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                                                                   EXHIBIT 10.23

                              CONSULTING AGREEMENT

        THIS CONSULTING AGREEMENT, having an effective date of December 19,
2000, is made between NEORX CORPORATION (hereinafter referred to as "NeoRx"),
410 West Harrison, Seattle, Washington 98119, and CARL S. GOLDFISCHER, M.D.
(hereinafter referred to as "Consultant"),                                     .
                                          -------------------------------------

        The parties agree as follows:

        1. Term. The term of this Agreement shall be from December 19, 2000
through June 19, 2001 and is renewable for two additional six month periods.
Either party may terminate this Agreement immediately with cause, or upon 30
days prior written notice without cause.

        2. Services to be Provided. Consultant shall provide consulting services
primarily related to STRATEGIC AND FINANCIAL ISSUES. Such services will be
provided 2-3 days per week.

        3. Independent Contractor. The parties understand and hereby acknowledge
that nothing in this Agreement shall be construed to create any relationship
other than that of an independent contractor relationship for purposes of and
services rendered under this Agreement. The parties also acknowledge that
Consultant is currently a member of NeoRx's Board of Directors. Under this
Agreement, NeoRx will, however, retain no control over the methods by which
Consultant performs his services, provided, however, that the days on which
Consultant's services are required may be determined by NeoRx according to its
needs. These services may be provided to NeoRx by telephone or at meetings
convened at a mutually agreeable time and place, or may be provided to others at
NeoRx's request.

        4. Compensation. During the term of this Agreement, NeoRx shall pay
Consultant the sum of $10,000 once monthly, beginning in January 2001, upon
receipt of an invoice for the services directed to "Attention: Kenneth Chow."
Consultant understands that he is an independent contractor and will be
responsible for his own withholding taxes and social security deductions.

        As further compensation, NeoRx shall also grant Consultant certain stock
options.

        The invoice submitted by Consultant shall provide the date and a brief
description of services rendered per day, and NeoRx shall provide payment for
approved services within thirty (30) days of receipt of such invoice. In
addition, NeoRx shall reimburse Consultant for actual and necessary
out-of-pocket expenses incurred, where such expenses are related to services
rendered under this Agreement. Consultant shall submit a monthly itemized
expense statement to NeoRx and NeoRx shall provide reimbursement of approved
expenses within thirty (30) days of receipt of such statement; this expense
statement shall also be directed to the attention of Kenneth Chow.


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        5. Confidential Information and Property. Consultant agrees that he will
not disclose or use any Confidential Information relating to NeoRx, or any
property of NeoRx, except as NeoRx shall direct. "Confidential Information"
includes all plans, research, test procedures and results, products, formulas,
processes, protocols, computer data, customer lists, marketing plans, financial
information, business strategies, relationships with third parties of NeoRx, and
all information related to NeoRx and not generally available to the public.
"Property" means chemical, biochemical, biological, synthetic and other
materials used in NeoRx's business. Consultant agrees that no patent rights or
licenses are granted to Consultant by this paragraph, and further agrees that
NeoRx has no obligation to grant Consultant any rights in patents, Confidential
Information or property of NeoRx. Consultant consents that NeoRx may disclose to
others that he is acting as a consultant relative to the services described in
paragraph 2. The restrictions contained in this paragraph 5 concerning
confidentiality shall be effective during the term of this Agreement and at all
times thereafter.

        6. Exceptions. Consultant shall not be subject to the restrictive
obligations set forth in Section 5 as to the disclosure or use of any
information which : (1) is or later becomes publicly known under circumstances
involving no breach of this Agreement by Consultant; (2) is already known to
Consultant at the time of receipt of the information; (3) is lawfully made
available to Consultant by a third party; or (4) is required by law or
regulation.

        Specific Confidential Information shall not be considered to fall within
the above exceptions merely because it is within the scope of more general
information within an exception. Furthermore, a combination of features shall
not be considered to fall within the above exceptions unless the combination
itself, including its principles of operation, are within the exceptions.

        7. Assignment. All Inventions which Consultant conceives, develops or
actually reduces to practice, either alone or with others, relating to the
actual services provided by Consultant shall be the exclusive property of NeoRx.
Consultant hereby assigns to NeoRx or its designee all of Consultant's right,
title and interest in and to any Invention, any patent applications relating
thereto, and any patents granted thereon, and will execute any such formal
Assignment documents upon request of NeoRx. Consultant shall disclose such
Inventions to NeoRx promptly and in writing. When requested and at NeoRx's
expense, Consultant will assist NeoRx or its designee in efforts to protect
NeoRx's proprietary and patent rights to such Inventions.

        For the purposes of this Agreement, "Invention" shall mean all
inventions, discoveries, concepts and ideas, whether patentable or not,
including but not limited to articles, processes, methods, formulas, systems and
techniques, as well as improvements and derivations and know-how related
thereto.

        8. Adherence to Terms. Consultant agrees that he shall require his
officers, employees, affiliates, associates, agents, contractors and other
personnel to adhere to the terms of this Agreement.

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        9. Entire Agreement. This Agreement expresses the entire understanding
between the parties on the subject matter hereof. The provisions of this
Agreement may not be waived or modified except by a writing signed by the party
against whom enforcement is sought. No waiver of breach shall constitute a
subsequent waiver of any subsequent breach, and if any provisions of this
Agreement are held to be invalid or unenforceable, the remaining provisions
shall remain valid and enforceable.

                                     NeoRx Corporation

                                     By:
                                         ---------------------------------------
                                            Paul G. Abrams, M.D., J.D.
                                            Chief Executive Officer


                                     By:
                                         ---------------------------------------
                                            Carl S. Goldfischer, M.D.

                                     Soc. Sec. or Tax ID:
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