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                                                                    EXHIBIT 10.4


                           LOAN MODIFICATION AGREEMENT

         This Loan Modification Agreement is entered into as of March 21, 2001
by and between Maxim Pharmaceuticals, Inc. (the "Borrower") and Silicon Valley
Bank ("Bank").

1.       DESCRIPTION OF EXISTING INDEBTEDNESS: Among other indebtedness which
may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to,
among other documents, a Loan and Security Agreement, dated on or about October
9, 2000, as may be amended from time to time (the "Loan Agreement"). The Loan
Agreement provided for, among other things, a Committed Term Line in the
original principal amount of Four Million Dollars ($4,000,000). Defined terms
used but not otherwise defined herein shall have the same meanings as in the
Loan Agreement.

Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as
the "Indebtedness."

2.       DESCRIPTION OF COLLATERAL AND GUARANTIES. Repayment of the Indebtedness
is secured by the Collateral as described in the Loan Agreement.

Hereinafter, the above-described security documents and guaranties, together
with all other documents securing repayment of the Indebtedness shall be
referred to as the "Security Documents". Hereinafter, the Security Documents,
together with all other documents evidencing or securing the Indebtedness shall
be referred to as the "Existing Loan Documents".

3.       DESCRIPTION OF CHANGE IN TERMS.

         A.       MODIFICATION(S) TO LOAN AGREEMENT.

                  1.       The following term as defined in Section 1.1 entitled
                           "Definitions" is hereby amended to read as follows:

                           "Committed Term Line" means a credit extension of up
                           to Three Million Two Hundred Thousand Dollars
                           ($3,200,000).

                  2.       The term "Term Availability End Date" as defined in
                           paragraph "(a)" under Section 2.1.2 entitled "Term
                           Loans: Etc." is hereby amended to mean September 30,
                           2001.

                  3.       Notwithstanding the terms and conditions contained in
                           paragraph "(a)" under Section 2.1.2 entitled "Term
                           Loans: Etc.", (i) the first Term Loan is not required
                           to be made substantially concurrently with the
                           execution of the Loan Agreement; (ii) Term Loans may
                           be used to finance Equipment purchased on or after
                           October 1, 2000; and (iii) the original principal
                           amount of Term Loans relating to leasehold
                           improvements and/or software licenses shall not
                           exceed $1,200,000.

                  4.       Paragraph "(d)" under Section 2.1.2 entitled "Term
                           Loans: Etc." is hereby amended in part to provide
                           that Term Loan payments shall begin on November 1,
                           2001 and a final payment will be due no later than
                           April 1, 2005.

                  5.       Notwithstanding the terms and conditions contained in
                           paragraph "(f)" under Section 2.1.2 entitled "Term
                           Loans, Etc.", the repayment fees are amended as
                           follows:

                           From October 1, 2001 through September 30, 2002: 3%;
                           From October 1, 2002 through September 30, 2003: 2%;
                           From October 1, 2003 through September 30, 2004: 1%;
                           From October 1, 2004 through April 1, 2005: 0%.


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                  6.       The minimum aggregate balance required, as described
                           in Section 6.7 entitled "Principal Depository", is
                           hereby decreased from $5,000,000 to $4,000,000.

                  7.       Section 6.9 entitled "Financial Covenant" is hereby
                           amended to read as follows:

                           Borrower will maintain at all times a Remaining
                           Months Liquidity of at least 9 months, to be tested
                           quarterly.

                           "Remaining Months Liquidity" is defined as Liquidity
                           divided by Cash Burn.

                           "Liquidity" is defined as: Unrestricted cash and
                           equivalents.

                           "Cash Burn" is defined as: Net after-tax income
                           (loss) plus amortization and depreciation.

                           Borrower shall maintain a certificate of deposit to
                           be held on account with Bank in a minimum principal
                           amount equivalent to 100% of the aggregate
                           outstanding Obligations at such time as Borrower
                           fails to meet this Remaining Months Liquidity
                           covenant and until such time as Borrower restores and
                           maintains compliance with the terms of this
                           Agreement. Provided Borrower maintains such
                           certificate of deposit held on account with Bank, it
                           shall not be deemed an Event of Default if Borrower
                           does not comply with this Remaining Months Liquidity
                           covenant.

         B.       WAIVER OF DEFAULT.

                  1.       Bank hereby waives Borrower's existing default under
                           the Loan Agreement by virtue of Borrower's failure to
                           comply with Section 8.11 entitled "Recall of
                           Governmental Disapproval of Borrower's Products" as a
                           result of the Food and Drug Administration not
                           approving Borrower's Ceplene product in January,
                           2001. Bank's waiver of Borrower's compliance of this
                           covenant shall apply only to such specific instance.
                           Accordingly, for the term of the Loan Agreement,
                           Borrower shall be in compliance with this covenant.

                           Bank's agreement to waive the above-described default
                           (1) in no way shall be deemed an agreement by the
                           Bank to waive Borrower's compliance with the
                           above-described term as of all other dates and (2)
                           shall not limit or impair the Bank's right to demand
                           strict performance of this term as of all other dates
                           and (3) shall not limit or impair the Bank's right to
                           demand strict performance of all other terms or
                           covenants as of any date.

4.       CONSISTENT CHANGES. The Existing Loan Documents are hereby amended
wherever necessary to reflect the changes described above.

5.       PAYMENT OF LOAN FEE. Borrower shall pay Bank a fee in the amount of Two
Thousand Five Hundred Dollars ($2,500)(the "Loan Fee"), plus all out-of-pocket
expenses.

6.       NO DEFENSES OF BORROWER. Borrower (and each guarantor and pledgor
signing below) agrees that, as of the date hereof, it has no defenses against
the obligations to pay any amounts under the Indebtedness.

7.       CONTINUING VALIDITY. Borrower (and each guarantor and pledgor signing
below) understands and agrees that in modifying the existing Indebtedness, Bank
is relying upon Borrower's representations,


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warranties, and agreements, as set forth in the Existing Loan Documents. Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect.
Bank's agreement to modifications to the existing Indebtedness pursuant to this
Loan Modification Agreement in no way shall obligate Bank to make any future
modifications to the Indebtedness. Nothing in this Loan Modification Agreement
shall constitute a satisfaction of the Indebtedness. It is the intention of Bank
and Borrower to retain as liable parties all makers and endorsers of Existing
Loan Documents, unless the party is expressly released by Bank in writing. No
maker, endorser, or guarantor will be released by virtue of this Loan
Modification Agreement. The terms of this paragraph apply not only to this Loan
Modification Agreement, but also to all subsequent loan modification agreements.

8.       CONDITIONS. The effectiveness of this Loan Modification Agreement is
conditioned upon payment of the Loan Fee.

         This Loan Modification Agreement is executed as of the date first
written above.


BORROWER:                                  BANK:

MAXIM PHARMACEUTICALS, INC.                SILICON VALLEY BANK



By: /s/ Dale A. Sander                     By: /s/ Linda S. Le Beau

Name: Dale A. Sander                       Name: Linda S. Le Beau

Title: Chief Financial Officer             Title: Senior Vice President