable law. If any such excess
interest is contracted for, charged or received under this Note or any Security
Agreement, or if all of the principal balance shall be prepaid, so that under
any of such circumstances the amount of interest contracted for, charged or
received under this Note or any Security Agreement on the principal balance
shall exceed the maximum amount of interest permitted by applicable law, then in
such event (a) the provisions of this paragraph shall govern and control, (b)
neither Maker nor any other person or entity now or hereafter liable for the
payment hereof shall be obligated to pay the amount of such interest to the
extent that it is in excess of the maximum amount of interest permitted by
applicable law, (c) any such excess which may have been collected shall be
either applied as a credit against the then unpaid principal balance or refunded
to Maker, at the option of the Payee, and (d) the effective rate of interest
shall be automatically reduced to the maximum lawful contract rate allowed under
applicable law as now or hereafter construed by the courts having jurisdiction
thereof. It is further agreed that without limitation of the foregoing, all
calculations of the rate of interest contracted for, charged or received under
this Note or any Security Agreement which are made for the purpose of
determining whether such rate exceeds the maximum lawful contract rate, shall be
made, to the extent permitted by applicable law, by amortizing, prorating,
allocating and spreading in equal parts during the period of the full stated
term of the indebtedness evidenced hereby, all interest at any time contracted
for, charged or received from Maker or otherwise by Payee in connection with
such indebtedness; provided, however, that if any applicable state law is
amended or the law of the United States of America preempts any applicable state
law, so that it becomes lawful for the Payee to receive a greater interest per
annum rate than is presently allowed, the Maker agrees that, on the effective
date of such amendment or preemption, as the case may be, the lawful maximum
hereunder shall be increased to the maximum interest per annum rate allowed by
the amended state law or the law of the United States of America.

The Maker and all sureties, endorsers, guarantors or any others (each such
person, other than the Maker, an "OBLIGOR") who may at any time become liable
for the payment hereof jointly and severally consent hereby to any and all
extensions of time, renewals, waivers or modifications of, and all substitutions
or releases of, security or of any party primarily or secondarily liable on this
Note or any Security Agreement or any term and provision of either, which may be
made, granted or consented to by Payee, and agree that suit may be brought and
maintained against any one or more of them, at the election of Payee without
joinder of any other as a party thereto, and that Payee shall not be required
first to foreclose, proceed against, or exhaust any security hereof in order to
enforce payment of this Note. The Maker and each Obligor hereby waives
presentment, demand for payment, notice of nonpayment, protest, notice of
protest, notice of dishonor, and all other notices in connection herewith, as
well as filing of suit (if permitted by law) and diligence in collecting this
Note or enforcing any of the security hereof, and agrees to pay (if permitted by
law) all expenses incurred in collection, including Payee's actual attorneys'
fees. Maker and each Obligor agrees that fees not in excess of twenty percent
(20%) of the amount then due shall be deemed reasonable.

THE MAKER HEREBY UNCONDITIONALLY WAIVES ITS RIGHTS TO A JURY TRIAL OF ANY CLAIM
OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF, DIRECTLY OR INDIRECTLY, THIS
NOTE, ANY OF THE RELATED DOCUMENTS, ANY DEALINGS BETWEEN MAKER AND PAYEE
RELATING TO THE SUBJECT MATTER OF THIS

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TRANSACTION OR ANY RELATED TRANSACTIONS, AND/OR THE RELATIONSHIP THAT IS BEING
ESTABLISHED BETWEEN MAKER AND PAYEE. THE SCOPE OF THIS WAIVER IS INTENDED TO BE
ALL ENCOMPASSING OF ANY AND ALL DISPUTES THAT MAY BE FILED IN ANY COURT
(INCLUDING, WITHOUT LIMITATION, CONTRACT CLAIMS, TORT CLAIMS, BREACH OF DUTY
CLAIMS, AND ALL OTHER COMMON LAW AND STATUTORY CLAIMS.) THIS WAIVER IS
IRREVOCABLE MEANING THAT IT MAY NOT BE MODIFIED EITHER ORALLY OR IN WRITING, AND
THE WAIVER SHALL APPLY TO ANY SUBSEQUENT AMENDMENTS, RENEWALS, SUPPLEMENTS OR
MODIFICATIONS TO THIS NOTE, ANY RELATED DOCUMENTS, OR TO ANY OTHER DOCUMENTS OR
AGREEMENTS RELATING TO THIS TRANSACTION OR ANY RELATED TRANSACTION. IN THE EVENT
OF LITIGATION, THIS NOTE MAY BE FILED AS A WRITTEN CONSENT TO A TRIAL BY THE
COURT.

