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                                  EXHIBIT 10.28

                             SECURED PROMISSORY NOTE

PRINCIPAL AMOUNT:  $110,000.00                             DATE:  April 7, 1999

                                                           SAN DIEGO, CA



1.   PROMISE TO PAY. LARRY G. STAMBAUGH, ("Borrower") at 17947 Corazon Place,
     San Diego, CA 92127, hereby promises to pay, in lawful money of the United
     States of America, to the order of MAXIM PHARMACEUTICALS, INC., ("Lender")
     a Delaware Corporation, at 8899 University Center Lane, Suite 400, San
     Diego, CA 92122, the principal amount of One Hundred and Ten Thousand
     ($110,000) dollars together with interest thereon from the date hereof at
     the rate of 7 percent (7%) percent per annum.

2.   PAYMENT. Borrower will pay outstanding principal plus all accrued unpaid
     interest by April 7, 2000. Borrower will pay Lender at Lender's address
     shown above or at such other place as Lender may designate in writing.
     Unless otherwise agreed or required by applicable law, payments will be
     applied first to accrued unpaid interest, then to any unpaid collection
     costs and late charges, and any remaining amount to principal.

3.   SECURITY. To secure the payment on the obligations under this Note,
     Borrower hereby grants to Lender a security interest in all options to
     purchase, or any shares acquired thereunder, common stock of Maxim
     Pharmaceuticals, Inc. granted to Borrower, as more fully set forth in the
     Exhibit A hereto (the "Options"). Notwithstanding the granting by the
     Borrower of the security interest as provided herein (a) Borrower
     acknowledges his obligation to repay the Secured Promissory Note in
     accordance with its terms and provisions, and (b) Lender shall have full
     recourse against Borrower for all amounts due under this Secured Promissory
     Note. The Borrower may elect to sell common stock underlying the Options if
     the value of the remaining Options equals or exceeds the obligations under
     this.


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4.   PREPAYMENT. Borrower may pay all or a portion of the amount owed earlier
     than it is due at any time without notice and without penalty.

5.   DEFAULT. Borrower will be in default (a) five (5) days after written notice
     of failure by Borrower to make any payment in connection with this loan
     within ten (10) days after due; or (b) immediately when a receiver is
     appointed for any part of Borrower's property, Borrower makes an assignment
     for the benefit of creditors, or any proceeding is commenced either by
     Borrower or (unless dismissed within 60 days) against Borrower under any
     bankruptcy or insolvency laws.

6.   LENDER'S RIGHTS. Upon default, Lender may declare the entire unpaid
     principal balance on this Note and all accrued interest immediately due. In
     such event, subject to any limits under applicable law, Borrower shall also
     pay Lender's reasonable attorney's fees and legal expenses whether or not
     there is a lawsuit, including attorney's fees and legal expenses for
     bankruptcy proceedings (including efforts to modify or vacate any automatic
     stay or injunction), appeals, and any anticipated post-judgment collection
     services. Borrower also will pay any court costs, in addition to all other
     sums provided by law. This Note has been delivered to Lender and accepted
     by lender in the State of California. If there is a lawsuit, Borrower
     agrees upon Lender's request to submit to the jurisdiction of the courts of
     San Diego County, the State of California. This Note shall be governed by
     and construed in accordance with the laws of the State of California.

7.   GENERAL PROVISIONS. Lender may delay or forgo enforcing any of its rights
     or remedies under this Note without losing them. Borrower and any other
     person who signs, guarantees or endorses this Note, to the extent allowed
     by law, waive any applicable statute of limitations, presentment, demand
     for payment, protest and notice of dishonor.

8.   NOTICES. All notices required to be given hereunder shall be given in
     writing and shall be effective when actually delivered or three days after
     deposited in the mail, first class, postage prepaid, addressed to the party
     to whom the notice is to be given at the address shown above.


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IN WITNESS WHEREOF, the Undersigned has caused this Secured Promissory Note to
be duly executed as of the day and year first above written.


BORROWER:

  /S/ LARRY G. STAMBAUGH
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LARRY G. STAMBAUGH