This Note and any Security Agreement constitute the entire agreement of the
Maker and Payee with respect to the subject matter hereof and supercedes all
prior understandings, agreements and representations, express or implied.

No variation or modification of this Note, or any waiver of any of its
provisions or conditions, shall be valid unless in writing and signed by an
authorized representative of Maker and Payee. Any such waiver, consent,
modification or change shall be effective only in the specific instance and for
the specific purpose given.

Any provision in this Note or any Security Agreement which is in conflict with
any statute, law or applicable rule shall be deemed omitted, modified or altered
to conform thereto.

                                           CORIXA CORPORATION

/s/ Russ Hawkinson                         By:  /s/ Greg Cox
(Witness)                                  (Signature)

Russ Hawkinson                             Greg Cox
(Print name)                               Print name (and title, if applicable)

1124 Columbia Street, Seattle, WA          91-1654387
(Address)                                  -------------------------------------
                                           (Federal tax identification number)

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                           COLLATERAL SCHEDULE NO. 004

THIS COLLATERAL SCHEDULE NO. 004 is annexed to and made a part of that certain
Master Security Agreement dated as of February 25, 2002 between GENERAL ELECTRIC
CAPITAL CORPORATION, together with its successors and assigns, if any, as
Secured Party and CORIXA CORPORATION as Debtor and describes collateral in which
Debtor has granted Secured Party a security interest in connection with the
Indebtedness (as defined in the Master Security Agreement) including without
limitation that certain Promissory Note dated _____________________________ in
the original principal amount of $7,000,000.00

See the attached Exhibit A, which more fully describes the equipment on this
schedule. Financing for $7,000,000.00 tenant improvements at Corixa's new
facilities, 1900 Ninth Ave., Seattle, WA 98101, per the construction contract
between Corixa Corporation and B.N. Builders, as attached.

Debtor authorizes Secured Party to file a financing statement and amendments
thereto describing the above-described Collateral and containing any other
information required by the applicable Uniform Commercial Code. Debtor
irrevocably grants to Secured Party the power to sign Debtor's name and
generally to act on behalf of Debtor to execute and file applications for title,
transfers of title, financing statements, notices of lien and other documents
pertaining to any or all of such Collateral; this power is coupled with Secured
Party's interest in the Collateral. Debtor ratifies its prior authorization for
Secured Party to file financing statements and amendments thereto describing the
Collateral and containing any other information required by the Uniform
Commercial Code if filed prior to the date hereof.

SECURED PARTY:                                  DEBTOR:

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GENERAL ELECTRIC CAPITAL CORPORATION            CORIXA CORPORATION

 By:                                            By:
     ----------------------------------             ----------------------------
 Title                                          Title:
       --------------------------------                -------------------------
 Date:                                          Date:
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                                                                   Exhibit 10.52

                        SECURITY DEPOSIT PLEDGE AGREEMENT
                                     (Loan)

     THIS SECURITY DEPOSIT PLEDGE AGREEMENT (this "AGREEMENT") is made and
entered into as of the 31st day of December, 2003, by and between CORIXA
CORPORATION a Delaware corporation with its principal place of business at 1124
Columbia Street, Suite 200, Seattle, WA 98104, ("DEBTOR") and GENERAL ELECTRIC
CAPITAL CORPORATION, a Delaware corporation, with its principal place of
business at 401 Merritt 7, Norwalk, CT 06851-1177 ("SECURED PARTY").

     In consideration of, and as an inducement for Secured Party to lend funds
to Debtor under the Master Security Agreement, dated as of February 25, 2002,
and Collateral Account Schedule No. 4139636-004 and Promissory Note related
thereto (the "MASTER SECURITY AGREEMENT AND COLLATERAL SCHEDULE AND PROMISSORY
NOTE THERETO BEING REFERRED TO AS THE "LOAN"), and to secure the payment and
performance of all of Debtor's obligations under the Loan, Debtor hereby
deposits and pledges with Secured Party the sum of THREE MILLION FIVE HUNDRED
THOUSAND AND 00/100 DOLLARS ($3,500,000.00) (the "COLLATERAL"), such pledge to
be upon the terms and conditions set forth below:

     1. Debtor delivers the Collateral to Secured Party to secure Debtor's
performance of its obligations under the Loan, including, but not limited to,
the timely payment of the Periodic Installments.

     2. The Collateral deposited with Secured Party shall not accrue interest.

     3. Upon any default by Debtor under the Loan, Secured Party may, at its
option, apply the Collateral towards the satisfaction of Debtor's obligations
under the Loan and the payment of all costs and expenses incurred by Secured
Party as a result of such default, including but not limited to, costs of
repossessing equipment and attorneys' fees. Such application shall not excuse
the performance at the time and in the manner prescribed of any obligation of
Debtor or cure a default of Debtor. Upon the application by Secured Party of any
amount of the Collateral pursuant to the terms of this paragraph, Debtor shall
be obligated to immediately pay to Secured Party an amount sufficient to cause
the Collateral to equal the amount first set forth above and in accordance with
Section 5 herein.

     4. Secured Party shall have no duty to first commence an action against or
seek recourse from Debtor, in the event of a default under the Loan, before
enforcing the provisions of, and proceedings under the provisions of this
Agreement. The obligations of Debtor under this Agreement shall be absolute and
unconditional and shall remain in full force and effect without regard to, and
shall not be released or discharged or in any way affected by:

     (a)  any amendment or modification of or supplement to the Loan;

     (b)  any exercise or non-exercise of any right, remedy or privilege under
          or in respect to this Agreement, the Loan, or any other instrument
          provided for in the Loan, or any waiver, consent, explanation,
          indulgence or actions or inaction with respect to any such instrument;
          or

     (c)  any bankruptcy, insolvency, reorganization, arrangement, readjustment,
          composition, liquidation or similar proceeding of Debtor.

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     5. So long as Debtor is not in default under the Loan or under any other
material financial obligation, Secured Party agrees to reduce the amount of the
Security Deposit to 50% of the outstanding principal balance on a semi-annual
calendar basis. Secured Party shall then refund to Debtor any Security Deposit
in excess of the reduced Security Deposit (less any portion of same cashed,
sold, assigned, or delivered pursuant to, and under the circumstances specified
in, Paragraph 3 hereof. The refunds will take place every six months commencing
July 1, 2006.

     6. Upon the termination of the Loan and the satisfaction of all of the
obligations of Debtor thereunder, Secured Party shall deliver to Debtor the
Collateral (less any portion of same cashed, sold, assigned or delivered
pursuant to and under the conditions specified in paragraph 3 hereof), and this
Agreement shall thereupon be without further effect.

     7. Secured Party may, without the consent of Debtor, assign this Agreement.
Debtor agrees that if Debtor receives written notice of an assignment from
Secured Party, Debtor will pay all amounts due hereunder to such assignee or as
instructed by Secured Party. Debtor also agrees to confirm in writing receipt of
the notice of assignment as may be reasonably requested by assignee. Debtor
hereby waives and agrees not to assert against any such assignee any defense,
set-off, recoupment claim or counterclaim which Debtor has or may at any time
have against Secured Party for any reason whatsoever.

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first above written.

SECURED PARTY:                                    DEBTOR:

GENERAL ELECTRIC CAPITAL CORPORATION              CORIXA CORPORATION

By: /s/ John Edel                                  By: /s/ Greg Cox

Name: John Edel                                    Name: Greg Cox

Title: Senior Vice President                       Title: Treasurer

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